DIY Home Solar ( as low as $1.26/Watt) - geni.us/project_solar Kil-A-Watt Meter - geni.us/ehGDWK EcoFlow Delta 2 - geni.us/u46bT EcoFlow Delta Pro - geni.us/smzZiC 100W Panels - geni.us/x7Tet Peak Solar Hours map - www.nrel.gov/gis/assets/images/solar-annual-ghi-2018-usa-scale-01.jpg DISCLAIMER: This video and description contain affiliate links, which means that if you click on one of the product links, I’ll receive a small commission.
Do not forget that once every day or so the modern fridges go into a "Defrost" mode. My GE, runs between 84 and 108 Watts, but at least 1 time a day it goes into a Defrost mode which can last up to 2 hours and stay at 315 Watts for those 2 hours. On my BrulTech Energy Management program it shows a rather large spike for that time frame. Normally the fridge mostly stays in the 80-90 range. On days where we were not home (vacation) the fridge averaged .8kW and on those days where the defrost kicked on it was 1.4kW. I have about 5 years of data by the minute.... lots of data
he ran a watthour monitor (which everyone should) for 24 hours.. I'd do 7 days though just to get a better idea. So it doesn't matter that it goes into defrost mode. You can buy many fridges without this mode and just deal with the ice build up. They are way more efficient, energy wise.
A couple of lessons learned from keeping the fridge running during and after a hurricane - 1. Room Temperature matters the hotter the room the longer the fridge will have to run to maintain temperature. 2. I found as the days without grid power increased the longer the fridge would run per cycle (longest cycle period was 6hrs) 3. The fridge may have additional features that can add to your power consumption (defrost cycle, heat strip around the freezer door) 4. Fill dead space with water bottles 👍 this is just good advice from an efficiency standpoint but extremely valuable when attempting to power your refrigerator without grid power. 5. Consider limiting wasted power by cycling the system on and off. And use a cooler for items people may grab between cycles - this is where the frozen water bottles really shine 👍🥶👍 Also I had to phone a friend on this one - My fridge was off for 4hrs and I plugged it in and the compressor didn’t start. I Checked the wattage and saw it was drawing over 300w but did not appear to be running. My friend said give it 15min it’s probably in a defrost cycle 🤦🏻♂️ I had been dealing with so many other catastrophes that I automatically assumed the worst 😂 15 minutes later the fridge started running just fine. If the cell phones were down I would have emptied my fridge into a cooler and planned on grilling the next day 🍗🍖🥩🍔…😂
Great advice, living in the Panhandle Of Florida hurricanes is a way of life for us. With the advance notice, I try to freeze some gallon milk jugs of water to use to help keep things cool in the refrigerator and freezer, plus you have some cool drinking water. Hurricane Michael was a monster and we were blessed just to have a house standing afterwards. Best regards!
As a former Floridian (1960's) hurricane season we had a mantra "bring in the dog and garbage cans, tape the windows, get new batteries for the radio, fill the bathtubs. As to #2 on your list, if the fridge duty cycles were longer off grid, that likely is due to your backup power system having less Amp/hour capacity than the grid.
I live on a solar independent offshore cruising sailboat with 400 watts of solar panels and 460 amphrs of battery storage. I have a refrigerator/ freezer I built out myself. The average retail refrigerator freezer is garbage. Consumers will not put up with 5”-6” of insulation and top loading, but that’s pretty much is what it takes to make an efficient refrigerator/freezer in the tropics. The boat is charged by 10:30am in the morning and can go for a week with no sun. Most of it comes down to proper frig. box construction and covering conductive, radiant, and convective heat flow properly.
If you don't care what it looks like then just glue 4 inch PIR insulation board to the outside of a normal chest fridge. Obviously don't cover any cooling fins or air vents. That'll get you close. You might be able to bend the pipes enough to move the fins away from the rear of the unit and get insulation on that face too. Just don't break any.
I agree on the chest style, cold is heavier than hot so when you open it it stays in there instead of falling to the floor and sucking in hot air that has to be cooled down again. I would love to see a video of this I have seen sailboat videos and the fridge freezer is under the seats or is by the sink in the galley.
For anyone interested you can control the defrost cycle on a fridge. Unfortunately, it is not part of the fridge settings. About 5 years ago a fellow RVer bought a Frigidaire residential fridge for his RV, but noticed that the defrost mode was killing his battery setup when it would kick in. Knowing that I was into electronics he asked for my assistance and I downloaded the fridge's wiring diagram and set him up with a manual switch/relay to deactivate the defroster when on battery power. Still works like a champ. I even sent him a diagram on how to automatically switch the defroster mode off when dry camping.
For frugal people who need only a tiny amount of fridge space, here is an alternative. We used to go on mid-summer vacations in Greece in our small two-person camping car. We used a tiny 18-litre (5 US gallons) Swiss-made fridge attached to the car battery. It uses the same efficient compression technology as a big fridge and is very well isolated. (The isolation probably takes in more than half of the total volume.) Moreover, it opens at the top, so the cold tends to stay inside even when the lid is open. We set this fridge to very cold while using the car, even though that meant our (Greek) yogurt might freeze. We rarely stayed longer than 2 days in one location, always lonely locations with no electric power source. We always took the fridge off the car's battery to avoid getting stranded. We did not add new food to the fridge while stationary, and never opened the lid for more than a few seconds. We obviously parked the car under trees, but even so it got very hot inside. The food in our fridge went from frozen to slightly above regular fridge temperature in these days. Occasionally we stayed up to 4 days in one place. This just required reconnecting the fridge once, on a less extreme setting, and letting it run for an hour off the full battery. All these measures were perfectly sufficient. We also used common sense in other ways, and so we never had food going off for lack of refrigeration.
@@raymondflavin8708 Sorry, that is not going to happen. Even if I did do videos for RUclips -- the fridge is now with my ex-wife. But if you want additional detail to make it more concrete: the fridge (I guess technically refrigerator box) was a Waeco CDF 18.
Refrigerators are much more efficient when they are fully loaded and have reached the desired temperature. The door of a fully loaded refrigerator can be briefly opened to access the contents without causing a measurable drop in the temperature of the thermal mass. There is less cold air volume in a fully loaded refrigerator (because the contents occupy most of the internal space). On the other hand, when the door is opened on empty refrigerator, the heavy cold air drops to the floor and the ambient warm (or hot) air takes its place and the refrigerator must energize the compressor to restore the desired temperature.
It's mostly that air doesn't have a lot of mass and food does. So a tiny mass escaping isn't a lot of energy. What you have said about the volumes is certainly true, but even if the volume didn't change when full, the amount of energy lost via the air is relatively small and quickly recovered by the heat pump.
You also have to consider the temperature of the room/location of where the refrigerator is located. People with "garage" refrigerators or freezers are using a lot of power to keep those doing their job. It's a two prong problem. First the insulation can only do so much in a hot environment. And secondly the compressor works less efficient because it uses the air in the location to transfer the heat from the coil in order to cool. The warmer the ambient air the harder the compressor has to work to keep the inside cold
You're correct! I also keep freezer packs in my off grid fridge. On very warm days I remove the freezer packs and place them around my food in the fridge to help maintain the cold.
Useful information! We have a 20 cubic feet bottom-freezer refrigerator in our off-grid house. As several people below, I disabled the defrost circuit, and manually defrost the freezer section twice a year. I recently bought an additional freezer from Costco - an 11 cubic feet upright model without a defrost feature. Adjusted to -13°C (8.6°F) it draws an all-day average of 32 Watts continuous power - drawing around 80 Watts, then cycling off. Simple "bang-bang logic".
Others in the comments have mentioned the thermal mass of the contents. For both freezers and refrigerators freeze gallon jugs of water and use them to fill up empty spots. The thermal mass will help regulate the inside temperature and in the event of a true power outage or multiple days without recharging keep the contents cold minimizing the on/off cycles.
Ice takes a lot of energy to change it's physical state back to liquid water again, so that's why it can be surprisingly effective under prolonged power outages. Although that's also why it also seems to take forever freezing it back the other way to ice.
Even better, I save the “single use” freeze packs often included in shipping frozen foods because they work over and over only the thin plastic bag they come in makes them single use. They freeze about 2-4 degrees lower than ice and have nearly identical energy requirements for phase transition on a volume basis meaning if you fill your extra freezer space with them they will actually melt first keeping your frozen items frozen.
@@hugegamer5988 I use large juice bottles filled with salt water. They work great for cold bags for groceries. Salt water freezes/thaws at 25F. Lots of thermal mass there.
I use gallon jugs filled with a 50/50 solution of RV antifreeze and water. Freezes/unfreezes around 10F, is nontoxic, and helps keep frozen things frozen.
I had NO idea that the conversion form DC to power standard AC appliance was such an energy hog; the fact the small inverter consumes as much power as the fridge it was feeding into is shocking. Excellent content BTW; thanks!
Look into inverters, not just power station inverters. The bigger the inverter the bigger the "dead" load (idle consumption for being on). In the case of mppt solar charger-inverters a 2000w one might consume 25w per hour, a 3000w 25-35w per hour, a 5000-6000w 45-55w and bigger ones like 10000w 70-80w. That adds up a LOT since 24 hours in a day times that you have to subtract from your batteries.. Solar does help offset that in light hours but not all day, and some even don't have solar when using a UPS setup . Cheers
A chest freezer/cooler is ALWAYS going to be more efficient due to the fact of opening the lid (cold air sinks!) You don't have the outrush of cold air like you would on the upright fridge/freezer, so less airspace turnover on the chest. Additionally, you have to consider "thermal mass" as a buffer. It's NOT efficient to keep a completely empty freezer or fridge. Augment the thermal mass of the chest freezer by adding in 2-liter bottles of frozen water to keep the temperature variance at a minimum...keeps the system from working so hard and can also tide you over for those sunless days!!!
Truth, the chest freezer in my RV draws 250-1000Wh per day depending on ambient temps (40-120F) the smaller dorm style fridge in the same conditions draws between 750-2000Wh per day I run it on 700W collection, 12V300Ah battery and 3000W inverter. The Panels sit flat on my RV and present an issue with snow in the winter, December seems to be the only month I have issues
We have a chest freezer from the 80's that was in the basement when we moved into our house. I've replaced the thermostat twice, but the compressor still sounds like it could run for another 40 years. Anyway, besides how well-built older chest freezers are, I wanted to mention that we have always had about a dozen four liter milk jugs filled with water and two pieces of half inch plywood on top of them to provide a much easier to reach "false bottom" and provide several days of security for the contents in the event of a power failure. Thermal mass can definitely prolong unpowered storage time.
@@glitchr8r Also could keep several frozen bottles on hand to take out and put in the refrigerator to keep it cool if necessary!!! Having those extra bottles of frozen clean water also provides something to drink when they thaw out!!! 👍🏻
@@davidconner-shover51 Hi, could you refine your comment on "dorm style fridge" to include cubic foot of the unit? I'm looking to buy a 10 cubic foot dorm style refrigerator for my RV. Size matters.
Fine tunes: 1. Where applicable, (portable, etc) A DC fridge will save you all the inversion loss and make it simple to connect a home brewed cheap battery pack for 1-2 days poor sun run time. 2. A capacitor in a box will solve start up draw on either system, so don't have to design to a power level you only cycle 6 times a day. Great presentation! If you did the above, I'd love to know how much smaller you could tweak your power supply array for a similar DC fridge!
For rainy days or if in Alaska where you only get a few hours of day light. I would just place the panels inside a shipping container- use super bright Cobb style l.e.d. Lights and use a ""Fernel lense" to boost the l.e.d. light into the solar panels. Yes, you will lose some of the power from batteries at night time but get more in daylight! Even using exr soar high output panels.
My experience has shown after building three systems, it’s best to have at least twice the amount of panels, batteries, and inverter just in case! Especially in the winter.
I would bet on three times. You also havevto account for capacitance of heat in the fridge. Fill it with water and it will stay colder than an empty fridge when you open it. To really save money set gallons of water outside to freeze in the winter then put them in the fridge.
I always compute what my max electrical power draw will be and then target 1.4 x number of panels at max power to equal that draw. The .4 addition accounts for the tracking of the sun.
@@simon359 This is why my panels are tilted more perpendicular during summer months.... I can afford to run "leaner" in the winter months since my AC isn't running full throttle.
My fridge freezer has been running on my Delta Pro, Powerstream inverter (the AC is never on, the PS inverter uses 16W), an EF smart plug and 1600W of solar for over a year now. For an entire year it used 339.78kWh and that’s using it normally, opening the fridge 10-20 times a day as a family fridge freezer keeping cool what’s in it, cooling what we put in it and regularly freezing pots of ice cream made in our Ninja Creami. I now have another couple of smart plugs linked to the system providing power to the main bedroom and lounge for an Apple Mac mini, 32” monitor, a 55” TV, a 32” TV, a couple of iPads and iPhones along with the router and other vampire power draw devices. I also have the inverter set to provide 30W of power to my home circuit. Only in the very depths of winter do I need to top it up at night with half price power from the grid, my power bills are essentially just the standing charge, the cost of top up and whatever we use in the kitchen for cooking. Well worth the investment imo, especially given the now proven longevity of Lifepo4 batteries.
I have an upright deep freezer and a fridge freezer combo, what I have found running them 24, 7 is that both together pull around 200 watts down to 100 watts when they both are idle, but when they are running it can go as high as 600 to 800 watts likely both defrosting at the same time, but a 24 volt 200 amp hour battery was not enough to take them through the night, I had to buy another battery so now I have 24 volt 400 amp hours of storage and 2000 watts of solar, so far its been able to keep them going day and night the battery bank gets down to around 60 percent overnight so more battery is recommended. This is being home and daily use doors get opened several times a day as well.
