I'm an older women who is fascinated with solar. I never trusted data sheets so I really appreciate your testing. Very clear and easy to understand. Thank you so much!
As one who working in the electronics industry as an engineer for over 40 years, I can assure you that a good deal of effort in both characterization and testing in performed on electronic components before they are released for use. For reputable companies like Enphase, Togo and SMA, the data sheet that you seem to dispute was developed not by some marketing guy, but by real engineers who sample a significant number of the product, collect and analyze the data under specified conditions and use statistic to summarize the results with MIN/MAX/TYP values. MIN and MAX values are +/- 3 sigma. You are at liberty to challenge the results produced in the datasheet but I would urge you to contact the manufacturer if you have an issue with the result or the test method used.
As an engineer that worked in Industrial automation industry utilizing inverters (VFD) in very hot environment like paper and steel mills I can assure you that electronic equipment is not happy being hot. I'll bet roof temperature in summer could easily get to 120 to 130 degrees. Personally I'll keep my extra cash in the bank and go with high quality string inverter.
Datasheets are the backbone of all electronic design and the key to maximising efficiency and safety. Without accurate data, it's all guesswork. So, the question you should be asking is "Do I trust the company producing the datasheet?" a lot of cheap imported stuff makes outrageous & unrealistic performance claims, often promoting hazardous use. The secret is to avoid Amazon products with no vowels in the name and stick with brands you know and trust, even if the cost is higher. Burning down your house can be very expensive and losing your life.. well.. nuff said..
There isn’t any inherent problem with datasheets, and it’s easy to spot the rare situation where one is inaccurate or even fraudulent. What the tests in this kind of video are achieving is *system level* performance results based on factors that affect the whole system, especially when it’s only 1 panel amongst an array that is somehow compromised. It’s no fault of the datasheet that system-level performance isn’t reflected in them.
The huge advantage of optimisers is that the DC power that comes down from the roof can go straight to a DC coupled battery and charge it with no conversion losses. This power is additional to the 10 kW limit of the inverter and thereby allows more than 10kW of power to be used by the house if the panels can provide more than 10 kW. As home DC car chargers are introduced EVs will be able to be charged and avoid two current conversion losses.
@@Mavisto2"dangerous" is all about how one manages risk: Clipping, shutoffs, shunts, etc... Unprofessional (whether individual OR "certified" contractor) installation = "Dangerous". Asking EVERY question in depth, even when one thinks one has them all covered is how "Dangerous" is removed from the equation. This is not new tech and the field of managing DC is very mature. It's only when someone decide to be willfully ignorant (ie: lazy about asking) or cut corners on necessary costs that risk becomes high and dangerous becomes real.
A very interseting test was done in Europe over a period of 1 year comparing a string inverter with both optimisers and and microinverters featuring real world typical shading (not heavy shading). The result was that there was so little advantage to either optimisers or micro inverters (like 2 or 3%) that you were better off just making up the difference with an extra panel or 2 which was more cost effective. In a heavily shaded scenario there may be a place for these technologies, but once again, they're expensive. A couple of issues with micro inverters : you lose flexibility that you might have with a DC system. ie - you could directly charge a home battery with a DC -DC coverter rather than going DC - AC - DC and if one des fail in the middle of a panel group it involves getting a technician on the roof, lifting panels and replacing the unit.
Yes I have read about that test and you are very right, with no much shade, its best to just remove possible points of failure all together. I also agree with lack of flexibility if using micros when it comes to future battery retrofit. \Thanks for sharing your thoughts and experience on this.
no high DC or arc faults - future proof if panels need to be replaced and that voltage panel is not around and panel level monitoring as your warranty insurance with black start and 25 year warranty available - enphase for the win
I'm still learning but doesn't the micro inverter setup give redundancy whereas the string system basically the whole system or at least one whole section goes off line if there is a problem? That's the big thing people keep mentioning when I look for comparisons between Enphase and Solar Edge, that the SE system can see whole sections of panels go offline when there is a problem, whereas enphase just one panel or even just one part of a panel?
Keep in mind that Enphase is also taking their AC reading AT THE SOLAR PANEL... whereas the Tigo / SMA reading for AC is at the SMA inverter, presumably a lot closer to the house utility panel... closer to the loads. Each leg of the Enphase is coming down at 120 volts vs 400+ volts DC for the Tigo/SMA system. So it's not inconsequential... could be another 4 or 5% less yield. Lastly, to get a real reading, you should be using a third party meter for both systems, at the point of connection to the loads. Maybe some CTs could do that.
Back in March 2020, I got 3 groups of 4 panels powered by APS microinveters with a small device that looks like a wifi router that reports the power output through wifi / internet. This small device didn’t cost USD 700, it was in the neighborhood of USD 150 if I recall correctly. It didn’t need a central unit, all microinverters were connected directly to my house’s power panel. Each microinverter takes care of 4 panels, so I bought 3, plus cables. I bought the whole system as a turnkey from a small firm led by a real electrical engineer. In comparison to a centralized system which he also quoted, without optimizer, there was a 20-25% difference. Based on the performance criteria, as it was an investment for 25 years, I went with the microinverters. I don’t know what the prices are at the moment (I’m not in US), but I guess adding an optimizer would decrease the difference, and still 2 issues to be addressed that you didn’t mention: electrical safety and future maintenance. Electrical safety: a centralized inverter with 12 panels in series would amount to 600V, before the AC output which is a hazard (in factories, 440V requires specialized technicians, individual protection equipment, etc), while the microinventers are dealing with 50V in parallel before the AC output, and the 3 inverters are independent from each other. Maintenance: although panels have 25 year warranty, the inventers probably have 5 years (perhaps 10 in some cases). If a centralized inverter goes down after the warranty ends, you have to pay 100% of the system price to replace it, and during that time you get 0% power from the solar panels. In comparison, with microinventers, if one goes down, in my case I will pay 33% to replace it, and still will have 66% of the power. Those are important aspects to consider. My system will have paid back itself sometime this year, I’m paying minimun consuption for my electricity provider, with still 2000 kwh in credit. Water heating included, I moved from gas to electrical. Last point, scalability: I added 4 more panels last year with same type of microinverter, no changes in installation besides adding the new group to the app control. I don’t know how it works to add panels with a centralized system. I did this because I got an EV as a company car, and now I save also on fuel. Best investment in my life, no taxes for the savings (I pay less tax now I my utilities are reduced), and continuous cash flow that will help a lot when I retire.
That’s a good point. I don’t know about every sting inverter, but the two that I have seen have multiple input strings where voltage isn’t allowed over 440V. On my own SolarEdge system, the optimizers (regardless of how many on a string) adjust so that operating voltage is 400V.
@@imnguyen6658 battery system not affordable here. Perhaps in the future. It would cost multiple times what I paid for the system itself. No business case currently
Great video and terrific testing, your customers are very blessed to have an awesome business owner that actually has tested the systems and can recommend the best solution for their needs, keep up the great work you are doing
You completely missed the fact the the warranty on the sunny boy SMA inverter is 10 years and will need to be replaced after about 10 years for additional cost. The warranty on the enphase inverters is 25 years and will last the life of the system without needing to be replaced. This would add an additional $5,000.00 (replacing the inverter twice) to the TIGO / SMA system over the solar panel warranty life of the system. I designed photovoltaic systems for 3 years for SolarWorld to include hundreds of residential and commercial systems from 3,500 W to a 1.5 megawatt system for an airport in the Dominican Republic.
May not be reliable info, but I was listening to a paid program by Solar someone. SMA was matching Enphase warranty. I think your comments are valid. 😅
My neighbour is at is 3th inventor in 16 years. The full production was off for one week x 3. If this happens with a micro , you will only loose one panel.
Another great video! It would be important to include a failure rate analysis of both products. This is a big factor for most installers. I worked for Fronius and now work as an Application Engineer for Enphase. At Fronius, we paired the inverter with a Tigo optimizer, and the feedback from installers said the failure rate was higher than other products they installed. Working at Enphase, I don't really hear about any major issues. Once in a blue moon, I do hear that a surge from the grid can cause the microinverters to fail. I would like to get your feedback. I love your videos, keep them coming.
Thank you for sharing! Yes I definitely want to do a video on failure points. It would be interesting to see, especially with Hoymiles making a big entrance.... :D I would go Enphase over any micro anyday, but personally I am more of a string inverter type a gal :D Thank you for sharing your history in Solar
To me the value of Enphase isn’t a slightly better or worse production. It has to do with no single point of failure and proven reliability no other inverter option can touch. Great video!!!!
@@macmierzwa5361 the 5 year warranty is because of the envoy potentially having compatibility issues in the future and Enphase not wanting to be on the hook to create a whole new component to communicate with future wifi or cell signals we currently don’t use. The other aspect is simply the combiner box which you can use a generic sub panel instead if you’d like. When the was the last time a normal electrical panel failed on your watch? I’ve literally never seen an Enphase combiner fail in 7 years
As long as a micro-inverter in the centre of an array doesn't fail and you have to remove many panels to get to the dead inverter. It happened to our neighbour. Absolutely dead unlucky, but it goes to show that whatever can go wrong, will go wrong, with the most inconvenience possible...
Had Enphase inverters installed in 2014. Currently running with 5 dead inverters. Even though Enphase will warranty the inverters, the cost of removing my panel array to identify which ones have failed is simply not worth it. I had 3 systems installed at the same time, 28 panel systems, on 3 different houses. All 3 systems have experienced similar issues. I was gun-ho on Enphase in the beginning, not so much now.
Thanks for all the effort you are putting into your videos to make it digestible. These tests could be boring but you make it very entertaining! Thanks again Martyna.
I am so happy you said that. Thank you so very much for the kind words. I was honestly worried they will be so boring. Next time maybe add a joke here or there or funny facts or sth. :)
Fantastic video. My system was installed in 2016. There was no such comparison video back in 2016 when I was choosing between Tigo and Enphase. I ended up choosing Tigo and, seeing the results of the video now, I think I made the right choice. I currently own stocks in both companies.
The thing that strikes me as weird, is the changing relative outputs between the two test setups (considering only the unshaded panels). And the changing efficiency of the string inverter. At first I thought it might be temperature. That is, as the optimizers warm up they produce less, but later they were back to beating the microinverters. And at one point the string inverter was 95% efficient, and the very next test it dropped to 84%, but later bounced back to 93%. I wondered what sort of load you used, and concluded the simplest and most accurate would be to simply dump all your power to the grid. It doesn't matter if you're dumping 1KW or 3KW (per test setup), the grid voltage should hardly change. So it really comes down to how much the inverter (micro or string) _wants_ to dump onto the grid. Which is a little like an MPPT circuit hunting for the optimal mix of voltage and current to maximize output power of the panel. In the inverter''s case, they might output 239 VAC, 240 VAC, or 241 VAC, and that 0.4% change in target voltage can make a much bigger difference in output current (maybe as much as 5%), which could totally account for the ping-pong performance difference between the two test setups. So perhaps the overall power output difference (because it's so close) is irrelevant. The interesting result is the effect of shading panels on both systems, which also seems close enough to be largely irrelevant. The conclusion I come to is, buy which ever one you want. They're both good.
Hey Scotty, so true and I was also very suprised by the change in the DC to AC conversion. I so wish we could see the DC input of the microinverters, and compare to the AC output. Most major inverters whether string or micro, are similar in the efficiency so its very interesting to see those difference. Just like you concluded, at the end of the day, the homeowner has to decide, since they are both very good! :) Thanks so much for leaving a comment!!! :)
It would be nice to also have seen a full day of non-shaded production. I get the feeling the micro inverter may have performed at least 10% better over the course of the entire day. But i think you are right in your summary in that it really depends on your situation and needs.
Finally, REAL shade testing! (Like from a nearby tree, chimney, or building, etc.) that STILL allows indirect sky light to reach the shaded cells. Guessing this is a first on all of youtube... Well done.\
@@robertsmith2956EEVblog’s shading issue was without optimizers. That’s exactly the problem optimizers try to solve - and judging by the results in this video, it seems to do it very well
We have 48x400 W panels on our roof. Feeding into a Sol-Ark 15kW unit. We have not gone with any optimizers since the panels are mostly on the second story roof and unshaded by trees. That being said, one string of eight is often shaded by a chimney stack, blocking its production for much of the day. It may be better to move a portion of those panels to the adjacent rough surface to eliminate the chimney shading. That being said, we still produce over 15 KW when the sun is mostly overhead. Enough to meet our needs by far. I think one also has to look at the additional failure points by adding an optimizer to each panel. Pros and cons. Good video.
Hey! Thank you for sharing your system set up, and yeah you are very right, avoiding those extra points of failure is a good way to go. If you are happy with your system output, that's what matters. anyone can always say:" It COULD be better. BUT its great as is and you're happy with it. :) I love Sol-Arks!
Excellent comparison video. Easy enough to understand. As an electrical engineer, I REALLY appreciate real world testing. This is first time I've seen any comparison video for solar panels. While I would have loved to see better numerical comparison when comparing AC to DC output for individual panels versus an entire set of panels, the point is not difficult to glean. If you haven't already planned it, I'd love to see the same comparison for batteries; that would be awesome!
Check out neo Volta. I had the 24K installed and it runs my whole house except for the central AC which I keep on the grid because it sucks too much electricity anyway. But I installed 110 volt mini split if there ever was an outage on the grid.
Love your experiments and am looking forward to the other testing mentioned in your replies. I've DIY installed two 4.5k systems on my south facing roof with minor shading. One system is a SolarEdge 3800 and the other is Enphase IQ8m's. Surprised that the Solar Edge has consistently out performed Enphase day in and day out by a solid 5%. It will be interesting to see how your test goes.
Oh wow! Thank you so much for sharing! This is very interesting! What type of panels did you use if you don’t mind me asking? The great thing is that this truly depends on so many factors! Thank you again for sharing!
The SolarEdge install has (14) Canadian Solar cs1k325's. It's almost 5 years old . The Enphase install uses (8) rec365aa's and (4) rec395aa's, it's not quite 2 years old. To tell you the truth, the reason I have this setup is that I was in the process of completely converting to Enphase, but with the performance issue with Enphase I've decided to go a different direction. I'll be adding whole house battery backup and V2H EV charging in the next year or so and right now I'm leaning towards a Sol-Ark 15 with their new optimizers - we'll see.@@solartimeusa
Really nice video, but you didn’t finish the cost vs net gain…if Enphase gives you 3% more - these “savings” offset the extra cost and your pay back time alters? Keep the trials going nice to see real world examples rather than the usual marketing blurb…..
Power is not the only benefit from microinverters. Redundancy and expandability are other major, major, advantages of microinverters. Also, reparability, guarantee term, ease of troubleshooting are other things to consider. Microinverters are a solar game-changer.
Thank you for this brilliant experiment. I have Enphase and I’m happy with the microinverters, but the cost was more. Would be great to see how the iq8+ compares to the iq8a on the 400w panels
@@solartimeusa This was 3 months ago and still no test between the iq8+ and iq8a. I don't know the difference but I think that the plus can be used with more powerful panels.