I performed a test powering my fridge for two hours, four times per 24 hour period. I also ran a test similar to the ones used here. The differences in results were dramatic. While the temp inside the fridge did vary two-three degrees more during the first test, it was well within a safe zone for refrigerated/frozen foods. Moral: You can vastly extend the time you can power a fridge by eliminating the inverter "idle" time.
nice, you could further design the fridge for the power source by replacing insulation with mass. If the walls are [say] 3 meters of mud it will run excessively for about 2 months and take as much time to heat up if the power is disconnected. As it doesn't really matter when the pump runs you don't really need a battery. Can just crank the compressor with wind or solar directly when it is available. Could even put the cooling inside the 3 meter wall of mud to get even more stable cooling.
I'm an engineer and I find all of this fascinating. I lived in southern California for decades and 40 years ago we even had parabolic solar water heater panels on our roof. Today we live on the Gulf Coast. We get plenty of sunshine, but have hurricanes that require some form of alternative electrical generation. I installed a 24kW Generac natural gas generator and an automatic transfer switch. I choose to leave solar gathering to the utility companies for economies of scale. While it's fascinating, without wasteful government intervention the DIY power generation concept doesn't make economic sense. In my humble opinion of course.
You live in an area that must be ready for hurricanes, and an alternative power source such as $9,000 of generator+installation is a must as long as it can accept propane tanks in a dual fuel arrangement. We have a mid 1980's gasoline generator that has only been used once: by a coworker about 15 years ago in the mountain fires recovery area. However, there is another factor, and it concerns the condition of the grid in each family's vicinity. The grid is teetering in areas, causes forest fires in others, and is the main problem with economies of scale, especially after a disaster. Look at Japan and the nuclear plant disaster. Six months later, plenty of families in the region still had no electricity. We have sun and a decaying grid in California, with fire danger, because the so-called public utilities companies have been investor-owned for 30 years. They refuse to invest in the grid. So, DIY can prevent long-term power disruption in a household.
You did aq great job presneting the information. This video is very relative to our situation. We went through a similar method when we sized our solution. We used a battery monitor system like the Victron BMV-712 to understand the power needs of our system in real world situations prior to upgrading batteries or adding solar. We have a class A RV with a residential refrigerator. The original lead acid house batteries were challenged by the refrigerator. We replaced the four 6V lead acid batteries (Serial/parallel configuration) that had around 200Ah of usable power or up 2400Wh. Of course we would never get to 2400Wh because of Peukert's law. Our initial upgrade was for four 12V 100Ah LiFePo4 batteries. This reduced the weight from about 240lbs to 120 lbs., improved the usable power to over 5kWh, and reduced charging time. (LiFePo4 has a much better charging profile than lead acid). The additional capacity deduced stress about needing to charge the batteries because of the refrigerator. The next upgrade was to add solar. We added six 200W solar panels to the RV. We working with a budget and decided to create a design that would allow us to add two additional panels in the future to increase from 1,200W of solar panels to 1,600W. This was in a configuration of four on one solar charging controller and two panels on another solar charging controller. The panels are wired in series to increase the voltage and permit smaller cabling. The other change is we upgraded the inverter charger to permit the entire RV to be powered. Originally the inverter was used for the refrigerator and a couple of outlets through the RV. Combined with adding soft start devices for our RV AC units, we now can run anything in our RV off the batteries. The goal was to be able to run the AC units overnight when we need a little cooling while dry camping or a couple of hours during the day while we were a way to keep our pets safe. (We also have an auto gen start if the batteries run low as a precaution.) One additional consideration is the power draw of Starlink. We use Starlink when we cannot get cellular internet service. As it turns out it draws more power a day than our refrigerator. Starlink also has a continuous draw. We reduced the daily use by putting it in sleep mode about 5 hours per night. To fully realize our system we added an additional four LiFePo4 100Ah batteries to expand our power capacity to over 10kWh of capacity. This is the configuration we used to travel to Alaska this year and spend over four months traveling through Alaska and spending a lot of time try camping. The only time we had to use our generator to charge is when the weather did not permit effective solar charging. On good days we would be fully charged by early afternoon. We also purchased a Ecoflow Delta 2 as a portable power source so we can have the flexibility to permit me to work if the RV is located in a location with a lot of tree cover. We can take the Ecoflow way from the RV in camp and setup the Starlink and charge my laptop while I work through the day. If required I can pack all of it up in the car and drive to a location to work. It is not uncommon for people to stop and look or ask questions when I have the Ecoflow, Starlink, and my laptop setup on a picnic table working. The 1kWh or battery provides enough power for me to get through a workday with Starlink, laptop, and charging my phone.
A few small lessons learned while boondocking on solar: 1.) Put an equal amount of thermal mass in both refrigerators. The chest fridge doesn't care but the upright should use less energy recovering from door openings. A couple cases of beer make a good foundation. ;) 2.) Put the Ecoflow in stand-by mode or turn it off altogether and only run it periodically to maintain a "safe" temperature, reducing unnecessary compressor run time. That could save 250-300Wh. 3.) In most refrigerators a power cycle will reset the defrost timer. This will prevent the upright refrigerator from using unnecessary power defrosting the freezer. The chest fridge doesn't have a defrost cycle so it saves energy right off the bat. I'd bet a dollar that you can reduce the total daily consumption of the large/Delta Pro setup by 30-40% with a few small tweaks.
I did an energy consumption survey on my house two years ago, my Samsung side by side refrigerator pulled a peek of 460w when in defrost mode, 380w in-rush on compressor motor start and average around 80w running with the door closed and 100w with the door open and lights on. All in all, my 2.5hp grundfos well pump is the largest load in my house after putting a soft starter on my 2ton ac unit.
after looking over the hourly electric meter readings (exported from the electric company) of our home for the last 8 months, we've got about ~650W of constant draw at any given hour, I'm still taking kill-a-watt readings of some appliances but 158W from 3 out of the 5 of our food/drink appliances.. minus some other stuff around the house, I'm still short 200~300W being accounted for. I made sure the temps were ~37F or ~0F inside them to cut down any unnecessary draw but the biggest unknowns are the [newish] central air system with an electric filter. I think the biggest surprise was the HEPA filter on fullblast was ~150W (two fridges or three freezers worth), but on minimum it's still as much as our fridge. We buy cows/pigs from a farmer, processed by butcher, stored frozen here (some risk on our end but we count maybe 3 days a year for power outages, fixed within 24h). I was considering solar+battery to cover this constant draw to potentially minimize the electric bill (rates increased ~30% this year), the pattern of our usage is 'food needs to be cold' so it's not really going to change for the next 10~20yrs, so thank you for mentioning that bit about the inverter needs to cover its own cost of operation and how much it may need. perhaps I'll have to start flipping breakers overnight to find the last bit unaccounted for, it's harder to do that with so many appliances already deployed on different circuits.
I use the emporia meter inside my breaker panel to get readings from any circuit, including water heaters, dryers and the AC. It only monitors 16 circuits, so some breakers I had to omit. I was surprised with how little some appliances used (living room TV), while my kitchen light (while in use, which is most of most days) uses a bunch. 4' fluorescent bulbs suck lol. (But equivalent in brightness LEDs are only about 15% more efficient, so I can't justify replacing until the bulbs fail). Also, when using a thermal camera I was astounded to see the heat generated by every wall wart power brick....
So looking at your electric meter, you can get very accurate results. Many electric meters have little dots on the bottom, each dot represents one watt. These are consumed as they move across the display. With a stop watch (phone app), you can get very accurate readings. You stand out there and count the dots in say 60 seconds. (10 dots in 1 minute is 600 dots/watts in 1 hour). Turn off all the circuits, then turn them one one at a time, (and give them a few minutes to stabilize) and see which circuit is using how much. You can then unplug everything from the circuit, so only one item in the home is plugged in and get an electric reading from you main meter. One could also wait a period of time (like half an hour... and see how much the cumulative reading goes up, but you need to make sure your meter is accurate enough.) By plugging in and unplugging various items, you can account for a lot. My electric water heater, then HVAC are the biggest draws. As far as the HEPA filter toss a filter on a box fan on low, or explore one the many furnace filter box "Corsi-Rosenthal boxes" (cheaper and better) and you can make one with ultra low power usage (computer fan).
@RNGwhydoihavetoregis If you're trying to offset your usage........get 800 watts worth of panels. Just be sure that your utility meter does not run backwards.
i have a 54quart 12v dc fridge which i got for 100 bucks. turns out it runs fine on 28v and hooked it up to a high efficiency gan 140w power adapter through a pd 3.1 trigger board at 28v. with some additional modifications like covering it in aluminum foil tape, I got the power usage down to 150wh/day lol. no inverter needed and if your pulling from a power bank you dont even need the gan adapters which loose about 6-7% efficiency. by your math i only need like a 50w solar panel lol. 100w would probably be more ideal. i think those are like 30-40 bucks now. i should probably make a video about my setup. aint no body never heard of a usb-c powered fridge.
Cool. You mentioned maybe wanting to use worst case numbers for solar radiance to be safe. That's smart especially for some places, but one thought I had is; many places with low solar radiance in winter are often cold enough that, if you have a power outage, you can just put the stuff outside in the snowbank or porch. So you might not always have to use the lowest numbers there.
Nice video. I liked the calculation tutorial. One thing to work into another video like this, besides running the test for a week or two, is to make sure the appliances are plugged into the EcoFlow units with 25' to 50' extension cords since most people will not be able to place their fridge right next to their EcoFLow.
Yeah, like some have mentioned, you need to include the thaw cycle if you have a frost free refrigerator. On mine, it's about 400 watts for about 30 minutes. Not completely sure how often it happens but it's at least once a day. And the start current on my fridge (which runs at about 120 watts) peaks at about 1800 watts for a fraction of a second.
Maybe I should build a "Soft-Start" unit for my fridge. Naaaa, to much brain power. I recently installed a "Soft Start" on my HVAC for running on my portable generator during power outages. The inrush dropped after installing the Soft-Start from 94 Amps to 24 Amps. Not as harsh on the compressor as before, the HCAC is 20 years old this summer. Trying to keep it running.
The defrost cycle on modern refrigerators are timer initiated and temperature terminated. The timer normally cycles every 8 hours. Defrost is terminated by the temperature of the evaporator coil. Although the defrost cycle might run for 20 minutes the actual defrost heaters located in the coil may only operate for 8-12 minutes, depending upon the build up of the ice. When the defrost cycle is operating normally, it only operates as long as necessary. Defrost heater cycles are longer in high humidity environments or when the freezer door is left open or does not seal properly. I've run my GE refrigerator, off grid in the Colorado mountains, for almost 20 years now on 8 ea. 130 watt panels and a 1,100 watt wind generator..... Occasionally I require the use of a gas generator back-up.
@@torainbowsend Back in 2022 our 14 year of fridge died. My wife wanted a GE Profile fridge, so I purchased her the one that is all decked out with WiFi, remote access and well if it was available that fridge has it ($$$$). I am surprised that it did not have StarLink on it. Since she does all the cooking and all fridge related topics, I figured go for it. A happy wife is a HAPPY LIFE!!!! I read your reply and I can only speak for the model that we have and for one, there is no timer initiated defrost activation and or deactivation. I pulled up the Energy Management dB for when we were up in the mountains for 3 months last summer and there was no sequence of time spaces between the time and days it was activated. Also, there was no rhyme or reason to how long defrost mode ran. There were times where there were 2 days between defrost mode and a couple with 4 days. There was no set block of time morning, afternoon or night that the defrost mode was activated, it was more random. As for the fridge's environment, the house indoor temperature was a constant 80-81 degrees per the ecobee dB that I download each month (for the last 5 years). The humidity in the house for the time we were away was 37 to 42%. The fridge doors were never opened during those 3 months. No clue as to what triggers the defrost mode on this model and with the 14.3kW EG4 battery that arrives next week it should not be an issue.
Thought I would add somewhat related info describing what I have going on at the moment. I have two Ecoflow Delta 2 Max units. Each one has a 2048 Wh capacity with a 2400W continuous output and a surge of 4800W. Following are the specs as measured by my PN2000 watt meter for my fridge and my stand-alone freezer. The meters were on the units for over a week to try to catch all the intermittent cycles. Café Energy Star 27.8 Cu Ft Smart 4-Door French-Door Refrigerator = Average KwH 0.0664 / Daily KwH = 1.5944. Frigidaire 13 Cu Ft Upright Freezer = Average KwH = 0.0376 / Average Daily KwH = 0.9014 The Delta 2 Max will run the fridge for approx. 21 hours with no input and the freezer for 38 hours with no input. (I’m guessing the missing 0.4 KwH on the fridge is being used by the inverter.) I just had two GSD7G72M-550WT panels delivered and hope to get them set up this weekend. These are 550W Bifacial panels with a VOC of 49.92 and a ISC[A] of 14.00. The Delta 2 Max will accept up to 60 volts and 15 amps on each 500W input (1000W total PV input per Delta 2 Max) so I should be able to keep these boxes running even under less-than-ideal conditions. Oh, I’m in the Phoenix, AZ area.
I would like to see a national campaign to advocate for inexpensive soft starts to Blunt the inrush. I know there are some relatively inexpensive ones for things like circular saws but the ones designed for a normal AC circuit are obscenely expensive period just my 2 cents
I have a large, 12-volt refrigerator in my camper. Two lead acid batteries could not keep it running overnight. Four 200 watt solar panels and 3 lithium batteries fixed the problem.
One comment about the sizing of the panels. Your calculations were great for clarity but you did calculate a 3day battery holding capacity and a 1 day recharge capacity. Frankly, you could cut the panel capacity in half and theoretically keep up. For other reasons, I’d use your numbers, though to rebound as quickly as possible. But the other recommendation I would make is look to the pricing. If your calculations suggest 1200 watt panel capacity but you can buy and size a great 1000 watt system, I’d say do that and pickup a small, portable generator and keep a “weeks worth” of gas on hand. In January or super cloudy times, you may run the generator a couple of hours every 2/3 days to replenish. What I like about that is you can double up and run the generator when you need to use power tools or a water pump or a pressure washer, etc, and you don’t have to run a generator at night. Another factor is that over sizing your system a little is wise. But, as you grow the system for more functions (lights, cameras, entertainment, etc), you can thin out the margin of safety because they should not all need extra at the same time. Plus, the more devices on the system the more options for picking and choosing what to power down for the sake of prioritizing other devices. But, this is a great presentation and the importance of factoring loss is huge. Thank you for mentioning that!