@solartimeusa I'm doing research on Solar, and I found that you made one of the best videos on it. No one did this much deep analysis on RUclips. Please keep it continuous 💐
I thought you did a wonderful job! I was also pleasantly surprised that you compared the cost of both systems in the end as well. It appears that the greater efficiency of EnPhase won't recoup the extra cost over the life of the system.
I was surprised the shading test are not comparable with cloud cover. It appears the Tigo system does better in low light. The cloud cover you mentioned was very small. I would be interested in a test conducted across different cloud cover conditions. That will take time to collect for sunny -> heavy cloud cover.
Thank you for the testing. Most of my experience is with solar panels on conversion vans so relatively smaller systems. I didn't realize that optimizers could help so much with shading challenges
Your test solidified my choice for SolarEdge Power Optimizers and the string inverter. The difference in cost compared to my neighbors who went with Enphase and micro-inverters is so drastically different I try not to tell them my actual cost....
One more aspect to discuss and possibly test is the power loss difference between DC and AC power running along possibly long wires, from one side of the roof to the (SMA or SolarEdge) String Inverter (for DC) or the IQ Combiner box (for AC). Why understanding is that running DC power along 50-100 feet of wire might incur sugnificent power losses, which is not the case with AC power, which makes the conversion from DC to AC closer to the module a better choice. What are your thoughts about that? This field test didn't really test that, since all the wires are very short, which will not be the case in real-life applications, when the panels are spread along the roof area(s) running long wires from the Tigo (or SolarEdge) Power-Optimizers and Enphase Micro-Inverters.
Thank you Martyna for describing by conducting different tests and arriving at concrete results to decide which may work best in a given situation. I will watch this clip again and again and highly recommend to individual(s) who may have doubts in their heads on deciding which system to go for....By the way that athletic flip was hilarious.
Great video and the testing was very intensive. I have the Solar Edge optimizers installed just a couple of days as I realised later but I think overall with a power production guarantee for 25 years from almost every solar company, it may not be a big difference.
I will be testing SolarEdge against Microinverters soon, but you are correct! The difference is so small, I really don't think you should regret anything, and especially if shading is not even an issue. You should feel good! I like customer service with SolarEdge, they make it really easy to replace faulty units, and are pretty quick about it too!
Hey Martyna, you're a natural in front of the camera, I really like these tests, and I don't think you can beat a basic string inverter without optimisers for simplicity, you may lose a tiny bit of production, but for me the less electronics up there the better. PS You can do cartwheels any time you like LOL !!!
Hey Andy, Thank you so much for leaving a comment, I really really appreciate any support! And I am 100% on the same page as you as far as the string inverter goes! :)
Good video! Test 11 is more relevant than the other tests which used leaves and cardboard. In real life, panels never see full shading that the cardboard presents, diffused shading from chimneys, vent pipes, trees, and structures is what we actually experience.
I was the first installer in Arizona to use SolarEdge. Split my 24 panel array of Trina 230's in half and put SolarEdge on one half and the old Zantrex string inverter on the other half. Virtually no shade. Guess what? Zantrex won by a smidge every day. Since then, half the SolarEdges I installed have failed. Would you rather have an ultra reliable array running on a string inverter where you can't see the individual panel results, or would you rather have a much less reliable optimized array that you can easily see the failures?
I am solar permit designer in india and I appreciate your test it is eye Operner for me because I thought there are significant energy dropped in inverter system if there Shadow shade on pv system but there no much different. But in term of costing it is worth. And keep working and testing for ❤(inverter) of solar system. Thank you
Great experiments. Thanks! My understanding is Microinverters have a 25 year warrenty, and regular string inverters a 10 year warrenty. Figuring in the need to have to replace the string inverter at least once or twice over the 25 year warrenty on most solar panels (plus installation of it), and the roughly 3% more production of microinverters, the microinverters seem the most long term cost effective solution.
As a avid tenter the most important is battery tech so or more videos you test between using different battery tech to see what is the best/and cheapest batteries to use in their systems!
It also depends on the quality and tech of the panel and the comparability of the brand inverter. Some panels just go better with certain brand inverters and some clash. As a generalisation premium panels with good micros will outperform a string inverter system with optimisers.
Lots of efforts to put together two solar inverter systems and carry on the experiments. Thank you for making this comparison video. Also conclusion is also very clear. If during a day shadows come and go on the solar panels, go with micro inverters. If there are no shadow issues, go with one central one inverter and save some money on the equipment. Also get more power in caparison, since no shadow issues.
A brilliant test and great, very clear video with clear easy to understand graphics, thank you! I have an East/West roof and will fit panels in each direction but a sizeable chimney in the middle to one side (Victorian house) so will have varying amounts of shading over different panels throughout the day! Very interesting!
Thanks, that was really useful. I wish to point out one small mistake in the costs ( @ 20:49), the IQ8A @$233 plus a Q cable @ $18 = $251, not the $241 which you have shown. Therefore the Enphase system is even more expensive by $250, but that is small compared to the total system cost which is $7008.
Great video. Would love to see the same test using SolarEdge. SolarEdge is what most EPCs are using along with Enphase. As well, it would be great to see the output by Enphase after conversion from the AC on the roof back to DC into a battery, and then AC into the house as mentioned in other comments.
great points and i have the solaredge inverter prepared to test it, just need to find time!!! :D I agree that would be great to see too. I mayb start asking those companies to send me their batteries to test, because its getting expensive haha!
A very interesting comparison, thank you. It is worth noting that the Enphase system does not have a single point of failure. A dead Enphase inverter will stop production for one panel while a dead optimiser or central inverter will take down the whole system. A comparison of cabling cost from the roof the central inverter/combiner box would be interesting. AC cabling is mass produced while high voltage DC cabling is more specialised. It would be interesting to compare the AC power reported by the systems with a 3rd party meter.
Great video! I had no idea about solar in 2015! I got a system with SMA Tripower AND TIGO Optimizers MM-2ES75 for ALL modules. I am so happy since 2015 - NOR the SMA - NOR any Tigo had any fault till current time and contine to work geat!
Hi, thank you for another great video. I like very much your approach and at min 19:49 you show that Enphase has produce 3 to 3.5% energy. What is also interesting to take into account is when you have battery storage. Enphase will have more current conversion than if you have a DC coupled with Tigo. At the end it would be interesting to see what you get out of your batteries.
This is exactly what I am wondering. Especially for an off grid system that is mostly DC anyway, avoiding those conversion loss's is a big thing. The one time I see the micro inverters as a plus is a grid tie system that does not have battery storage. From all of the research I have done, any system with battery storage in it is better off with optimizers over micro inverters. DC-DC charging efficiency is almost always higher than AC-DC. With solar getting more "common" I hope to see more DC appliance options. There are already DC refrigerators/freezers available, as well as ceiling fans. POE systems are ripe for running off of a 48V solar battery system. That can currently cover lighting, some TV's, a lot of security systems, as well as ports for all sorts of usb devices. Large loads are really the only problem area right now for taking a house completely DC. I am also very interested in building sciences, and believe we have the technology, RIGHT NOW, to be fully capable of building houses that are self sufficient from an energy standpoint, at a reasonable cost compared to current minimum code compliant standards. The biggest problem is convincing people to NOT do the same old thing, but instead do it better.
Excellent video, very informative and real comparation side by side. I know you took the avg price based on manufacturer, but IQ8+ can be found for little less than $200 each, and sometimes $150 each which bring the whole system down to $4.5k I still prefer Enphase, I did a 8 panel installation in South America (where my family lives) and is the best solution, because I can expand the system very easy, and if one microinverter fails, is easier (in my case) to replace it vs the string inverter, besides only one panel will go down instead of the whole system. Another advantage is less cables and only 220~240v max, while with an string inverter, it require DC protections and higher voltage per drop, but the later is a better option if you need a battery backup system.
Great testing, it's likely the most truthfull in the industry keep up with the good work. I have a strong belief in no shading for a roof and a simple layout string inverter all the way. If the roof is chopped up or shaded micro is worth it, and we use AP systems. Finally if it is a ground mounted we only use bifacial panels with string inverters and no MLPE at all.
Hi Martyna, love your videos! Thank you so much for conducting such great real life & head to head experiments. Two questions: 1) it seemed like you had pretty significant DC to AC conversion losses on the Tigo/SMA side (10%?). Is that typical or were your AC CT readings a little off? 2) Enphase used to have a lot of reliability issues (compared to Solar Edge for example). But then Solar Edge seemed to have A LOT of problems with their HD series inverters. Comments/thoughts on equipment reliability (as an installer) in 2023? Lots of innovation on the Enphase side. Of course it’s not cheap. Thanks again! Jonathan 12.2kW Panasonic / 11.2kW SolarEdge installed in 1997.
Hey!!! Yes so next test will be Enphase Against SolarEdge. I was personally a bit surprised too at the losses from the conversions. Too bad we can see the DC input on the micros, along with the AC output. That would be interesting to see considering most inverters vether string or micro have similar efficiency ratings. As far as reliability with ENphase, I got burnt years ago, so I am not too trusting of any microinverter, but to be frank, I have not experience a whole lot of replacements in the past 2-3 years, so they must have improved something! :) SolarEdge seems to have a bit more issues, but they ALWAYS replace faulty units and even provide labor reimbursement, which Enphase does not have. I have had a lot of homeowners who bought a home with a pre-existing system, that was SolarEdge, and with no problem they transferred the product ownership to the new homeowner, and all warranty replacements went pretty smooth. So there are pros and cons to both...:) As far as my preference.... I have to be super honest here. String inverter any day.... :( I am very trusting of SMA, even though they aren't as popular... they are made in Germany, and myself growing up in EU, I trust the quality of those products way more than anything made elsewhere. But that could be my Polish-ness talking. Thanks again for sharing your thoughts here, I so appreciate it! Martyna
@@solartimeusa This is a very time consuming test and thanks for doing all that. I was wondering if you can redo only a small subset of the test with Tigo + Fronius inverter, the reason I am asking is that their global maximum point tracking system algorithm is different and in some complicated shade scenarios might produce a different result. Would love to see this but I understand this takes a lot of time and energy to do so.
I have Tigo and SMA and I can confirm that depending on weather conditions you will have around a 5-10% loss in the conversion. You will have less loss on sunny days. For instance I had a day with 98 kwh produced DC and 94 kwh AC. On the cloudy day i had 7.4 kwh DC and 6.6 kwh AC. I don't think her test accounted for the AC losses on the Enphase system as her results were from the micro-inverters not any down line CT's like the optimizers.
Thanks for the informative video. My first thought was to say that a great deal of difference would be seen if you have to place your panel array further from your house. For the string system you would either have to run expensive wire to carry the DC to the house inverter or you would suffer loss. The Microinverters would be much less susceptible to loss since AC can travel further on thinner wire without as much loss (which is why our grid is AC). Your testing of both arrays being adjacent to your building eliminated this from the equation. In my case the array will be about 100 feet from the house.
Thx a lot for testing the architecture of the panels by shading them. As one can see the diodes are working as intended. Simple question: what's going to fail most likely, the panel or the electronics? Hence, simple rule, do not build an electronic box per panel on the roof!
A thorough, informative video, thank-you Martyna.. Reading about the effects of partially obscuring panels and the effect this has on the different inverter configurations is interesting, academically, but seeing it done helps cement the ideas at play. Plus, your cartwheel was an unexpected little treat.. Keep up the good work..
Thank you so much for leaving your thoughts and sharing. I am sure I could have done this test in different ways or speak about it differently but I hope its a step into the right direction for good product testing. :)
Thank you so much for leaving your thoughts and sharing. I am sure I could have done this test in different ways or speak about it differently but I hope its a step into the right direction for good product testing. :)
It looks like neither system is a clear winner nor loser. It depends how much shadow can fall on your panels. De difference in installation costs is huge. But if you live in a place with many clouds, trees, buildings etc, over time the cheaper optimizer system might be more expensive. But if you add one or two more panels, it wouldn't make such a difference in initial costs and they could catch up with current lost in shady times. I'm still learning and try to understand, before i decide to start with a system. Thanks for this video, it helped a lot.
What I believe is the most convincing result that you have presented is the substantial cost difference between the two. The other factor to consider is reliability of the two systems. The Enphase unit is really an optimizer (to do maxim power point tracking (MPPT)) and the DC to AC inverter all in one package. Enphase has to put the inverter section up on the hot roof were as the string system the inverter is usually located in a cooler area. Temperature is very import factor when it comes to reliability and the life of components. One of the most temperature sensitive components in electronics are electrolytic capacitors. The inverter section needs electrolytic's to to do filtering of the DC since the AC power is changing from 0 power at the AC zero crossing going all the way up to approximately 1.4 times the power output when it is at the peak power output. This happens 120 times a second for 60 Hertz USA power and 100 times a second for 50 Hertz European power. I once opened up a failed string optimizer and found no electrolytic capacitors located in it. They are located in the inverter. I never open up an Enphase but I believe they have electrolytic's' for the DC filtering. Even so the higher roof temperature still would negatively affect the reliability and life span for all the components which includes for the Enphase the inverter section. Also in the Enphase system the inverter has to be duplicated for each panel this results in not only in a higher cost but due to the higher component count it will effect reliability as well. The string inverter would have approximately the same component count as just one of the Enphase inverter section. In the string inverter the components would only need be larger due to the higher power output requirement. Many installers like the Enphase because I was told in the beginning they offered the installers a generous warranty payment when a failure occurred. I don't know if this is still the case but they more than likely they now stick to what they know. By the way I thought the cart wheel was impressive. :-)
And adding a suggestion: you should test one shading condition at time. The way you did you'll always have a dominant condition that will have the biggest impact. As we cannot compare directly DC vs AC, it's hard to understand the final AC output result.
The biggest difference is a micro inverter system does not have a single point of failure, like a Solaredge optimizer system does that feeds into a single string inverter that can fail and shut down the whole system
Great video, fantastic comprehensive test. The fact, that covering 1/3 of a panel is as bad as covering half of the panel, comes from the construction of these - usually these are divided into two sections and such covering disables one of them completely. What is more interesting - the power output from panels that are not shaded (let's say #2): - 5:37 - microinverters 159W, string 186W - 7:34 - microinverters 222W, string 244W - 12:15 - microinverters 314W, string 302W - 14:09 - microinverters 326W, string 332W How can we explain this? Does increasing heat affect the optimizers more than microinverters? Also, something very interesting happened at 16:07 - panel #3 without any shadow on microinverter gets 328W, while the one with optimizer only 240, identical to that one with "chimney". Why is that so, especially when at 17:20 it does not lose the power? BTW, was the string inverter in optimal, chilled place? Nevertheless, it is more important how this lasts throughout the years. Microinverters are exposed to extreme weather conditions (heat, cold, water) and this might shorten their lifespan. On the other hand, string inverter works with much higher voltage and wattage, which might also cause failures. But summarizing - the actual differences were really small, and what is important - if you know precisely your lighting conditions, you may install optimizers only on selected panels, reducing your cost even more. However, having optimizers may help with identifying any problems with some panels - without them, you just don't know why your whole string performs worse than expected. And still cost of microinverters is so high, that won't pay off ever. And installing PV is all about money, so... 😉 So to sum it all up: IT DEPENDS 🤣
One consideration for some may be that micro inverters are subject to EMP destruction (whether natural or anthropogenic) while the all DC PV PNL systems are robust with respect to EMP. Centralized AC inversion within the building structure may of course be remotely shielded. The case for AC of course is made where long cable runs from the PV PNL’s are required where DC I squared R losses become significant. Philosophically I favor maximizing DC thru out the house both for DC reliability and electrical efficiency. This is why Auto, Marine, Aircraft, and electronics utilize predominantly DC. Where AC is required over distance and for AC appliances one must accept the inefficiency of conversion. With AC comes both efficiency losses of conversion and parasitic losses of maintaining inverters operating in standby w/o being loaded. These losses in turn must be alleviated with more PV PNL’s and larger batteries. Martyna, Thanks for empirical testing instead of biased sales pitches. 👍t
Be sure to also consider access - micro inverters under every panel may be impossible to access to replace one when it fails in the center of the array without removing many other panels to get to the faulty one.