Great idea, I think I'll try it. A note of caution: If your in a situation of high ambient temperature, and especially, humidity, the evaporator will accumulate ice more quickly, and therefore, require a defrost cycle more often, failure to provide this will cause the refrigerator section to loose cold air flow because of the clogged evaporator. The freezer section will probably still operate sufficiently though.
NREL has a calculator that allows you to get solar input data specific to your address, panel orientation (which way they are pointed and the angle they are mounted at. That calculator also has average weather data built into it. Yes, do use the December results if you want an adequate solar array to provide the power you need all year. You also need to take things like shading from trees into account. I am in Maine and my 1,000 watt solar array does not provide enough power to run my fridge and chest freezer in Winter. To get around that I have a 20 Kwh battery bank. Also those all in one units are terribly inefficient. I have a 4,000 watt continuous, 6,500 watt surge split phase inverter and it only consumes 18 watts at idle for 204 watt-hr per 24 hour period. Finally, when sizing your solar array for one of those all in one units be mindful of their maximum solar input. I think the maximum solar input for the Delta2 1,000 watt unit is about 500 watts.
When you talk about fridges, the ambient temperature should be noted. Looks like they are in a garage maybe? What is the low, high, average temperature during your test?
I purchased a unique 13 cubic ft fridge freezer fridge dc power. It is running on 2 battle born 100 ah batteries and 2 200 watt solar panels. 40amp victron controller. Completely off grid. Works awesome.
If you take control of the fridge power youself (more recommended for basic fridges), then instead of the fridge turning off it's compressor, you just shut the invertor off entirely, you will save a lot more power. You will need a bit of "integration code" to link the invertor smarts to your own tempsensor though.
One comment about solar availability, a heavy overcast winter day results in the solar panel putting out 1/14 of its official power rating. The good news is that keeping food cold in the winter is easy. 😉 the covered porch runs about 20 to 30 F.
THANK YOU! Other than explaining to me why I don't want my fridge to die you did not veer off into odd territories. So it was very straightforward and easy to understand! Liked and subbed
Your videos are always excellent. I am not sure why you have not broken through the algorithm game and have 500K subscribers. Well done. Just a suggestion, no one has really attempted to use a 12/2 UF-B at 250 Ft (at less than 20 amps) as a replacement for PV wires to see the voltage degradation and compared that to PV 8 or 10 gauge. It would be a cool experiment.
I don't have quite that long of a run from my solar arrays to my solar controllers, but I used 4AWG wires and don't see any Voltage drop to speak of. If you are talking about solid core wiring, like in housing, it is less efficient than multi-strand wires of the same guage. As I understand it, because the electrons run along the outer surface of the wires, rather than inside, the more strands in the wire, the easier for electrons to travel, thus more power/Voltage transmitted.
We chose a smaller fridge with manual defrost, and its only drawing 100w when running. Get sun most of the time, so 2 x 300w panels is sufficient for us.
I just did a test with a Bluetti AC180 with a single Bougerv 180 watt solar panel running my full sized fridge. I used the fridge as normal and was able to run it for 24hrs with 20% left on the Bluetti. I don’t have much space for solar panels, so I plan to replace single 180 with 2 200w panels, then use multiple power stations, swapping them out as needed. I will eventually have 4 power stations (or extra add-on batteries) of at least 1000wh each ready for an emergency. I think this would keep me going for a while. For now I also have a small inverter gas generator for charging the stations if too cloudy. It will also keep a small window ac going during the summer. Yeah, get a gas generator and window ac for summer and a propane heater like a Mr Heater Buddy for winter. It’s also good to have a transfer switch to easily connect your power source.
Update: I did a second test with full sun on day 1 from 11am - 5:30pm, and the Bluetti maintained near 100 power all day. By 6am the next morning it was at 26%. Under mostly cloudy skies on day 2, it was getting an average of about 50 watts out of the 180w panel, which was enough to keep the battery at around 15% all day, until it finally died just before 8pm. That’s roughly 34 hours running a full sized fridge. With a few sunny days straight, it could run for quite some time. Fascinating!
Just a thought..instead of getting multiple power stations, pick up a 48v server rack battery with 5100wh and plug it into your solar input on your AC180. Unless you really need more solar power stations of course.
Good introductory exploration of sizing. Illinois is a reasonable testing ground, too, since their policies will make power expensive, as it is in California. Your costs in Illinois would be good for beginners, too, especially since prices/costs are always changing.
I'd recommend a sample of at least a week. One day is not going to accurately project weeks, months, years. E.g. On the weekend everyone could be home opening and closing the fridge all day.
Chalk it up to OCD-or forgetting I had the meter in place!-but I recorded the draw of a fridge I once used for over 500 hours. Then you can break down the total in more useful averages, e.g., by month or week or day.
For a system that has been running for more than 6 months. My refrigerator will use 1.5 k Watts hours in a day. 1200 W of solar, 48 V 100 amp battery. Average 4 to 5 1/2 hours of sun per day. We'll run for 2 and a 1/2 days.
The small inverter's standby power loss is more than the small fridge's power consumption, and the larger inverter consumes 50% of the power that the large fridge uses. Because the inverters are so wasteful of power, @qinarizonaful suggested using DC fridges that do not require the DC-AC inverter.
Where I live the solar irradiance numbers are horrible in Dec/Jan. The good news is that a refrigerator isn't needed from Nov-March ;) Another thing to consider in your numbers is if you're putting new items into the refrigerator.
8:30 finally, someone who is using nearly as much open tabs in his browser as i am 😂 today, because of renovating a bathroom, i opened the 3rd window because i cant substain the overview on the tabs anymore. Nice video thank you
Back in 1994, I bought a I4.5 cubic foot cycle, defrost refrigerator with the freezer on top for $ 175.00. The refrigerator had an evaporator coil and during the off cycle the coil in the refrigerator would defrost from the ambient 38° temperature. A small resistance heater on the evaporator coil would turn on when the compressor was off to make sure it would defrost in a hot humid environment. I disconnected this heater. I insulated the outside of the Whole refrigerator and consumption dropped to 0.750 KWh a day. After 30 years, this refrigerator is still operating only to replace the start run relay and the thermostat for $ 50.00. The top freezer of this refrigerator has to be defrost 3 to 4 times a year but not the bottom refrigerator, therefore cycle defrost naturally. Refrigerators don’t last long today about seven years. By modifying this refrigerator, I probably saved over $10,000 in 30 years which translates to $30,000 when invested in an index fund. Back in 1994 I did put in a 240 watt Solar system. Used batteries, then went to Trace micro inverters.
Long term, you'll probably want to double or triple the solar panels, and make sure the power station can run the fridge for at least 24 hours in case you get a lot of cloudy days in a row.
Not All fridges operate the way you described with short duration peaks followed by longer periods of low/no load. Newer inverter driven compressors will run longer durations at lower power as this is more efficient.
Nice video and testing. The department of energy actually has standardized testing methods and requires a label in every fridge. Most of them come in at average 2 - 2.5 kw-hr per day.
The more modern refridgerators/freezers are much better in power use and likely have smaller and more efficient compressors. It is often well worth replacing an older one with a newer one before you even look into solar panels and battery storage. The same for many other older appliances and of course insulation for the home. Same for hot water heating. If you can put in a hot water pre-heater to use the sun light directly for the heat then you can avoid a lot of expense and I would do this before putting in solar panels, but if you size the hot water system right and leave expansion room to add more panels then you've covered both bases. During the last spring we had a power outage for some time and I have a battery backup unit for my computer. I was worried that some things in the freezer would not be very good if they thawed too much so after an evening of no power I took the backup unit and plugged the fridge into it. The power draw was low enough that the fridge was able to run for half an hour on what remained in the battery backup unit. The battery backup unit has a power meter built into it which told me how many watts were being used. The most important thing was what you noted, don't open the fridge/freezer as much as possible. Another good things to know was to have the freezer as full as possible before the power outage. So if you commonly have a lot of empty space in the freezer you can put containers of water in there to add to the thermal mass until you need the space for other things. I cannot put up solar panels at the moment, but someday I hope to put some kind of system in. To remove a lot of the drain of running just a refridgerator/freezer solar and battery system you could put it on a timer which would cycle only enough times during the day to run the system but would avoid some large fraction of the drain of the inverter being on continuously.
Using a phase change material or even just loading the unit up with some thermal mass can dramatically change how often the thing cycles. You could probably turn the power off on the fridge for big stretches overnight using a timer, then turn it back on an hour or two before sunrise so it taps the batteries most *before* solar charging and load become available (charging is more efficient when batteries are lower than 80% or so,.and the most efficient use of solar is to run the fridge while the sun is out, avoiding the battery).
I have a 30qt fridge/cooler that I run in my truck, and a 220wh battery lasts between 8-12 hours sitting in the seat of my hot truck in Florida, with the temp set to 37°f. If I let it run all night on that battery, it only uses about 40% on average. I have connected a 100w foldable solar panel to it when at the beach, and that panel keeps the battery at 100% with the cooler set to 34°f. This is with the solar panel laying flat on the ground or leaning up against the cooler.
My fridge freezer runs on 80-90 watts but pulls at least 1200 watts on start up. That's going to be very hard on inverters. I went for a victron 1200 VA unit for that reason as it's a low frequency inverter with a 2400 watt surge capacity. You can hear the transformer buzz when the fridge kicks in.
We've been off-grid for 7 years now. The best someone can do is shop for the most efficient unit. Smaller doesn't always mean it uses less power. Our chest freezer is 4x or 5x bigger than the one you have there and uses only 95 watts max! Not a typo, 95! I have the same plug in meter you are using to watch and measure power usage. ( That's the surge power. I was floored) Our 55" flat screen smart TV only uses 30 watts to run . (TV was only $300 at Walmart, still operates perfectly) Even when people come to me wanting to add/go solar to lower their electricity bill. I ALWAYS tell them to look at reducing consumption first. Even if they have to go buy new appliances to achieve it. Often spending a few $100 here or there can save several hundred in power in a year. Also we bought 5 100 watt panels off Amazon thru the past few years for only $50-$60 each. They work GREAT!!! They charge our 12v lighting in our house and 12v led strips in my shop.
That's what we did on our off-grid homestead in the Ozarks... reduced consumption then sized solar panels for our needs. To reduce consumption we use LED lighting and chose to do without a dryer, dishwasher, and a microwave. Our earth sheltered home doesn't need HVAC. We use a woodstove for cooking, heating hot water, and comfort. We took it a bigger step farther in the reduction of consumption by using a small freezer and a straight refrigerator ( no freezer). Most of our stored food is in the cold room, cellar, and spring house. The dedicated refrigerator is for the eggs and produce that we sell locally. We have an indoor garden that provides a selection of fresh vegetables, year-round. I still remember how to prep and store meat and dairy without refrigeration. Venison and smoke cured ham hangs in the cold room and dairy is turned into salted butter and cheese. A cold room is pre-refrigeration design feature that modern homes no longer include. It is the coldest basement room that is vented to allow warm air to escape and cool air to enter. It can get to about 40 degrees and is safe for short-term storage of hanging meats and butter. We mostly can fish and meat for longer term storage and we eat a mostly plant-based diet anyway.
The cheapest watts in a offgrid/solar system are the ones you remove from the drain side. If you remove a drain of 100W per hour, you can reduce your solar panels with 500W and your battery with 1000W, atleast. (simplified for sure) And inverters are lossy as fuck, not if you look in the datasheets, where they often are tested at their most efficient point in the loadcurve, but in real life where I live, the loads are never constant, so they will never stay at that point. So start with redusing usage, removing parasite loads, and run everything you can on DC
I get my panels 20 at a time from China, 100w 100 bucks, but you have to get at least 20.. Gave up on electric fridges, I got a propane fridge (about 20 bucks a month)and stove, now we have so much power, we got a microwave..
Suggestion to interested solar array / photovoltaic power seekers. When considering or setting up... consider going dc to dc when ever possible DC ACs DC fridge etc... DC powered appliances are available... going dc to dc will create an almost lossless system.
I was trying to get a 12v DC/24vDC refrigerator to avoid some of the losses by cutting out the converter but those things are surprisingly expensive for their size.
If you have the refrigerator already then you can get the compressor replaces to a 24V DC one. It is for sure the way to go if efficiency it what you aim for, the idle looses when using an inverter for a refrigerator is a bit on the high side.
Cheap inverters and cheap fridges have those horrendous efficiency ratings. It might cost you an extra thousand or two to get the energy efficient models but you will certainly get the money back in run time savings.(My 26 CUFT Whirlpool fridge uses what your little chest unit does!) It was expensive up front but has repaid itself many times now in running costs, even in Houston TX where electricity is cheap.
The Whirlpool pictured is VERY efficient (I have). It uses under 1.1Kwh per day. I had an RV fridge that consumed nearly 5Kwh/day. THAT was a drain on my 1500watts of solar. The Whirlpool effectively uses well UNDER 7% of my 15Kw battery capacity and allows me to run other systems. Now, mini-split still uses too much energy on COOL. DRY setting uses about half of COOL but I have to add electric fans to move the air around the RV. Having 2500watts or more of available solar would allow me to run the mini-split on COOL and replenish fully each day.
Running an inverter can certainly kill your battery. But if you run both the Fridge/freezer and the inverter off an Arduino, it can simply turn the inverter off and on as needed when the fridge/freezer hits a certain temp. An Arduino would cost much less power to run vs the inverter all day.