Very interesting. I guess there is a crossover point where the Enphase may be cheaper, since you have a big central box in the string inverter case. I'm not a fan of optimizers because of the added complexity and cost, but microinverters add to the benefits of optimizers by removing the amount of hvdc cables routed around the house, and they have excellent warranty too.
Very nice Video! When it comes to safety Micro-inverters may be better as the TIGO's always let the high DC Voltage thru. There are however "Huawei" and "Solaredge" Optimizers that don't output Voltage unless the Inverter is active! With the TIGO's I would only put them on the panels which are expected to be shaded. (trees, chimneys and overhead power lines etc...)
Thank you for the video. It was very enlightening. On the sad note: this is such a bad morning / low light result for Enphase. I bet, Enphase on a cloudy or low light winter day will half your output. It needs more power to do a better conversion to AC, this is why early in the morning in your test, it was 40%-45% less then Tigo (raw power), but by noon they almost leveled off with no shading. In addition to this you will lose another 10%-15% again if you have a 48V battery backup system to charge with Enphase system.
@@solartimeusa Yeah right? I was wondering if optimizers would perform ok with mixed roof orientations, or if it is better to go with microinverters all the way. 🤔
What do I think? I'm a Brit and your description of a "cloudy" sky is our version of a bright sunny summers day.😂 Secondly the amount of panels you guys can fit on your roofs is probably almost three times more than a lot of houses here.😂 Joking aside, thanks for a brilliant experiment it really helped explain the actual differences between micro-inverters and optimisers rather than the technical ones. After all what is most important to a home owner, how efficient it makes your panels or how they work and why they do what yhey do? Simply how efficient they make the panels in comparison to how much they cost is what we need to know.
Nice comparison, I live in Estonia and get completely different results and the Microinverters are working only from April to September. You should repeat this test in Ohio in a winter month and you get complete different real life results
Would be interesting to see a similar test performed using a different set of solar panels - panels that utilize a 'shingled' style interconnection of cells (effectively a series string of parallel-connectef cells). Would expect to see outputs in more direct proportion to the percentage of panel shaded. Additionally, it would be more realistic, I think, to use a shadow generation technique that still allows indirect illumination of the shaded portion of the panel since that more closely mimics typical shading VS applying an opaque 'shade generating' shape directly to the panel surface.
Just a question at 9:21 Tigo was making 2095w DC and normally the conversion to AC was less than 100w however this time at 9:26 SMA shows 1765w why the major reduction from DC to AC? Again just a question why the conversation not remain within 100w from DC to AC? Is the unit getting hot or something?
Also at 20:43 the math seems wrong 233+18=251 not 241 so thats 6,275 .. also the price difference would be even grater if you used an EG4 6000XP inverter for $1.3k vs a Sunny Boy for $2.4k just saying, however i get the point.
Great video, with the outcome that the micro inverter technology is incrementally more efficient while solar energy is being generated. What the efficiency variance between the technologies factoring in solar battery charging and pulling the power out for AC use when solar power is not being generated.
I have a lot of intermittent shade and multiple small roofs so determined I would be better off with microinverters. After two years, they have worked as expected and I have no regrets. Obviously if I add a battery I will need an AC coupled battery so the extra AC/DC conversion losses may be an issue. I did a TCO cost over 10 years and for a 10kW system the microinverters cost about 10% more overall, but on a cost/kwh of generation for me the microinverters were 20% cheaper than a multi string DC inverter setup. Also, reliability of the microinverters is anecdotally better than DC boosters. TBH, either system will pay for itself completely in under 6 years so ideciding which solar to get is less important than deciding to just get solar.
Bad math. Your calculations should be as follows: 233 + 18 = 251 251 * 25 = 6,275 +733 = $7,008 vs $4,116 What were the make & model of the solar panels that you used in your experiment? I'm curious to know how much actual wattage you monitored vs the STC wattage of the panels. Well done video, by the way. That was a well thought out & well executed video! Ty!
@@solartimeusa Those are pretty high grade panels. I'm a bit surprised that you only got 328W max from a 400W panel under full sunlight conditions (yes I'm aware that you experienced partly cloudy conditions akso, but there were definitely fully sunny conditions too.) 328/400=82% of the STC. Even if the day was very hot, the % loss from high temps would likely be less than 3% of the STC rating. If you measured a higher peak wattage than you showed in the vid, what was the max for those panels?
Thanks for the video - great testing. I do have a couple comments, though. It looks like there may have been some shading that wasn't yours. In the morning the values on the unshaded panels tended to be higher on the Tigo side and in the afternoon they were higher on the enphase side. That seemed to impact your numbers. The panel next to the panel with the small chimney shadow was lower when you were testing, which you noted, but this indicated a shadow from another source (like a cloud), because in the next test, that same panel next to the small chimney shaded panel was back to the value for the unshaded panels. Obviously this is hard to control for, but it just means these tests are approximate at best. Again, though, I do think this is great info.
Thank you for this. I'm debating between a Victron 1200-watt Inverter or microcontrollers. At the 1200-watt system size, the cost is exactly the same. I think I will go with the Victron only for a better-quality product even though it means running DC cables longer than if I ran microrcontrollers at each panel. Of course, it will also mean I won't have microcontrollers out in the sun/heat.
Great video. Would love to have a searchable title such as Tigo vs. Enphase, or something to make it easier to find based on your other video. Was looking for this for a long time.
Great real world comparison test, would have been good to have compared against panels on a simple string inverter with no microinverters or optimizers.
one extra problem you might wish to consider, is the failure of an inverter, on one Tigo/Sunny boy it knocks out the whole system (stops power generation until fixed and costs a lot to replace, on the enphase system. The loss of just one microinverter is only going to drop 4% on a 25-panel system and isn't hugely expensive to replace and it also does not knock power generation ..this makes the enphase systems huge amount more attractive cost-wise
Can you test SMA and Fronius string inverter on same panel set???? That would be cool test to show difference in shadowing controll in string and how MPPT controlls voltage and current!! Nobody has done that!! 8 or 10 perc panels (410w), there is difference in line voltagecontroll in mppt. Depence who has make the string inverter
Another video full of hard data, very well done. The only point I would make is that the cardboard was 1/2 and 1/4, no where near 1/2 and 1/3. Doesn’t really matter as the testing was well done for both systems.
Enphase is 8 MPPTs vs 1 MPPT string of the Tigo system. With extreme shading conditions Enphase has the output advantage due to multiple conversion points. They stay in upper 90% efficiency range. While the SMA inverter shows efficiency loss when not at peak output with a single MPPT string. Notice the SMA inverter out performing the Enphase when the solar input was higher in the morning tests. The only way to prove which is better is use an entire day production of kwh not just specific points of output. Run an 8-10 hour output test. John 9.25 kwp with SMA SunnyBoy 7.7 DIY installed 2020 without optimizers
Hey! Yes, I do want to test more realistic conditions. Not applying direct shade but maybe place a "tree like" shadow on both arrays and let it run for multiple days, preferably one full clear sun sky, one with some clouds, and one rainy day. Definitely want to do that to see how different the results would be. Overall you are very right, rather than comparing individual outputs, looking at total production we get, would also make it easier for homeowners to understand.
The SMA / Tigo system is cheaper but they don’t offer 25 year warranty as Enphase. During that time you will have to replace the string inverter of SMA and maybe some optimizers and after that it becomes the more expensive system in addition to being more tedious. Also it will not produce electricity during replacement time. If one Enphase micro brakes down the system will continue to produce electricity.
@@macmierzwa5361 It’s the string inverter that will fail long before 20 years whether it’s an SMA, Solaredge, Fronius etc. In real life however, it has most likely had to be changed for a bigger string inverter after 10 years when adding some more panels. Something, which is not required with microinverters.
I'm not 100% sure but it's most likely that the optimizer modules have built-in bypass diodes. If the main circuitry fails the rest of the string will still function.
@@eDoc2020 I think you are right. If one optimizer fails you will be fine (whole system is not down). It’s the string inverter that is the bottle neck / risk point.
In both cases the power reported is from the manufacturer's systems. I wonder whether that would match up with measurements taken by CT clamps near the consumer unit. They both have a vested interest in reporting a bigger number. My biggest worry is reliability. My roof is very hard to access, needs scaffolding etc (not just a scaffold tower). So a single failure might cost $$$ to resolve, simply due to having to access the device.
The one variable that I believe you should have included in your test is the inverter efficiency This has a profound impact in the total wattage produced especially for people that install battery storage on their systems bc with micro inverters, you lose more power as the power is converted from dc to ac (loses), then it’s converted back to dc at the storage point (loses), then at conversion back to ac (more loses) whereas with optimizers, the lose is only at conversion from dc to ac for usage So I believe at the end, optimizers will carry the day
Best solar videos on RUclips. I love these experiments so much
Awww! That makes me so motivated to keep doing those tests. Truly, I appreciate the comment!
Indeed hands on results
I'd like to see this same test but how much battery is charged to a battery backup
I'm an older women who is fascinated with solar. I never trusted data sheets so I really appreciate your testing. Very clear and easy to understand. Thank you so much!
Thank you so much for watching and leaving a comment. I really appreciate it!
As one who working in the electronics industry as an engineer for over 40 years, I can assure you that a good deal of effort in both characterization and testing in performed on electronic components before they are released for use.
For reputable companies like Enphase, Togo and SMA, the data sheet that you seem to dispute was developed not by some marketing guy, but by real engineers who sample a significant number of the product, collect and analyze the data under specified conditions and use statistic to summarize the results with MIN/MAX/TYP values. MIN and MAX values are +/- 3 sigma.
You are at liberty to challenge the results produced in the datasheet but I would urge you to contact the manufacturer if you have an issue with the result or the test method used.
As an engineer that worked in Industrial automation industry utilizing inverters (VFD) in very hot environment like paper and steel mills I can assure you that electronic equipment is not happy being hot. I'll bet roof temperature in summer could easily get to 120 to 130 degrees. Personally I'll keep my extra cash in the bank and go with high quality string inverter.
Datasheets are the backbone of all electronic design and the key to maximising efficiency and safety. Without accurate data, it's all guesswork. So, the question you should be asking is
"Do I trust the company producing the datasheet?" a lot of cheap imported stuff makes outrageous & unrealistic performance claims, often promoting hazardous use. The secret is to avoid Amazon products with no vowels in the name and stick with brands you know and trust, even if the cost is higher. Burning down your house can be very expensive and losing your life.. well.. nuff said..
There isn’t any inherent problem with datasheets, and it’s easy to spot the rare situation where one is inaccurate or even fraudulent. What the tests in this kind of video are achieving is *system level* performance results based on factors that affect the whole system, especially when it’s only 1 panel amongst an array that is somehow compromised. It’s no fault of the datasheet that system-level performance isn’t reflected in them.
The huge advantage of optimisers is that the DC power that comes down from the roof can go straight to a DC coupled battery and charge it with no conversion losses. This power is additional to the 10 kW limit of the inverter and thereby allows more than 10kW of power to be used by the house if the panels can provide more than 10 kW. As home DC car chargers are introduced EVs will be able to be charged and avoid two current conversion losses.
Yes! If you have seen my other videos I personally prefer central/ hybrids over anything.
🙌🏼
Unfortunately it's also more dangerous to have all that DC coming straight off the roof.
DC has been coming off my roof for the last six years with no issues.
@@johnrogers1423 It's never an issue until it is.
@@Mavisto2"dangerous" is all about how one manages risk: Clipping, shutoffs, shunts, etc... Unprofessional (whether individual OR "certified" contractor) installation = "Dangerous". Asking EVERY question in depth, even when one thinks one has them all covered is how "Dangerous" is removed from the equation. This is not new tech and the field of managing DC is very mature. It's only when someone decide to be willfully ignorant (ie: lazy about asking) or cut corners on necessary costs that risk becomes high and dangerous becomes real.
A very interseting test was done in Europe over a period of 1 year comparing a string inverter with both optimisers and and microinverters featuring real world typical shading (not heavy shading). The result was that there was so little advantage to either optimisers or micro inverters (like 2 or 3%) that you were better off just making up the difference with an extra panel or 2 which was more cost effective. In a heavily shaded scenario there may be a place for these technologies, but once again, they're expensive. A couple of issues with micro inverters : you lose flexibility that you might have with a DC system. ie - you could directly charge a home battery with a DC -DC coverter rather than going DC - AC - DC and if one des fail in the middle of a panel group it involves getting a technician on the roof, lifting panels and replacing the unit.
Yes I have read about that test and you are very right, with no much shade, its best to just remove possible points of failure all together.
I also agree with lack of flexibility if using micros when it comes to future battery retrofit.
\Thanks for sharing your thoughts and experience on this.
no high DC or arc faults - future proof if panels need to be replaced and that voltage panel is not around and panel level monitoring as your warranty insurance with black start and 25 year warranty available - enphase for the win
I'm still learning but doesn't the micro inverter setup give redundancy whereas the string system basically the whole system or at least one whole section goes off line if there is a problem? That's the big thing people keep mentioning when I look for comparisons between Enphase and Solar Edge, that the SE system can see whole sections of panels go offline when there is a problem, whereas enphase just one panel or even just one part of a panel?
Totally agree, get the extra panels, the cost effective route.
Keep in mind that Enphase is also taking their AC reading AT THE SOLAR PANEL... whereas the Tigo / SMA reading for AC is at the SMA inverter, presumably a lot closer to the house utility panel... closer to the loads. Each leg of the Enphase is coming down at 120 volts vs 400+ volts DC for the Tigo/SMA system. So it's not inconsequential... could be another 4 or 5% less yield. Lastly, to get a real reading, you should be using a third party meter for both systems, at the point of connection to the loads. Maybe some CTs could do that.
Enphase is 240V not 120V.
The production CT’s on emphases is inside the combiner box.