You may have a hard time to synchronize your Arduino (with a temperature sensor) with the refrigerators thermostat. Properly better to use a refrigerator with no electronic and then let the refrigerators mechanical thermostat start/stop the inverter.
EcoFlow has an automation feature for scheduling the AC on/off that I am starting to use. I am going to do an off-grid irrigation project and see if this feature works well with and without connectivity.
@@K2teknik. I had thought of that also, but it would need to start the inverter first and shut it off last. So a dual thermostat set at slightly higher and lower triggering points might be necessary.
@@bafumat It all depend on the specifics on the inverter, can it start with a load? I would think that you can modify your fridges thermostats circuit to use it to start/stop the inverter and then feed the fridge from the inverter instead of the thermostat, but it all depend how/if the present circuit can be modified, fridge circuits can be tricky to put it mild. But this idea will bond your inverter to the fridge and that may not be what most people want. If you absolutely want solar to feed your fridge then replace the compressor with a 24V compressor and run directly from the batteries.
I HAVE 4 DIY SOLAR GEN A 5000 WATT A 3000 WATT A 2500 WATT A 1000 WATT I RUN FULL TIME I LET THEM PAY FOR THEM SELF, HAVE GRID POWER IF CLOUDY DAYS COME WITH CHARGER ON THEM ALL PANELS ARE GROUND MONT ALL SO DIY BATTERYS NO BMS ONLY BATTERY BALANCER DOING GREAT , THANKS FOR ALL THE INFO
Overall, your presentation was excellent. The only difference I would do is stress a little more that over-sizing your solar is cheap, will compensate for slightly inadequate _expensive_ battery capacity, and will also make your _expensive_ batteries last longer by stressing them less. When over-sizing, I don't think doubling (especially for the smaller system) is too extreme; it also helps one get through cloudy weather. Edit: Also, it seems you tested them in a garage, which is probably appropriate for the small guy, but not so much for one that's likely to live all its life inside. However, it tends to come out in the wash, because when it's hot in the summer and it runs more in a garage, you'll tend to get more than your yearly average solar insolation; similarly, when it has less solar in the winter, the garage-based one will probably run very little. Of course, all this is location-dependent, which is the main thing which should probably be stressed.
Thanks Scott. Being a complete novice at all this, I have a question. How do you get that a watt hour (wh) equals one day’s worth of power usage? I would think that something that consumes 100 watt hours would take 2400 watts in a day. What am I missing?
Yeah, that is a bit confusing. Here is the exact timestamp that addresses that specific question ruclips.net/video/IYjNv63CMS0/видео.htmlsi=A7Un90rpzXUB4K35&t=260
Hi @jacksonbooth2462 he was converting KWH to Watts 1000 x .23 and 1000 x .90. That through me for a loop to until I went back and noticed the meters were reading in KWH not Watts. Hope this helps
If something consumes 100W per hour, but only runs at that Wattage for 15 minutes, the total usage over the 24 hour period would be 1/4 of the 2400 Wh, or about 600Wh.
Awesome video. Thanks. Have you considered doing the same detailed vid on some of the newer 12V refrigerators, so that the inverters are taken out of the equation.
I have been load shedding my full sized fridge with my Delta pro since Oct 2023. It snows where I am. I did have to go back on grid about a dozen times. (just for the night while I was sleeping) This spring in 2024 I added more panel wattage and two extra batteries. The rest of my house has been consuming about 76 kWh's from the grid per month. Right now they owe me just under a grand Cad on my combined power and gas bill. My 9000 watts of diy with permits solar has been harvesting 10 MWh per year since 2015. I now have an off grid array for the load shedding. It's a fun hobby.
There are many things to consider ...like using a chest freezer or chest fridge which allows you to access goods without losing all that expensive cold air..start up current..ambient air temperature where the fridge freezer is located ..ventilation around fridge/freezer..a more direct use of electricity rather than into battery and out of battery...inefficiencies everywhere..
Best to use a chest freezer with a temperature controller from Johnson Control, if you need a freezer too buy a very small chest freezer to add to. This setup is available in DC a chest fridge but it’s much cheaper to make your own. The only thing is it doesn’t work in the space your old fridge used to be.
Thermal insulate the fridge/freezer easily 50% more efficient. If someone is using a victron Inverter, there is a standby setting it only draws a watt or so, and awakes in (user defined) interwalls to check for a load, if there is non, it falls back to standby. Its also possible to turn an Inverter off at night. Will save even more
Great info, thx! Then... in a worst case scenario being zero sun for three days, the fully charged batteries have ya covered. Day four the sun begins to shine, and now the solar panels are able to chill with zero battery. In that worst case scenario, don't I need extra solar panels that could simultaneously charge the depleted batteries to get me thru the next nite?
The biggest challenge a fridge faces isn't the amount of time it's open, it's the amount of time it has to spend cooling something down that's just been inserted. If you want a good stress test, take a bunch of water jugs at room temperature and stick them in the fridge at once. Then measure the amount of energy it consumes trying to get everything cooled down. If you just want an idea about how long you can go during a power failure, let the jugs cool to the fridge's temp first, then run it on batteries. I find that having an RV-style chest freezer designed to run on DC is a handy thing to have around the house. It's built to be as efficient as possible and to also limit the inrush current it requires to spin up the compressor. It's also smart enough not to run the compressor at full speed when it doesn't need to cool a large mass down. Normally I run mine off just regular AC. But during power failures, I can keep it running for hours using relatively small power banks. And since it uses DC, there are no inverter losses.
the ON and OFF cycle also depends on ambient temperature and the fridge load. A fridge full of food has a better thermal inerthia than an empty fridge, and this leads to a lower power consumption, in case of a time limited power outage. Ventilation around the fridge also plays an important role in the calculation.
I don't understand how you used the NREL data to get this answer. The NREL value you found is 4.2 kW-hr/Day/m^2. 1.440 kW-hr/4.2 kWhr/m^2 leaves me with area but some how you got watts needed. I see that your values are for 3 days but I still don't see how you get your watts at the bottom of the table. Thanks. Great video!
That threw me too, then I remembered that most people imply that solar energy is around 1KW per square meter. If you replace "KW" in the numerator with "M^2" (because they are 'the same', then the "square meter" terms cancel and you're left with "hours per day" which is what he implied in his calculation.
Glad you did this. Some folks have a really warped idea that solar is some kind of miracle. Case in point the 'Solar Ferry' which appears to have about 20-30kw of solar on it. Now this is a ferry that has to fight currents, carry people and cars and do it reliably every day, on the West coast. Obviously 20-30kw equates to max 30hp motor that the solar can actively drive. Now the municipality is screwed and had to buy back their old diesel ferry. I've seen the same thing on yachts, with selling points like 'Silent Operation'..... yeah if you park it and only run the fridge. I'm not knocking solar, but a whole lot of people don't realize that his is all calculable. Top it off with losses to charge batteries, peak power etc.. 25% losses on inverters are common with similar losses on battery charging. Point is solar is really great, but it needs to be calculated properly and it really isn't that hard. Thanks again for making this great video showing some of the pitfalls.
Running a conventional household fridge from solar isn't the wisest use of solar in general. The compressors aren't the most efficient. I do understand the premise of your video is keeping food cold or frozen during a power outage with pre-existing refrigeration. I can contribute information based on portable 12/24 volt compressor fridges, as have been running such from small scale solar for the last 7 years in a 12 volt system in Australia. (Apologies in advance for using amps and Amphour ratings. This is how we calculated off grid solar up until the lithium entered with "watthour" ratings. I still prefer Amphour calculations). Was able to power 2 x Endgel fridge/freezers totalling 140 litres in capacity. A 60 litre and an 80 litre, respectively. The average daily sun was close to 8 hours with 5 peak hours in summer in Australia, obtained by keeping the panels pointed towards the sun. Running both as a fridge, 2 x 160 watt solar panels and 4x175AH AGM(two batteries would have sufficed) powered these two without issue in 40 celcius heat. Average power usage per day was between 30 to 40 amps combined, dependant on overnight temperature. There was amble power to spare running as fridge's. Running the 80 litre as a freezer instead, was a different story. It required two additional 160 watt solar panels for a total of 4 to maintain the batteries in that same 40 celcius day time heat(the nights rarely dropped below 25). The 80 litre Engel was set to minus 11, which is enough to maintain frozen foods(vegtables, sausages and kfc chicken) for the 2 to 3 weeks that it was in there. Meat was placed in the bottom. During the heat of the day the 80 litre Engel as a freezer ran continuously to maintain the minus 11 in that 40 degree heat. The compressor did not begin cycling off until roughly 9 pm. It continued to cycle on for between 40 and 50 minutes out of every hour until the internal temperature stabilised The power usage was around 70 to 80 amps per day. Hourly current draw was between 3.5 and 4.5 amps at 12 volts. Winter is far less of an issue here in Australia. 2 x 160 watt panels can run both, using one as a freezer. I obtained power usage data by using inline watt meters between each fridge and the battery bank. The watt meters were for 12/24/48 volt solar/battery systems. The advantage of a portable fridge like the Engel(popular in Australia), Bushman, Evacool, Waeco(terrible company), Companion and many other brands of varying quality and price, is they can run direct from a battery bank without an invertor in between. This system can be operated from a power station. That route is very costly compared to a diy solar batter system of similar capacity. The 4x175AH AGM cost 1000 bucks australian. Lifepo4 of comparable capacity at 12 volts, is 2000 buck australian. Please note, 7 years ago, AGM batteries were the best in sealed lead acid batteries for off grid solar systems. Today, these batteries have been replaced with Lifepo4 in favour of their lighter weight.
For a 200 Wh fridge (15 minutes on) + 25Wh consuming inverter, and a 250W panel, you need one 24V 100Ah battery, if you have every day 10 hours sunlight. I have it running 6 months now and with 2 panels, I also can run my PC for 8 hours daily. For the winter however you may need to double up 😅
In a long term power outage I'm going to "turn on" my grid tied inverters (with the main breaker OFF) and use the 24KW solar panel array to charge my delta 2 power plant and offset the power consumption of refrigeration. And in the winter I have a dual fuel generator that I can fire up to charge things up.
@@everydaysolar you need to consult an experienced electrician. I got a pure signwave inverter and 2 batteries along with loose solar panels to charge the batteries. Then with the main power breaker OFF I plug the 220vac inverter into the house 220vac plug. Then to get 110vac I have a step down voltage adapter. And use that to power refrigeration, tv, and solar generator when the sun is up.
The defrost is a heater.. so you can turn it on / off via external switch, or just manually defrost. You can also schedule defrost for noon when solar production is highest
I have a great way to keep my solar power exense to a minimum. I live in Alaska and we get very little light during the winter months (roughly October - March). I would need a massive amount of solar panels to satisfy the power needs of my freezer during the winter since it uses about 880 watts/day. So instead of buying a truck load of panels, I keep the freezer outside without power for most of the winter. On the few days when the temperature bumps up over 20 degrees I turn the power on to make sure everything stays frozen. I also freeze two 1-gallon milk jugs outside and put those jugs in my refrigerator to keep the refrigerator power cost down. I rotate the jugs every two days to make sure there is always a solid block of ice in the refrigerator. During summer we get lots of light and I only need a few panels to keep my LiFePO4 batteries at full charge. These little techniques don't eliminate my need for solar power entirely, but they cut the need and cost dramatically.
DIY Home Solar ( as low as $1.26/Watt) - geni.us/project_solar
Kil-A-Watt Meter - geni.us/ehGDWK
EcoFlow Delta 2 - geni.us/u46bT
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100W Panels - geni.us/x7Tet
Peak Solar Hours map - www.nrel.gov/gis/assets/images/solar-annual-ghi-2018-usa-scale-01.jpg
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Do not forget that once every day or so the modern fridges go into a "Defrost" mode. My GE, runs between 84 and 108 Watts, but at least 1 time a day it goes into a Defrost mode which can last up to 2 hours and stay at 315 Watts for those 2 hours. On my BrulTech Energy Management program it shows a rather large spike for that time frame. Normally the fridge mostly stays in the 80-90 range. On days where we were not home (vacation) the fridge averaged .8kW and on those days where the defrost kicked on it was 1.4kW. I have about 5 years of data by the minute.... lots of data
Thanks for the data about defrost mode. Never thought about factoring that in.
My fridge uses 600 watts to defrost, however I think it only runs for about 15 minutes. So you definitely need to factor that in.
The 24 hour Kill-a-Watt data will cover the defrost operation.
he ran a watthour monitor (which everyone should) for 24 hours.. I'd do 7 days though just to get a better idea. So it doesn't matter that it goes into defrost mode.
You can buy many fridges without this mode and just deal with the ice build up. They are way more efficient, energy wise.
My wife bought a modern side-by-side refrigerator and it uses about 104 W most of the time but in defrost it goes up just slightly over 700 watts.
A couple of lessons learned from keeping the fridge running during and after a hurricane -
1. Room Temperature matters the hotter the room the longer the fridge will have to run to maintain temperature.
2. I found as the days without grid power increased the longer the fridge would run per cycle (longest cycle period was 6hrs)
3. The fridge may have additional features that can add to your power consumption (defrost cycle, heat strip around the freezer door)
4. Fill dead space with water bottles 👍 this is just good advice from an efficiency standpoint but extremely valuable when attempting to power your refrigerator without grid power.
5. Consider limiting wasted power by cycling the system on and off. And use a cooler for items people may grab between cycles - this is where the frozen water bottles really shine 👍🥶👍
Also I had to phone a friend on this one - My fridge was off for 4hrs and I plugged it in and the compressor didn’t start. I Checked the wattage and saw it was drawing over 300w but did not appear to be running. My friend said give it 15min it’s probably in a defrost cycle 🤦🏻♂️ I had been dealing with so many other catastrophes that I automatically assumed the worst 😂 15 minutes later the fridge started running just fine. If the cell phones were down I would have emptied my fridge into a cooler and planned on grilling the next day 🍗🍖🥩🍔…😂
Great advice, living in the Panhandle Of Florida hurricanes is a way of life for us. With the advance notice, I try to freeze some gallon milk jugs of water to use to help keep things cool in the refrigerator and freezer, plus you have some cool drinking water. Hurricane Michael was a monster and we were blessed just to have a house standing afterwards. Best regards!