@@slagmaker6780 each leg, so 120 times 2
Back in March 2020, I got 3 groups of 4 panels powered by APS microinveters with a small device that looks like a wifi router that reports the power output through wifi / internet. This small device didn’t cost USD 700, it was in the neighborhood of USD 150 if I recall correctly. It didn’t need a central unit, all microinverters were connected directly to my house’s power panel. Each microinverter takes care of 4 panels, so I bought 3, plus cables. I bought the whole system as a turnkey from a small firm led by a real electrical engineer. In comparison to a centralized system which he also quoted, without optimizer, there was a 20-25% difference. Based on the performance criteria, as it was an investment for 25 years, I went with the microinverters. I don’t know what the prices are at the moment (I’m not in US), but I guess adding an optimizer would decrease the difference, and still 2 issues to be addressed that you didn’t mention: electrical safety and future maintenance. Electrical safety: a centralized inverter with 12 panels in series would amount to 600V, before the AC output which is a hazard (in factories, 440V requires specialized technicians, individual protection equipment, etc), while the microinventers are dealing with 50V in parallel before the AC output, and the 3 inverters are independent from each other. Maintenance: although panels have 25 year warranty, the inventers probably have 5 years (perhaps 10 in some cases). If a centralized inverter goes down after the warranty ends, you have to pay 100% of the system price to replace it, and during that time you get 0% power from the solar panels. In comparison, with microinventers, if one goes down, in my case I will pay 33% to replace it, and still will have 66% of the power. Those are important aspects to consider. My system will have paid back itself sometime this year, I’m paying minimun consuption for my electricity provider, with still 2000 kwh in credit. Water heating included, I moved from gas to electrical. Last point, scalability: I added 4 more panels last year with same type of microinverter, no changes in installation besides adding the new group to the app control. I don’t know how it works to add panels with a centralized system. I did this because I got an EV as a company car, and now I save also on fuel. Best investment in my life, no taxes for the savings (I pay less tax now I my utilities are reduced), and continuous cash flow that will help a lot when I retire.
That’s a good point. I don’t know about every sting inverter, but the two that I have seen have multiple input strings where voltage isn’t allowed over 440V. On my own SolarEdge system, the optimizers (regardless of how many on a string) adjust so that operating voltage is 400V.
No battery backup?
@@imnguyen6658 battery system not affordable here. Perhaps in the future. It would cost multiple times what I paid for the system itself. No business case currently
Great video and terrific testing, your customers are very blessed to have an awesome business owner that actually has tested the systems and can recommend the best solution for their needs, keep up the great work you are doing
Thank you so much for saying that. I really really appreciate it. :)
You completely missed the fact the the warranty on the sunny boy SMA inverter is 10 years and will need to be replaced after about 10 years for additional cost. The warranty on the enphase inverters is 25 years and will last the life of the system without needing to be replaced. This would add an additional $5,000.00 (replacing the inverter twice) to the TIGO / SMA system over the solar panel warranty life of the system. I designed photovoltaic systems for 3 years for SolarWorld to include hundreds of residential and commercial systems from 3,500 W to a 1.5 megawatt system for an airport in the Dominican Republic.
May not be reliable info, but I was listening to a paid program by Solar someone. SMA was matching Enphase warranty. I think your comments are valid. 😅
My neighbour is at is 3th inventor in 16 years. The full production was off for one week x 3. If this happens with a micro , you will only loose one panel.
Another great video! It would be important to include a failure rate analysis of both products. This is a big factor for most installers. I worked for Fronius and now work as an Application Engineer for Enphase. At Fronius, we paired the inverter with a Tigo optimizer, and the feedback from installers said the failure rate was higher than other products they installed. Working at Enphase, I don't really hear about any major issues. Once in a blue moon, I do hear that a surge from the grid can cause the microinverters to fail. I would like to get your feedback. I love your videos, keep them coming.
Thank you for sharing! Yes I definitely want to do a video on failure points. It would be interesting to see, especially with Hoymiles making a big entrance.... :D I would go Enphase over any micro anyday, but personally I am more of a string inverter type a gal :D
Thank you for sharing your history in Solar
Would be interesting to see individual output of each one of them under cold and hot conditions.
Good idea! Need to test this winter a lot and then we can compare with summer 100+ temps!
Thanks for this highly informative and straight to the point video. Please keep them coming. Nice athletic moves too.
Thank you for watching and also leaving a comment. People don’t realize how helpful it is with the RUclips Gods 😂🤍
To me the value of Enphase isn’t a slightly better or worse production. It has to do with no single point of failure and proven reliability no other inverter option can touch. Great video!!!!
@@macmierzwa5361 the 5 year warranty is because of the envoy potentially having compatibility issues in the future and Enphase not wanting to be on the hook to create a whole new component to communicate with future wifi or cell signals we currently don’t use. The other aspect is simply the combiner box which you can use a generic sub panel instead if you’d like. When the was the last time a normal electrical panel failed on your watch? I’ve literally never seen an Enphase combiner fail in 7 years
As long as a micro-inverter in the centre of an array doesn't fail and you have to remove many panels to get to the dead inverter. It happened to our neighbour. Absolutely dead unlucky, but it goes to show that whatever can go wrong, will go wrong, with the most inconvenience possible...
Had Enphase inverters installed in 2014. Currently running with 5 dead inverters. Even though Enphase will warranty the inverters, the cost of removing my panel array to identify which ones have failed is simply not worth it. I had 3 systems installed at the same time, 28 panel systems, on 3 different houses. All 3 systems have experienced similar issues. I was gun-ho on Enphase in the beginning, not so much now.
@@meko1896removing the panel is like a 3 minute job for a contractor. They could be in n out within an hour and 5 new micros installed
@@meko1896hi, I’m not very experienced. Just wondering why you’re not able to identify the failed micro inverter in the monitoring app?
Thanks for all the effort you are putting into your videos to make it digestible. These tests could be boring but you make it very entertaining! Thanks again Martyna.
I am so happy you said that. Thank you so very much for the kind words. I was honestly worried they will be so boring. Next time maybe add a joke here or there or funny facts or sth. :)
Fantastic video. My system was installed in 2016. There was no such comparison video back in 2016 when I was choosing between Tigo and Enphase. I ended up choosing Tigo and, seeing the results of the video now, I think I made the right choice. I currently own stocks in both companies.
Thank you for sharing and yes I do too! :) Tough times in solar industry now but it will come back up!
The thing that strikes me as weird, is the changing relative outputs between the two test setups (considering only the unshaded panels). And the changing efficiency of the string inverter. At first I thought it might be temperature. That is, as the optimizers warm up they produce less, but later they were back to beating the microinverters. And at one point the string inverter was 95% efficient, and the very next test it dropped to 84%, but later bounced back to 93%.
I wondered what sort of load you used, and concluded the simplest and most accurate would be to simply dump all your power to the grid. It doesn't matter if you're dumping 1KW or 3KW (per test setup), the grid voltage should hardly change. So it really comes down to how much the inverter (micro or string) _wants_ to dump onto the grid. Which is a little like an MPPT circuit hunting for the optimal mix of voltage and current to maximize output power of the panel. In the inverter''s case, they might output 239 VAC, 240 VAC, or 241 VAC, and that 0.4% change in target voltage can make a much bigger difference in output current (maybe as much as 5%), which could totally account for the ping-pong performance difference between the two test setups.
So perhaps the overall power output difference (because it's so close) is irrelevant. The interesting result is the effect of shading panels on both systems, which also seems close enough to be largely irrelevant. The conclusion I come to is, buy which ever one you want. They're both good.
Hey Scotty, so true and I was also very suprised by the change in the DC to AC conversion. I so wish we could see the DC input of the microinverters, and compare to the AC output. Most major inverters whether string or micro, are similar in the efficiency so its very interesting to see those difference.
Just like you concluded, at the end of the day, the homeowner has to decide, since they are both very good! :) Thanks so much for leaving a comment!!! :)
In my case I simply paralleled the panels in the attic and ran heavy DC to a central inverter. Less trouble, works great.