As a former Floridian (1960's) hurricane season we had a mantra "bring in the dog and garbage cans, tape the windows, get new batteries for the radio, fill the bathtubs. As to #2 on your list, if the fridge duty cycles were longer off grid, that likely is due to your backup power system having less Amp/hour capacity than the grid.
You forgot to complain about the missing torque values on the bolts and setting angles of the panels.
@@mikesakas ? It’s possible you were trying to reply to someone else but you have me curious what their comment was… 😂
I live on a solar independent offshore cruising sailboat with 400 watts of solar panels and 460 amphrs of battery storage. I have a refrigerator/ freezer I built out myself. The average retail refrigerator freezer is garbage. Consumers will not put up with 5”-6” of insulation and top loading, but that’s pretty much is what it takes to make an efficient refrigerator/freezer in the tropics. The boat is charged by 10:30am in the morning and can go for a week with no sun. Most of it comes down to proper frig. box construction and covering conductive, radiant, and convective heat flow properly.
Can you make a video please 🥺🙏
Yeah show us bro
If you don't care what it looks like then just glue 4 inch PIR insulation board to the outside of a normal chest fridge. Obviously don't cover any cooling fins or air vents. That'll get you close. You might be able to bend the pipes enough to move the fins away from the rear of the unit and get insulation on that face too. Just don't break any.
My biggest thing was learning the efficiency from the tracking vs non tracking panels.
I agree on the chest style, cold is heavier than hot so when you open it it stays in there instead of falling to the floor and sucking in hot air that has to be cooled down again. I would love to see a video of this I have seen sailboat videos and the fridge freezer is under the seats or is by the sink in the galley.
For anyone interested you can control the defrost cycle on a fridge. Unfortunately, it is not part of the fridge settings. About 5 years ago a fellow RVer bought a Frigidaire residential fridge for his RV, but noticed that the defrost mode was killing his battery setup when it would kick in. Knowing that I was into electronics he asked for my assistance and I downloaded the fridge's wiring diagram and set him up with a manual switch/relay to deactivate the defroster when on battery power. Still works like a champ. I even sent him a diagram on how to automatically switch the defroster mode off when dry camping.
That is a great idea 🤔 future video idea 💡. Thanks for the feedback!
@@everydaysolar it would be interesting to see
how much of a power difference there is
If the fridge and freezer were full
@@mhughes1160 Thermal mass, once the food chills down, they actually draw a bit less, not needing to cycle on and off as often
So a switch for the power feed to the defrost heater?
Did you just add a switch inline to the defrost heater coil (is that how a fridge defrosts?) to shut it off?
For frugal people who need only a tiny amount of fridge space, here is an alternative. We used to go on mid-summer vacations in Greece in our small two-person camping car. We used a tiny 18-litre (5 US gallons) Swiss-made fridge attached to the car battery. It uses the same efficient compression technology as a big fridge and is very well isolated. (The isolation probably takes in more than half of the total volume.) Moreover, it opens at the top, so the cold tends to stay inside even when the lid is open.
We set this fridge to very cold while using the car, even though that meant our (Greek) yogurt might freeze. We rarely stayed longer than 2 days in one location, always lonely locations with no electric power source. We always took the fridge off the car's battery to avoid getting stranded. We did not add new food to the fridge while stationary, and never opened the lid for more than a few seconds.
We obviously parked the car under trees, but even so it got very hot inside. The food in our fridge went from frozen to slightly above regular fridge temperature in these days. Occasionally we stayed up to 4 days in one place. This just required reconnecting the fridge once, on a less extreme setting, and letting it run for an hour off the full battery.
All these measures were perfectly sufficient. We also used common sense in other ways, and so we never had food going off for lack of refrigeration.
Show us how you did it on youtubes
@@raymondflavin8708 Sorry, that is not going to happen. Even if I did do videos for RUclips -- the fridge is now with my ex-wife.
But if you want additional detail to make it more concrete: the fridge (I guess technically refrigerator box) was a Waeco CDF 18.
Refrigerators are much more efficient when they are fully loaded and have reached the desired temperature. The door of a fully loaded refrigerator can be briefly opened to access the contents without causing a measurable drop in the temperature of the thermal mass. There is less cold air volume in a fully loaded refrigerator (because the contents occupy most of the internal space). On the other hand, when the door is opened on empty refrigerator, the heavy cold air drops to the floor and the ambient warm (or hot) air takes its place and the refrigerator must energize the compressor to restore the desired temperature.
It's mostly that air doesn't have a lot of mass and food does. So a tiny mass escaping isn't a lot of energy.
What you have said about the volumes is certainly true, but even if the volume didn't change when full, the amount of energy lost via the air is relatively small and quickly recovered by the heat pump.
Source?
You also have to consider the temperature of the room/location of where the refrigerator is located. People with "garage" refrigerators or freezers are using a lot of power to keep those doing their job. It's a two prong problem. First the insulation can only do so much in a hot environment. And secondly the compressor works less efficient because it uses the air in the location to transfer the heat from the coil in order to cool. The warmer the ambient air the harder the compressor has to work to keep the inside cold
Refrigerators use MUCH LESS POWER when running with NO contents!!
You're correct! I also keep freezer packs in my off grid fridge. On very warm days I remove the freezer packs and place them around my food in the fridge to help maintain the cold.
Useful information! We have a 20 cubic feet bottom-freezer refrigerator in our off-grid house. As several people below, I disabled the defrost circuit, and manually defrost the freezer section twice a year. I recently bought an additional freezer from Costco - an 11 cubic feet upright model without a defrost feature. Adjusted to -13°C (8.6°F) it draws an all-day average of 32 Watts continuous power - drawing around 80 Watts, then cycling off. Simple "bang-bang logic".
Others in the comments have mentioned the thermal mass of the contents.
For both freezers and refrigerators freeze gallon jugs of water and use them to fill up empty spots.
The thermal mass will help regulate the inside temperature and in the event of a true power outage or multiple days without recharging keep the contents cold minimizing the on/off cycles.
Yep, and water is one of the best substances for this, as it has a insanely high heat capacity (takes a lot of energy to warm and cool it).
Ice takes a lot of energy to change it's physical state back to liquid water again, so that's why it can be surprisingly effective under prolonged power outages. Although that's also why it also seems to take forever freezing it back the other way to ice.
Even better, I save the “single use” freeze packs often included in shipping frozen foods because they work over and over only the thin plastic bag they come in makes them single use. They freeze about 2-4 degrees lower than ice and have nearly identical energy requirements for phase transition on a volume basis meaning if you fill your extra freezer space with them they will actually melt first keeping your frozen items frozen.
@@hugegamer5988 I use large juice bottles filled with salt water.
They work great for cold bags for groceries.
Salt water freezes/thaws at 25F.
Lots of thermal mass there.
I use gallon jugs filled with a 50/50 solution of RV antifreeze and water. Freezes/unfreezes around 10F, is nontoxic, and helps keep frozen things frozen.
I had NO idea that the conversion form DC to power standard AC appliance was such an energy hog; the fact the small inverter consumes as much power as the fridge it was feeding into is shocking. Excellent content BTW; thanks!
Yeah, it is something most of us miss starting off. Knowledge is power 👍
Look into inverters, not just power station inverters. The bigger the inverter the bigger the "dead" load (idle consumption for being on). In the case of mppt solar charger-inverters a 2000w one might consume 25w per hour, a 3000w 25-35w per hour, a 5000-6000w 45-55w and bigger ones like 10000w 70-80w. That adds up a LOT since 24 hours in a day times that you have to subtract from your batteries.. Solar does help offset that in light hours but not all day, and some even don't have solar when using a UPS setup . Cheers
A chest freezer/cooler is ALWAYS going to be more efficient due to the fact of opening the lid (cold air sinks!) You don't have the outrush of cold air like you would on the upright fridge/freezer, so less airspace turnover on the chest. Additionally, you have to consider "thermal mass" as a buffer. It's NOT efficient to keep a completely empty freezer or fridge. Augment the thermal mass of the chest freezer by adding in 2-liter bottles of frozen water to keep the temperature variance at a minimum...keeps the system from working so hard and can also tide you over for those sunless days!!!
Truth, the chest freezer in my RV draws 250-1000Wh per day depending on ambient temps (40-120F)
the smaller dorm style fridge in the same conditions draws between 750-2000Wh per day
I run it on 700W collection, 12V300Ah battery and 3000W inverter.
The Panels sit flat on my RV and present an issue with snow in the winter, December seems to be the only month I have issues
We have a chest freezer from the 80's that was in the basement when we moved into our house. I've replaced the thermostat twice, but the compressor still sounds like it could run for another 40 years.
Anyway, besides how well-built older chest freezers are, I wanted to mention that we have always had about a dozen four liter milk jugs filled with water and two pieces of half inch plywood on top of them to provide a much easier to reach "false bottom" and provide several days of security for the contents in the event of a power failure. Thermal mass can definitely prolong unpowered storage time.
@@glitchr8r Also could keep several frozen bottles on hand to take out and put in the refrigerator to keep it cool if necessary!!! Having those extra bottles of frozen clean water also provides something to drink when they thaw out!!! 👍🏻
@@davidconner-shover51 Hi, could you refine your comment on "dorm style fridge" to include cubic foot of the unit? I'm looking to buy a 10 cubic foot dorm style refrigerator for my RV. Size matters.
@@jerrywiese9722 5.1 cuft, nothin special, a Wal Mart purchase
Fine tunes:
1. Where applicable, (portable, etc) A DC fridge will save you all the inversion loss and make it simple to connect a home brewed cheap battery pack for 1-2 days poor sun run time.
2. A capacitor in a box will solve start up draw on either system, so don't have to design to a power level you only cycle 6 times a day.
Great presentation! If you did the above, I'd love to know how much smaller you could tweak your power supply array for a similar DC fridge!
Hmmm... with most DC fridges being less efficient than AC fridges, that might just go the wrong way, trading conversion losses for inefficiency.
For rainy days or if in Alaska where you only get a few hours of day light.
I would just place the panels inside a shipping container- use super bright Cobb style l.e.d. Lights and use a ""Fernel lense" to boost the l.e.d. light into the solar panels.
Yes, you will lose some of the power from batteries at night time but get more in daylight!
Even using exr soar high output panels.
My experience has shown after building three systems, it’s best to have at least twice the amount of panels, batteries, and inverter just in case! Especially in the winter.
I would bet on three times. You also havevto account for capacitance of heat in the fridge. Fill it with water and it will stay colder than an empty fridge when you open it. To really save money set gallons of water outside to freeze in the winter then put them in the fridge.
I always compute what my max electrical power draw will be and then target 1.4 x number of panels at max power to equal that draw. The .4 addition accounts for the tracking of the sun.
@@ricksherman34
Also, unless your solar panels can adjust to the time of year, this is another reason you’ll need to over panel
@@simon359 This is why my panels are tilted more perpendicular during summer months.... I can afford to run "leaner" in the winter months since my AC isn't running full throttle.
My fridge freezer has been running on my Delta Pro, Powerstream inverter (the AC is never on, the PS inverter uses 16W), an EF smart plug and 1600W of solar for over a year now. For an entire year it used 339.78kWh and that’s using it normally, opening the fridge 10-20 times a day as a family fridge freezer keeping cool what’s in it, cooling what we put in it and regularly freezing pots of ice cream made in our Ninja Creami.
I now have another couple of smart plugs linked to the system providing power to the main bedroom and lounge for an Apple Mac mini, 32” monitor, a 55” TV, a 32” TV, a couple of iPads and iPhones along with the router and other vampire power draw devices. I also have the inverter set to provide 30W of power to my home circuit.
Only in the very depths of winter do I need to top it up at night with half price power from the grid, my power bills are essentially just the standing charge, the cost of top up and whatever we use in the kitchen for cooking.
Well worth the investment imo, especially given the now proven longevity of Lifepo4 batteries.
Scott - thank you for the discussion on consumption, watt hours, & capacity in detail that even a solar novice like myself can understand
I have an upright deep freezer and a fridge freezer combo, what I have found running them 24, 7 is that both together pull around 200 watts down to 100 watts when they both are idle, but when they are running it can go as high as 600 to 800 watts likely both defrosting at the same time, but a 24 volt 200 amp hour battery was not enough to take them through the night, I had to buy another battery so now I have 24 volt 400 amp hours of storage and 2000 watts of solar, so far its been able to keep them going day and night the battery bank gets down to around 60 percent overnight so more battery is recommended. This is being home and daily use doors get opened several times a day as well.
I performed a test powering my fridge for two hours, four times per 24 hour period.
I also ran a test similar to the ones used here. The differences in results were dramatic.
While the temp inside the fridge did vary two-three degrees more during the first test,
it was well within a safe zone for refrigerated/frozen foods. Moral: You can vastly
extend the time you can power a fridge by eliminating the inverter "idle" time.
nice, you could further design the fridge for the power source by replacing insulation with mass. If the walls are [say] 3 meters of mud it will run excessively for about 2 months and take as much time to heat up if the power is disconnected. As it doesn't really matter when the pump runs you don't really need a battery. Can just crank the compressor with wind or solar directly when it is available. Could even put the cooling inside the 3 meter wall of mud to get even more stable cooling.
I'm an engineer and I find all of this fascinating. I lived in southern California for decades and 40 years ago we even had parabolic solar water heater panels on our roof. Today we live on the Gulf Coast. We get plenty of sunshine, but have hurricanes that require some form of alternative electrical generation. I installed a 24kW Generac natural gas generator and an automatic transfer switch. I choose to leave solar gathering to the utility companies for economies of scale. While it's fascinating, without wasteful government intervention the DIY power generation concept doesn't make economic sense. In my humble opinion of course.
You live in an area that must be ready for hurricanes, and an alternative power source such as $9,000 of generator+installation is a must as long as it can accept propane tanks in a dual fuel arrangement. We have a mid 1980's gasoline generator that has only been used once: by a coworker about 15 years ago in the mountain fires recovery area. However, there is another factor, and it concerns the condition of the grid in each family's vicinity. The grid is teetering in areas, causes forest fires in others, and is the main problem with economies of scale, especially after a disaster. Look at Japan and the nuclear plant disaster. Six months later, plenty of families in the region still had no electricity. We have sun and a decaying grid in California, with fire danger, because the so-called public utilities companies have been investor-owned for 30 years. They refuse to invest in the grid. So, DIY can prevent long-term power disruption in a household.
You did aq great job presneting the information. This video is very relative to our situation. We went through a similar method when we sized our solution. We used a battery monitor system like the Victron BMV-712 to understand the power needs of our system in real world situations prior to upgrading batteries or adding solar.
We have a class A RV with a residential refrigerator. The original lead acid house batteries were challenged by the refrigerator. We replaced the four 6V lead acid batteries (Serial/parallel configuration) that had around 200Ah of usable power or up 2400Wh. Of course we would never get to 2400Wh because of Peukert's law. Our initial upgrade was for four 12V 100Ah LiFePo4 batteries. This reduced the weight from about 240lbs to 120 lbs., improved the usable power to over 5kWh, and reduced charging time. (LiFePo4 has a much better charging profile than lead acid). The additional capacity deduced stress about needing to charge the batteries because of the refrigerator.
The next upgrade was to add solar. We added six 200W solar panels to the RV. We working with a budget and decided to create a design that would allow us to add two additional panels in the future to increase from 1,200W of solar panels to 1,600W. This was in a configuration of four on one solar charging controller and two panels on another solar charging controller. The panels are wired in series to increase the voltage and permit smaller cabling.
The other change is we upgraded the inverter charger to permit the entire RV to be powered. Originally the inverter was used for the refrigerator and a couple of outlets through the RV. Combined with adding soft start devices for our RV AC units, we now can run anything in our RV off the batteries. The goal was to be able to run the AC units overnight when we need a little cooling while dry camping or a couple of hours during the day while we were a way to keep our pets safe. (We also have an auto gen start if the batteries run low as a precaution.)
One additional consideration is the power draw of Starlink. We use Starlink when we cannot get cellular internet service. As it turns out it draws more power a day than our refrigerator. Starlink also has a continuous draw. We reduced the daily use by putting it in sleep mode about 5 hours per night.
To fully realize our system we added an additional four LiFePo4 100Ah batteries to expand our power capacity to over 10kWh of capacity. This is the configuration we used to travel to Alaska this year and spend over four months traveling through Alaska and spending a lot of time try camping. The only time we had to use our generator to charge is when the weather did not permit effective solar charging. On good days we would be fully charged by early afternoon.
We also purchased a Ecoflow Delta 2 as a portable power source so we can have the flexibility to permit me to work if the RV is located in a location with a lot of tree cover. We can take the Ecoflow way from the RV in camp and setup the Starlink and charge my laptop while I work through the day. If required I can pack all of it up in the car and drive to a location to work. It is not uncommon for people to stop and look or ask questions when I have the Ecoflow, Starlink, and my laptop setup on a picnic table working. The 1kWh or battery provides enough power for me to get through a workday with Starlink, laptop, and charging my phone.
A few small lessons learned while boondocking on solar:
1.) Put an equal amount of thermal mass in both refrigerators. The chest fridge doesn't care but the upright should use less energy recovering from door openings. A couple cases of beer make a good foundation. ;)
2.) Put the Ecoflow in stand-by mode or turn it off altogether and only run it periodically to maintain a "safe" temperature, reducing unnecessary compressor run time. That could save 250-300Wh.
3.) In most refrigerators a power cycle will reset the defrost timer. This will prevent the upright refrigerator from using unnecessary power defrosting the freezer. The chest fridge doesn't have a defrost cycle so it saves energy right off the bat. I'd bet a dollar that you can reduce the total daily consumption of the large/Delta Pro setup by 30-40% with a few small tweaks.
I did an energy consumption survey on my house two years ago, my Samsung side by side refrigerator pulled a peek of 460w when in defrost mode, 380w in-rush on compressor motor start and average around 80w running with the door closed and 100w with the door open and lights on. All in all, my 2.5hp grundfos well pump is the largest load in my house after putting a soft starter on my 2ton ac unit.
a 2 hp well pump isn't completely normal. I'm guessing you have a fairly deep well or extremely high water usage.
My overnight tire pressure decreased in winter so no defrost cycles 😀
after looking over the hourly electric meter readings (exported from the electric company) of our home for the last 8 months, we've got about ~650W of constant draw at any given hour, I'm still taking kill-a-watt readings of some appliances but 158W from 3 out of the 5 of our food/drink appliances.. minus some other stuff around the house, I'm still short 200~300W being accounted for. I made sure the temps were ~37F or ~0F inside them to cut down any unnecessary draw but the biggest unknowns are the [newish] central air system with an electric filter. I think the biggest surprise was the HEPA filter on fullblast was ~150W (two fridges or three freezers worth), but on minimum it's still as much as our fridge. We buy cows/pigs from a farmer, processed by butcher, stored frozen here (some risk on our end but we count maybe 3 days a year for power outages, fixed within 24h).
I was considering solar+battery to cover this constant draw to potentially minimize the electric bill (rates increased ~30% this year), the pattern of our usage is 'food needs to be cold' so it's not really going to change for the next 10~20yrs, so thank you for mentioning that bit about the inverter needs to cover its own cost of operation and how much it may need.
perhaps I'll have to start flipping breakers overnight to find the last bit unaccounted for, it's harder to do that with so many appliances already deployed on different circuits.
did you forget an electric water heater or electronics being charged? anything outside that runs from an extension cord?
I use the emporia meter inside my breaker panel to get readings from any circuit, including water heaters, dryers and the AC. It only monitors 16 circuits, so some breakers I had to omit.
I was surprised with how little some appliances used (living room TV), while my kitchen light (while in use, which is most of most days) uses a bunch. 4' fluorescent bulbs suck lol. (But equivalent in brightness LEDs are only about 15% more efficient, so I can't justify replacing until the bulbs fail).
Also, when using a thermal camera I was astounded to see the heat generated by every wall wart power brick....
So looking at your electric meter, you can get very accurate results. Many electric meters have little dots on the bottom, each dot represents one watt. These are consumed as they move across the display. With a stop watch (phone app), you can get very accurate readings. You stand out there and count the dots in say 60 seconds. (10 dots in 1 minute is 600 dots/watts in 1 hour). Turn off all the circuits, then turn them one one at a time, (and give them a few minutes to stabilize) and see which circuit is using how much. You can then unplug everything from the circuit, so only one item in the home is plugged in and get an electric reading from you main meter. One could also wait a period of time (like half an hour... and see how much the cumulative reading goes up, but you need to make sure your meter is accurate enough.) By plugging in and unplugging various items, you can account for a lot. My electric water heater, then HVAC are the biggest draws. As far as the HEPA filter toss a filter on a box fan on low, or explore one the many furnace filter box "Corsi-Rosenthal boxes" (cheaper and better) and you can make one with ultra low power usage (computer fan).
@RNGwhydoihavetoregis If you're trying to offset your usage........get 800 watts worth of panels. Just be sure that your utility meter does not run backwards.
i have a 54quart 12v dc fridge which i got for 100 bucks. turns out it runs fine on 28v and hooked it up to a high efficiency gan 140w power adapter through a pd 3.1 trigger board at 28v. with some additional modifications like covering it in aluminum foil tape, I got the power usage down to 150wh/day lol. no inverter needed and if your pulling from a power bank you dont even need the gan adapters which loose about 6-7% efficiency.
by your math i only need like a 50w solar panel lol. 100w would probably be more ideal. i think those are like 30-40 bucks now.
i should probably make a video about my setup. aint no body never heard of a usb-c powered fridge.
Cool. You mentioned maybe wanting to use worst case numbers for solar radiance to be safe. That's smart especially for some places, but one thought I had is; many places with low solar radiance in winter are often cold enough that, if you have a power outage, you can just put the stuff outside in the snowbank or porch. So you might not always have to use the lowest numbers there.
Nice video. I liked the calculation tutorial. One thing to work into another video like this, besides running the test for a week or two, is to make sure the appliances are plugged into the EcoFlow units with 25' to 50' extension cords since most people will not be able to place their fridge right next to their EcoFLow.
Yeah, like some have mentioned, you need to include the thaw cycle if you have a frost free refrigerator. On mine, it's about 400 watts for about 30 minutes. Not completely sure how often it happens but it's at least once a day. And the start current on my fridge (which runs at about 120 watts) peaks at about 1800 watts for a fraction of a second.
The 24 hour Kill-a-Watt data will cover the defrost operation.
Maybe I should build a "Soft-Start" unit for my fridge. Naaaa, to much brain power. I recently installed a "Soft Start" on my HVAC for running on my portable generator during power outages. The inrush dropped after installing the Soft-Start from 94 Amps to 24 Amps. Not as harsh on the compressor as before, the HCAC is 20 years old this summer. Trying to keep it running.
The defrost cycle on modern refrigerators are timer initiated and temperature terminated.
The timer normally cycles every 8 hours. Defrost is terminated by the temperature of the evaporator coil. Although the defrost cycle might run for 20 minutes the actual defrost heaters located in the coil may only operate for 8-12 minutes, depending upon the build up of the ice. When the defrost cycle is operating normally, it only operates as long as necessary. Defrost heater cycles are longer in high humidity environments or when the freezer door is left open or does not seal properly.
I've run my GE refrigerator, off grid in the Colorado mountains, for almost 20 years now on 8 ea. 130 watt panels and a 1,100 watt wind generator..... Occasionally I require the use of a gas generator back-up.
@@torainbowsend Back in 2022 our 14 year of fridge died. My wife wanted a GE Profile fridge, so I purchased her the one that is all decked out with WiFi, remote access and well if it was available that fridge has it ($$$$). I am surprised that it did not have StarLink on it. Since she does all the cooking and all fridge related topics, I figured go for it. A happy wife is a HAPPY LIFE!!!!
I read your reply and I can only speak for the model that we have and for one, there is no timer initiated defrost activation and or deactivation. I pulled up the Energy Management dB for when we were up in the mountains for 3 months last summer and there was no sequence of time spaces between the time and days it was activated. Also, there was no rhyme or reason to how long defrost mode ran. There were times where there were 2 days between defrost mode and a couple with 4 days. There was no set block of time morning, afternoon or night that the defrost mode was activated, it was more random.
As for the fridge's environment, the house indoor temperature was a constant 80-81 degrees per the ecobee dB that I download each month (for the last 5 years). The humidity in the house for the time we were away was 37 to 42%. The fridge doors were never opened during those 3 months. No clue as to what triggers the defrost mode on this model and with the 14.3kW EG4 battery that arrives next week it should not be an issue.
Thought I would add somewhat related info describing what I have going on at the moment. I have two Ecoflow Delta 2 Max units. Each one has a 2048 Wh capacity with a 2400W continuous output and a surge of 4800W. Following are the specs as measured by my PN2000 watt meter for my fridge and my stand-alone freezer. The meters were on the units for over a week to try to catch all the intermittent cycles.
Café Energy Star 27.8 Cu Ft Smart 4-Door French-Door Refrigerator = Average KwH 0.0664 / Daily KwH = 1.5944.
Frigidaire 13 Cu Ft Upright Freezer = Average KwH = 0.0376 / Average Daily KwH = 0.9014
The Delta 2 Max will run the fridge for approx. 21 hours with no input and the freezer for 38 hours with no input. (I’m guessing the missing 0.4 KwH on the fridge is being used by the inverter.)
I just had two GSD7G72M-550WT panels delivered and hope to get them set up this weekend. These are 550W Bifacial panels with a VOC of 49.92 and a ISC[A] of 14.00. The Delta 2 Max will accept up to 60 volts and 15 amps on each 500W input (1000W total PV input per Delta 2 Max) so I should be able to keep these boxes running even under less-than-ideal conditions. Oh, I’m in the Phoenix, AZ area.
Wow. Informative. I live in Colorado and we don't have many days of cloud coverage. The southwest is ideal for solar panels.
I would like to see a national campaign to advocate for inexpensive soft starts to Blunt the inrush. I know there are some relatively inexpensive ones for things like circular saws but the ones designed for a normal AC circuit are obscenely expensive period just my 2 cents
3-phase to every home!
I have a large, 12-volt refrigerator in my camper. Two lead acid batteries could not keep it running overnight. Four 200 watt solar panels and 3 lithium batteries fixed the problem.
LOL, either solar is very inefficient or maybe you might want to try getting an energy efficient fridge??
Excellent video! I'm in the "crawl walk run" phase now with solar so this info hit the spot! Thanks!
One comment about the sizing of the panels. Your calculations were great for clarity but you did calculate a 3day battery holding capacity and a 1 day recharge capacity. Frankly, you could cut the panel capacity in half and theoretically keep up. For other reasons, I’d use your numbers, though to rebound as quickly as possible. But the other recommendation I would make is look to the pricing. If your calculations suggest 1200 watt panel capacity but you can buy and size a great 1000 watt system, I’d say do that and pickup a small, portable generator and keep a “weeks worth” of gas on hand. In January or super cloudy times, you may run the generator a couple of hours every 2/3 days to replenish. What I like about that is you can double up and run the generator when you need to use power tools or a water pump or a pressure washer, etc, and you don’t have to run a generator at night. Another factor is that over sizing your system a little is wise. But, as you grow the system for more functions (lights, cameras, entertainment, etc), you can thin out the margin of safety because they should not all need extra at the same time. Plus, the more devices on the system the more options for picking and choosing what to power down for the sake of prioritizing other devices. But, this is a great presentation and the importance of factoring loss is huge. Thank you for mentioning that!
I think you missed the point of the video...
@@twosencefromcleveland6084 probably not.
Great idea, I think I'll try it. A note of caution: If your in a situation of high ambient temperature, and especially, humidity, the evaporator will accumulate ice more quickly, and therefore, require a defrost cycle more often, failure to provide this will cause the refrigerator section to loose cold air flow because of the clogged evaporator. The freezer section will probably still operate sufficiently though.
Love the empirical approach.
NREL has a calculator that allows you to get solar input data specific to your address, panel orientation (which way they are pointed and the angle they are mounted at. That calculator also has average weather data built into it. Yes, do use the December results if you want an adequate solar array to provide the power you need all year. You also need to take things like shading from trees into account. I am in Maine and my 1,000 watt solar array does not provide enough power to run my fridge and chest freezer in Winter. To get around that I have a 20 Kwh battery bank. Also those all in one units are terribly inefficient. I have a 4,000 watt continuous, 6,500 watt surge split phase inverter and it only consumes 18 watts at idle for 204 watt-hr per 24 hour period. Finally, when sizing your solar array for one of those all in one units be mindful of their maximum solar input. I think the maximum solar input for the Delta2 1,000 watt unit is about 500 watts.
I've been looking for a reference like this. Great job in breaking it down so neophytes like me can understand it.
When you talk about fridges, the ambient temperature should be noted. Looks like they are in a garage maybe? What is the low, high, average temperature during your test?
I purchased a unique 13 cubic ft fridge freezer fridge dc power. It is running on 2 battle born 100 ah batteries and 2 200 watt solar panels. 40amp victron controller. Completely off grid. Works awesome.
Here in canada that is a $3000 fridge.
If you take control of the fridge power youself (more recommended for basic fridges), then instead of the fridge turning off it's compressor, you just shut the invertor off entirely, you will save a lot more power. You will need a bit of "integration code" to link the invertor smarts to your own tempsensor though.
One comment about solar availability, a heavy overcast winter day results in the solar panel putting out 1/14 of its official power rating. The good news is that keeping food cold in the winter is easy. 😉 the covered porch runs about 20 to 30 F.
The porch probably doesn't take very much wattage to run, either. lol
Covered porch for the win !!
THANK YOU! Other than explaining to me why I don't want my fridge to die you did not veer off into odd territories. So it was very straightforward and easy to understand!
Liked and subbed
Your videos are always excellent. I am not sure why you have not broken through the algorithm game and have 500K subscribers. Well done. Just a suggestion, no one has really attempted to use a 12/2 UF-B at 250 Ft (at less than 20 amps) as a replacement for PV wires to see the voltage degradation and compared that to PV 8 or 10 gauge. It would be a cool experiment.
I don't have quite that long of a run from my solar arrays to my solar controllers, but I used 4AWG wires and don't see any Voltage drop to speak of. If you are talking about solid core wiring, like in housing, it is less efficient than multi-strand wires of the same guage. As I understand it, because the electrons run along the outer surface of the wires, rather than inside, the more strands in the wire, the easier for electrons to travel, thus more power/Voltage transmitted.
AMAZING INFORMATIVE INFORMATION, THANK YOU 😇👍🏾
We chose a smaller fridge with manual defrost, and its only drawing 100w when running. Get sun most of the time, so 2 x 300w panels is sufficient for us.
More , the answer is always more solar and more battery s. You have to figure for cloudy days and stormy weeks.
Exactly, we had last winter in the north east Nevada only about 10 days of sun out of 68 days..need a 400 watt wind turbine too!
I just did a test with a Bluetti AC180 with a single Bougerv 180 watt solar panel running my full sized fridge. I used the fridge as normal and was able to run it for 24hrs with 20% left on the Bluetti.
I don’t have much space for solar panels, so I plan to replace single 180 with 2 200w panels, then use multiple power stations, swapping them out as needed. I will eventually have 4 power stations (or extra add-on batteries) of at least 1000wh each ready for an emergency. I think this would keep me going for a while.
For now I also have a small inverter gas generator for charging the stations if too cloudy. It will also keep a small window ac going during the summer. Yeah, get a gas generator and window ac for summer and a propane heater like a Mr Heater Buddy for winter. It’s also good to have a transfer switch to easily connect your power source.
Update: I did a second test with full sun on day 1 from 11am - 5:30pm, and the Bluetti maintained near 100 power all day. By 6am the next morning it was at 26%. Under mostly cloudy skies on day 2, it was getting an average of about 50 watts out of the 180w panel, which was enough to keep the battery at around 15% all day, until it finally died just before 8pm. That’s roughly 34 hours running a full sized fridge. With a few sunny days straight, it could run for quite some time. Fascinating!
Just a thought..instead of getting multiple power stations, pick up a 48v server rack battery with 5100wh and plug it into your solar input on your AC180. Unless you really need more solar power stations of course.
@@surfguy777 Thanks for the suggestion. I’ll have to look more into that.
Great info, i have worked out my fridge daily power usage but never factored in the inverter loss.
Good introductory exploration of sizing. Illinois is a reasonable testing ground, too, since their policies will make power expensive, as it is in California.
Your costs in Illinois would be good for beginners, too, especially since prices/costs are always changing.
I'd recommend a sample of at least a week. One day is not going to accurately project weeks, months, years. E.g. On the weekend everyone could be home opening and closing the fridge all day.
Chalk it up to OCD-or forgetting I had the meter in place!-but I recorded the draw of a fridge I once used for over 500 hours. Then you can break down the total in more useful averages, e.g., by month or week or day.
For a system that has been running for more than 6 months. My refrigerator will use 1.5 k Watts hours in a day. 1200 W of solar, 48 V 100 amp battery. Average 4 to 5 1/2 hours of sun per day. We'll run for 2 and a 1/2 days.
Thank you. This is what I was looking for.
Thanks for the video!
I didnt realize those portable power sourses were so inefficient
The small inverter's standby power loss is more than the small fridge's power consumption, and the larger inverter consumes 50% of the power that the large fridge uses. Because the inverters are so wasteful of power, @qinarizonaful suggested using DC fridges that do not require the DC-AC inverter.
Where I live the solar irradiance numbers are horrible in Dec/Jan. The good news is that a refrigerator isn't needed from Nov-March ;)
Another thing to consider in your numbers is if you're putting new items into the refrigerator.
8:30 finally, someone who is using nearly as much open tabs in his browser as i am 😂
today, because of renovating a bathroom, i opened the 3rd window because i cant substain the overview on the tabs anymore. Nice video thank you
Back in 1994, I bought a I4.5 cubic foot cycle, defrost refrigerator with the freezer on top for $ 175.00. The refrigerator had an evaporator coil and during the off cycle the coil in the refrigerator would defrost from the ambient 38° temperature. A small resistance heater on the evaporator coil would turn on when the compressor was off to make sure it would defrost in a hot humid environment. I disconnected this heater. I insulated the outside of the Whole refrigerator and consumption dropped to 0.750 KWh a day. After 30 years, this refrigerator is still operating only to replace the start run relay and the thermostat for $ 50.00. The top freezer of this refrigerator has to be defrost 3 to 4 times a year but not the bottom refrigerator, therefore cycle defrost naturally. Refrigerators don’t last long today about seven years. By modifying this refrigerator, I probably saved over $10,000 in 30 years which translates to $30,000 when invested in an index fund. Back in 1994 I did put in a 240 watt Solar system. Used batteries, then went to Trace micro inverters.
2:15 That's not how you calculate wattage used on an AC appliance, you also need to multiply by the power factor.
Long term, you'll probably want to double or triple the solar panels, and make sure the power station can run the fridge for at least 24 hours in case you get a lot of cloudy days in a row.
In a home installation, I would not put them on my roof. If you do, check with your home insurance provider to see if your insurance will be affected.
Soooo what was the final answer?
Not All fridges operate the way you described with short duration peaks followed by longer periods of low/no load. Newer inverter driven compressors will run longer durations at lower power as this is more efficient.
Nice video and testing. The department of energy actually has standardized testing methods and requires a label in every fridge. Most of them come in at average 2 - 2.5 kw-hr per day.
The more modern refridgerators/freezers are much better in power use and likely have smaller and more efficient compressors. It is often well worth replacing an older one with a newer one before you even look into solar panels and battery storage. The same for many other older appliances and of course insulation for the home. Same for hot water heating. If you can put in a hot water pre-heater to use the sun light directly for the heat then you can avoid a lot of expense and I would do this before putting in solar panels, but if you size the hot water system right and leave expansion room to add more panels then you've covered both bases.
During the last spring we had a power outage for some time and I have a battery backup unit for my computer. I was worried that some things in the freezer would not be very good if they thawed too much so after an evening of no power I took the backup unit and plugged the fridge into it. The power draw was low enough that the fridge was able to run for half an hour on what remained in the battery backup unit. The battery backup unit has a power meter built into it which told me how many watts were being used.
The most important thing was what you noted, don't open the fridge/freezer as much as possible.
Another good things to know was to have the freezer as full as possible before the power outage. So if you commonly have a lot of empty space in the freezer you can put containers of water in there to add to the thermal mass until you need the space for other things.
I cannot put up solar panels at the moment, but someday I hope to put some kind of system in.
To remove a lot of the drain of running just a refridgerator/freezer solar and battery system you could put it on a timer which would cycle only enough times during the day to run the system but would avoid some large fraction of the drain of the inverter being on continuously.
Using a phase change material or even just loading the unit up with some thermal mass can dramatically change how often the thing cycles.
You could probably turn the power off on the fridge for big stretches overnight using a timer, then turn it back on an hour or two before sunrise so it taps the batteries most *before* solar charging and load become available (charging is more efficient when batteries are lower than 80% or so,.and the most efficient use of solar is to run the fridge while the sun is out, avoiding the battery).
Free video very precise and moves right along. Thank you
I have a 30qt fridge/cooler that I run in my truck, and a 220wh battery lasts between 8-12 hours sitting in the seat of my hot truck in Florida, with the temp set to 37°f. If I let it run all night on that battery, it only uses about 40% on average.
I have connected a 100w foldable solar panel to it when at the beach, and that panel keeps the battery at 100% with the cooler set to 34°f. This is with the solar panel laying flat on the ground or leaning up against the cooler.
My fridge freezer runs on 80-90 watts but pulls at least 1200 watts on start up. That's going to be very hard on inverters. I went for a victron 1200 VA unit for that reason as it's a low frequency inverter with a 2400 watt surge capacity. You can hear the transformer buzz when the fridge kicks in.
Yeah, I know many off-grid guys caution using high-frequency inverters for loads like this. Thanks for the feedback 👍
We've been off-grid for 7 years now. The best someone can do is shop for the most efficient unit. Smaller doesn't always mean it uses less power.
Our chest freezer is 4x or 5x bigger than the one you have there and uses only 95 watts max! Not a typo, 95! I have the same plug in meter you are using to watch and measure power usage. ( That's the surge power. I was floored)
Our 55" flat screen smart TV only uses 30 watts to run . (TV was only $300 at Walmart, still operates perfectly)
Even when people come to me wanting to add/go solar to lower their electricity bill. I ALWAYS tell them to look at reducing consumption first. Even if they have to go buy new appliances to achieve it. Often spending a few $100 here or there can save several hundred in power in a year.
Also we bought 5 100 watt panels off Amazon thru the past few years for only $50-$60 each. They work GREAT!!!
They charge our 12v lighting in our house and 12v led strips in my shop.
That's what we did on our off-grid homestead in the Ozarks... reduced consumption then sized solar panels for our needs.
To reduce consumption we use LED lighting and chose to do without a dryer, dishwasher, and a microwave. Our earth sheltered home doesn't need HVAC. We use a woodstove for cooking, heating hot water, and comfort.
We took it a bigger step farther in the reduction of consumption by using a small freezer and a straight refrigerator ( no freezer). Most of our stored food is in the cold room, cellar, and spring house. The dedicated refrigerator is for the eggs and produce that we sell locally. We have an indoor garden that provides a selection of fresh vegetables, year-round.
I still remember how to prep and store meat and dairy without refrigeration. Venison and smoke cured ham hangs in the cold room and dairy is turned into salted butter and cheese. A cold room is pre-refrigeration design feature that modern homes no longer include. It is the coldest basement room that is vented to allow warm air to escape and cool air to enter. It can get to about 40 degrees and is safe for short-term storage of hanging meats and butter. We mostly can fish and meat for longer term storage and we eat a mostly plant-based diet anyway.
The cheapest watts in a offgrid/solar system are the ones you remove from the drain side.
If you remove a drain of 100W per hour, you can reduce your solar panels with 500W and your battery with 1000W, atleast. (simplified for sure)
And inverters are lossy as fuck, not if you look in the datasheets, where they often are tested at their most efficient point in the loadcurve, but in real life where I live, the loads are never constant, so they will never stay at that point.
So start with redusing usage, removing parasite loads, and run everything you can on DC
Can you share the chest freezer brand and model?
I get my panels 20 at a time from China, 100w 100 bucks, but you have to get at least 20..
Gave up on electric fridges, I got a propane fridge (about 20 bucks a month)and stove, now we have so much power, we got a microwave..
@@larryscarr3897 Ok, thanks for the info.
Good job with this Scott. We love our solar panels and it helps our company to be independent for the future!!
would love to see if you numbers change if they are full of food and drinks. I am thinking the thermal mass would lower the consumption on average.
Very informative! Thanks for the video!😀👍
Suggestion to interested solar array / photovoltaic power seekers. When considering or setting up... consider going dc to dc when ever possible DC ACs DC fridge etc... DC powered appliances are available... going dc to dc will create an almost lossless system.
That's what an intentional community called Living Energy Farm in VA does-they power most things directly off the DC.
I have 400w in solar, with lithium phosphate batteries, the setup is very powerful for such a small array. Technology is really moving forward.
I was trying to get a 12v DC/24vDC refrigerator to avoid some of the losses by cutting out the converter but those things are surprisingly expensive for their size.
If you have the refrigerator already then you can get the compressor replaces to a 24V DC one. It is for sure the way to go if efficiency it what you aim for, the idle looses when using an inverter for a refrigerator is a bit on the high side.
Thanks, this was very easy to understand for me who has no clue about electrics.
Cheap inverters and cheap fridges have those horrendous efficiency ratings. It might cost you an extra thousand or two to get the energy efficient models but you will certainly get the money back in run time savings.(My 26 CUFT Whirlpool fridge uses what your little chest unit does!) It was expensive up front but has repaid itself many times now in running costs, even in Houston TX where electricity is cheap.
The Whirlpool pictured is VERY efficient (I have). It uses under 1.1Kwh per day. I had an RV fridge that consumed nearly 5Kwh/day. THAT was a drain on my 1500watts of solar. The Whirlpool effectively uses well UNDER 7% of my 15Kw battery capacity and allows me to run other systems. Now, mini-split still uses too much energy on COOL. DRY setting uses about half of COOL but I have to add electric fans to move the air around the RV. Having 2500watts or more of available solar would allow me to run the mini-split on COOL and replenish fully each day.
Great video on showing really how many solar cells and size of batteries to power such a small energy usage.
Running an inverter can certainly kill your battery. But if you run both the Fridge/freezer and the inverter off an Arduino, it can simply turn the inverter off and on as needed when the fridge/freezer hits a certain temp. An Arduino would cost much less power to run vs the inverter all day.
You may have a hard time to synchronize your Arduino (with a temperature sensor) with the refrigerators thermostat.
Properly better to use a refrigerator with no electronic and then let the refrigerators mechanical thermostat start/stop the inverter.
EcoFlow has an automation feature for scheduling the AC on/off that I am starting to use. I am going to do an off-grid irrigation project and see if this feature works well with and without connectivity.
@@K2teknik. I had thought of that also, but it would need to start the inverter first and shut it off last. So a dual thermostat set at slightly higher and lower triggering points might be necessary.
@@bafumat It all depend on the specifics on the inverter, can it start with a load? I would think that you can modify your fridges thermostats circuit to use it to start/stop the inverter and then feed the fridge from the inverter instead of the thermostat, but it all depend how/if the present circuit can be modified, fridge circuits can be tricky to put it mild. But this idea will bond your inverter to the fridge and that may not be what most people want. If you absolutely want solar to feed your fridge then replace the compressor with a 24V compressor and run directly from the batteries.
@@K2teknik. It would but if you're chasing battery life it's a step to consider.
I HAVE 4 DIY SOLAR GEN A 5000 WATT A 3000 WATT A 2500 WATT A 1000 WATT I RUN FULL TIME I LET THEM PAY FOR THEM SELF, HAVE GRID POWER IF CLOUDY DAYS COME WITH CHARGER ON THEM ALL PANELS ARE GROUND MONT ALL SO DIY BATTERYS NO BMS ONLY BATTERY BALANCER DOING GREAT , THANKS FOR ALL THE INFO
Just ordered the delta pro 3, looking forward to using it and maybe “saving” some money on our power bill
That is a pretty nice unit. Compared to the Delta Pro the increased solar is a very nice addition along with the 240V out capability 👍
What an informative video. Nice job, sir!
Thanks!
Overall, your presentation was excellent. The only difference I would do is stress a little more that over-sizing your solar is cheap, will compensate for slightly inadequate _expensive_ battery capacity, and will also make your _expensive_ batteries last longer by stressing them less. When over-sizing, I don't think doubling (especially for the smaller system) is too extreme; it also helps one get through cloudy weather.
Edit: Also, it seems you tested them in a garage, which is probably appropriate for the small guy, but not so much for one that's likely to live all its life inside. However, it tends to come out in the wash, because when it's hot in the summer and it runs more in a garage, you'll tend to get more than your yearly average solar insolation; similarly, when it has less solar in the winter, the garage-based one will probably run very little. Of course, all this is location-dependent, which is the main thing which should probably be stressed.
Thanks Scott. Being a complete novice at all this, I have a question. How do you get that a watt hour (wh) equals one day’s worth of power usage? I would think that something that consumes 100 watt hours would take 2400 watts in a day. What am I missing?
Yeah, that is a bit confusing. Here is the exact timestamp that addresses that specific question ruclips.net/video/IYjNv63CMS0/видео.htmlsi=A7Un90rpzXUB4K35&t=260
Hi @jacksonbooth2462 he was converting KWH to Watts 1000 x .23 and 1000 x .90. That through me for a loop to until I went back and noticed the meters were reading in KWH not Watts. Hope this helps
If something consumes 100W per hour, but only runs at that Wattage for 15 minutes, the total usage over the 24 hour period would be 1/4 of the 2400 Wh, or about 600Wh.
Awesome video. Thanks. Have you considered doing the same detailed vid on some of the newer 12V refrigerators, so that the inverters are taken out of the equation.
Think i will continue to plug in the wall, thanks
I have been load shedding my full sized fridge with my Delta pro since Oct 2023. It snows where I am. I did have to go back on grid about a dozen times. (just for the night while I was sleeping) This spring in 2024 I added more panel wattage and two extra batteries. The rest of my house has been consuming about 76 kWh's from the grid per month. Right now they owe me just under a grand Cad on my combined power and gas bill. My 9000 watts of diy with permits solar has been harvesting 10 MWh per year since 2015. I now have an off grid array for the load shedding. It's a fun hobby.
There are many things to consider ...like using a chest freezer or chest fridge which allows you to access goods without losing all that expensive cold air..start up current..ambient air temperature where the fridge freezer is located ..ventilation around fridge/freezer..a more direct use of electricity rather than into battery and out of battery...inefficiencies everywhere..
Best to use a chest freezer with a temperature controller from Johnson Control, if you need a freezer too buy a very small chest freezer to add to.
This setup is available in DC a chest fridge but it’s much cheaper to make your own. The only thing is it doesn’t work in the space your old fridge used to be.
Thermal insulate the fridge/freezer easily 50% more efficient.
If someone is using a victron Inverter, there is a standby setting it only draws a watt or so, and awakes in (user defined) interwalls to check for a load, if there is non, it falls back to standby. Its also possible to turn an Inverter off at night. Will save even more
Thanks.
Good video.
This still feels overwhelming mentally...
I enjoyed your video. I would like to see a calculation for the breakeven point for these battery systems. Thank you.
Thanks for the feedback!
Great info, thx! Then... in a worst case scenario being zero sun for three days, the fully charged batteries have ya covered. Day four the sun begins to shine, and now the solar panels are able to chill with zero battery. In that worst case scenario, don't I need extra solar panels that could simultaneously charge the depleted batteries to get me thru the next nite?
The biggest challenge a fridge faces isn't the amount of time it's open, it's the amount of time it has to spend cooling something down that's just been inserted. If you want a good stress test, take a bunch of water jugs at room temperature and stick them in the fridge at once. Then measure the amount of energy it consumes trying to get everything cooled down. If you just want an idea about how long you can go during a power failure, let the jugs cool to the fridge's temp first, then run it on batteries.
I find that having an RV-style chest freezer designed to run on DC is a handy thing to have around the house. It's built to be as efficient as possible and to also limit the inrush current it requires to spin up the compressor. It's also smart enough not to run the compressor at full speed when it doesn't need to cool a large mass down. Normally I run mine off just regular AC. But during power failures, I can keep it running for hours using relatively small power banks. And since it uses DC, there are no inverter losses.
the ON and OFF cycle also depends on ambient temperature and the fridge load. A fridge full of food has a better thermal inerthia than an empty fridge, and this leads to a lower power consumption, in case of a time limited power outage. Ventilation around the fridge also plays an important role in the calculation.
I don't understand how you used the NREL data to get this answer. The NREL value you found is 4.2 kW-hr/Day/m^2. 1.440 kW-hr/4.2 kWhr/m^2 leaves me with area but some how you got watts needed. I see that your values are for 3 days but I still don't see how you get your watts at the bottom of the table.
Thanks. Great video!
That threw me too, then I remembered that most people imply that solar energy is around 1KW per square meter. If you replace "KW" in the numerator with "M^2" (because they are 'the same', then the "square meter" terms cancel and you're left with "hours per day" which is what he implied in his calculation.
Glad you did this. Some folks have a really warped idea that solar is some kind of miracle. Case in point the 'Solar Ferry' which appears to have about 20-30kw of solar on it. Now this is a ferry that has to fight currents, carry people and cars and do it reliably every day, on the West coast. Obviously 20-30kw equates to max 30hp motor that the solar can actively drive. Now the municipality is screwed and had to buy back their old diesel ferry. I've seen the same thing on yachts, with selling points like 'Silent Operation'..... yeah if you park it and only run the fridge. I'm not knocking solar, but a whole lot of people don't realize that his is all calculable. Top it off with losses to charge batteries, peak power etc.. 25% losses on inverters are common with similar losses on battery charging.
Point is solar is really great, but it needs to be calculated properly and it really isn't that hard. Thanks again for making this great video showing some of the pitfalls.
I have a mini fridge with a separate door freezer section I'm going to try running on 200 watts of solar & one 100ah battery. Thanks for the info 😎
Running a conventional household fridge from solar isn't the wisest use of solar in general. The compressors aren't the most efficient. I do understand the premise of your video is keeping food cold or frozen during a power outage with pre-existing refrigeration.
I can contribute information based on portable 12/24 volt compressor fridges, as have been running such from small scale solar for the last 7 years in a 12 volt system in Australia. (Apologies in advance for using amps and Amphour ratings. This is how we calculated off grid solar up until the lithium entered with "watthour" ratings. I still prefer Amphour calculations).
Was able to power 2 x Endgel fridge/freezers totalling 140 litres in capacity. A 60 litre and an 80 litre, respectively.
The average daily sun was close to 8 hours with 5 peak hours in summer in Australia, obtained by keeping the panels pointed towards the sun.
Running both as a fridge, 2 x 160 watt solar panels and 4x175AH AGM(two batteries would have sufficed) powered these two without issue in 40 celcius heat. Average power usage per day was between 30 to 40 amps combined, dependant on overnight temperature. There was amble power to spare running as fridge's.
Running the 80 litre as a freezer instead, was a different story. It required two additional 160 watt solar panels for a total of 4 to maintain the batteries in that same 40 celcius day time heat(the nights rarely dropped below 25). The 80 litre Engel was set to minus 11, which is enough to maintain frozen foods(vegtables, sausages and kfc chicken) for the 2 to 3 weeks that it was in there. Meat was placed in the bottom.
During the heat of the day the 80 litre Engel as a freezer ran continuously to maintain the minus 11 in that 40 degree heat. The compressor did not begin cycling off until roughly 9 pm. It continued to cycle on for between 40 and 50 minutes out of every hour until the internal temperature stabilised
The power usage was around 70 to 80 amps per day. Hourly current draw was between 3.5 and 4.5 amps at 12 volts.
Winter is far less of an issue here in Australia. 2 x 160 watt panels can run both, using one as a freezer.
I obtained power usage data by using inline watt meters between each fridge and the battery bank. The watt meters were for 12/24/48 volt solar/battery systems.
The advantage of a portable fridge like the Engel(popular in Australia), Bushman, Evacool, Waeco(terrible company), Companion and many other brands of varying quality and price, is they can run direct from a battery bank without an invertor in between.
This system can be operated from a power station. That route is very costly compared to a diy solar batter system of similar capacity. The 4x175AH AGM cost 1000 bucks australian. Lifepo4 of comparable capacity at 12 volts, is 2000 buck australian.
Please note, 7 years ago, AGM batteries were the best in sealed lead acid batteries for off grid solar systems. Today, these batteries have been replaced with Lifepo4 in favour of their lighter weight.
For a 200 Wh fridge (15 minutes on) + 25Wh consuming inverter, and a 250W panel, you need one 24V 100Ah battery, if you have every day 10 hours sunlight. I have it running 6 months now and with 2 panels, I also can run my PC for 8 hours daily.
For the winter however you may need to double up 😅
In a long term power outage I'm going to "turn on" my grid tied inverters (with the main breaker OFF) and use the 24KW solar panel array to charge my delta 2 power plant and offset the power consumption of refrigeration. And in the winter I have a dual fuel generator that I can fire up to charge things up.
Hmmm, what type of setup do you have where you can use your grid-tied inverters when the power is off?
@@everydaysolar you need to consult an experienced electrician. I got a pure signwave inverter and 2 batteries along with loose solar panels to charge the batteries. Then with the main power breaker OFF I plug the 220vac inverter into the house 220vac plug. Then to get 110vac I have a step down voltage adapter. And use that to power refrigeration, tv, and solar generator when the sun is up.
The defrost is a heater.. so you can turn it on / off via external switch, or just manually defrost. You can also schedule defrost for noon when solar production is highest
I have a great way to keep my solar power exense to a minimum. I live in Alaska and we get very little light during the winter months (roughly October - March). I would need a massive amount of solar panels to satisfy the power needs of my freezer during the winter since it uses about 880 watts/day. So instead of buying a truck load of panels, I keep the freezer outside without power for most of the winter. On the few days when the temperature bumps up over 20 degrees I turn the power on to make sure everything stays frozen. I also freeze two 1-gallon milk jugs outside and put those jugs in my refrigerator to keep the refrigerator power cost down. I rotate the jugs every two days to make sure there is always a solid block of ice in the refrigerator. During summer we get lots of light and I only need a few panels to keep my LiFePO4 batteries at full charge. These little techniques don't eliminate my need for solar power entirely, but they cut the need and cost dramatically.
.... you must trust your neighbors and not have bear/rodent issues