Thank you for sharing and leaving a comment! :)
Thank you for sharing and leaving a comment! :)
It would be nice to also have seen a full day of non-shaded production. I get the feeling the micro inverter may have performed at least 10% better over the course of the entire day. But i think you are right in your summary in that it really depends on your situation and needs.
Finally, REAL shade testing! (Like from a nearby tree, chimney, or building, etc.) that STILL allows indirect sky light to reach the shaded cells. Guessing this is a first on all of youtube... Well done.\
Thank you so so much! 🙌🏼🙌🏼🙌🏼
EEVBlog got hammered by the coax cable from his roof antenna. in the afternoon sun.
@@robertsmith2956EEVblog’s shading issue was without optimizers. That’s exactly the problem optimizers try to solve - and judging by the results in this video, it seems to do it very well
This (and also your last video on shading tests) is just fantastic - thank you! 😃
Thank YOU Gary! Your RUclips is so inspiring as well! Thank you for all the work you do.
We have 48x400 W panels on our roof. Feeding into a Sol-Ark 15kW unit. We have not gone with any optimizers since the panels are mostly on the second story roof and unshaded by trees. That being said, one string of eight is often shaded by a chimney stack, blocking its production for much of the day. It may be better to move a portion of those panels to the adjacent rough surface to eliminate the chimney shading. That being said, we still produce over 15 KW when the sun is mostly overhead. Enough to meet our needs by far. I think one also has to look at the additional failure points by adding an optimizer to each panel. Pros and cons. Good video.
Hey! Thank you for sharing your system set up, and yeah you are very right, avoiding those extra points of failure is a good way to go. If you are happy with your system output, that's what matters. anyone can always say:" It COULD be better. BUT its great as is and you're happy with it. :)
I love Sol-Arks!
Been waiting for part 2 of your test. Thanks.
So glad! Thank you for leaving a comment 🙌🏼
Excellent comparison video. Easy enough to understand.
As an electrical engineer, I REALLY appreciate real world testing. This is first time I've seen any comparison video for solar panels. While I would have loved to see better numerical comparison when comparing AC to DC output for individual panels versus an entire set of panels, the point is not difficult to glean.
If you haven't already planned it, I'd love to see the same comparison for batteries; that would be awesome!
Check out neo Volta. I had the 24K installed and it runs my whole house except for the central AC which I keep on the grid because it sucks too much electricity anyway. But I installed 110 volt mini split if there ever was an outage on the grid.
Love your experiments and am looking forward to the other testing mentioned in your replies. I've DIY installed two 4.5k systems on my south facing roof with minor shading. One system is a SolarEdge 3800 and the other is Enphase IQ8m's. Surprised that the Solar Edge has consistently out performed Enphase day in and day out by a solid 5%. It will be interesting to see how your test goes.
Oh wow! Thank you so much for sharing!
This is very interesting! What type of panels did you use if you don’t mind me asking?
The great thing is that this truly depends on so many factors!
Thank you again for sharing!
The SolarEdge install has (14) Canadian Solar cs1k325's. It's almost 5 years old . The Enphase install uses (8) rec365aa's and (4) rec395aa's, it's not quite 2 years old. To tell you the truth, the reason I have this setup is that I was in the process of completely converting to Enphase, but with the performance issue with Enphase I've decided to go a different direction. I'll be adding whole house battery backup and V2H EV charging in the next year or so and right now I'm leaning towards a Sol-Ark 15 with their new optimizers - we'll see.@@solartimeusa
Really nice video, but you didn’t finish the cost vs net gain…if Enphase gives you 3% more - these “savings” offset the extra cost and your pay back time alters? Keep the trials going nice to see real world examples rather than the usual marketing blurb…..
Great to see side by side empirical data cutting through marketing hype. Well done.
Much appreciated! Thank you for the comment!
Power is not the only benefit from microinverters. Redundancy and expandability are other major, major, advantages of microinverters. Also, reparability, guarantee term, ease of troubleshooting are other things to consider. Microinverters are a solar game-changer.
If you have a minute check out my string versus micro from last year. I wonder if you would agree with some of the points you and I make.
Thank you for this brilliant experiment. I have Enphase and I’m happy with the microinverters, but the cost was more.
Would be great to see how the iq8+ compares to the iq8a on the 400w panels
Thats a future test for sure! Thank you so much for leaving a comment and hopefully you will stay for future videos/tests :)!!!
Happy producing!
@@solartimeusa This was 3 months ago and still no test between the iq8+ and iq8a. I don't know the difference but I think that the plus can be used with more powerful panels.
You might get 10/10 on it. One of the best video on entire RUclips ❤❤❤
Oh my gosh! THis comment made my whole day! Thank you so much!!!
@solartimeusa I'm doing research on Solar, and I found that you made one of the best videos on it. No one did this much deep analysis on RUclips. Please keep it continuous 💐
I think these tests, and analysis were excellent. thank you so much, I would give you all an A+
I so appreciate you leaving a comment! Thanks again!
I thought you did a wonderful job! I was also pleasantly surprised that you compared the cost of both systems in the end as well. It appears that the greater efficiency of EnPhase won't recoup the extra cost over the life of the system.
I was surprised the shading test are not comparable with cloud cover. It appears the Tigo system does better in low light. The cloud cover you mentioned was very small.
I would be interested in a test conducted across different cloud cover conditions. That will take time to collect for sunny -> heavy cloud cover.
I definitely want to get those tests done soon! Thank you for leaving the feedback!
Thank you for the testing. Most of my experience is with solar panels on conversion vans so relatively smaller systems. I didn't realize that optimizers could help so much with shading challenges
Thank you for leaving a comment, and sharing. :) Appreciate it so much!
Looks awesome to see testing videos like this. Thanks for making videos on solar.
Thank you so much for taking the time to leave a comment, it means so much to me! :)
Your test solidified my choice for SolarEdge Power Optimizers and the string inverter. The difference in cost compared to my neighbors who went with Enphase and micro-inverters is so drastically different I try not to tell them my actual cost....
One more aspect to discuss and possibly test is the power loss difference between DC and AC power running along possibly long wires, from one side of the roof to the (SMA or SolarEdge) String Inverter (for DC) or the IQ Combiner box (for AC).
Why understanding is that running DC power along 50-100 feet of wire might incur sugnificent power losses, which is not the case with AC power, which makes the conversion from DC to AC closer to the module a better choice.
What are your thoughts about that?
This field test didn't really test that, since all the wires are very short, which will not be the case in real-life applications, when the panels are spread along the roof area(s) running long wires from the Tigo (or SolarEdge) Power-Optimizers and Enphase Micro-Inverters.
Thank you Martyna for describing by conducting different tests and arriving at concrete results to decide which may work best in a given situation. I will watch this clip again and again and highly recommend to individual(s) who may have doubts in their heads on deciding which system to go for....By the way that athletic flip was hilarious.
Thank you so much for leaving a comment, I am so glad the test was helpful! :)
Great video and the testing was very intensive. I have the Solar Edge optimizers installed just a couple of days as I realised later but I think overall with a power production guarantee for 25 years from almost every solar company, it may not be a big difference.
I will be testing SolarEdge against Microinverters soon, but you are correct! The difference is so small, I really don't think you should regret anything, and especially if shading is not even an issue. You should feel good! I like customer service with SolarEdge, they make it really easy to replace faulty units, and are pretty quick about it too!
Maybe a bit different but would like to Tigo vs Victron energy MPPT controller video.
Hey Martyna, you're a natural in front of the camera, I really like these tests, and I don't think you can beat a basic string inverter without optimisers for simplicity, you may lose a tiny bit of production, but for me the less electronics up there the better. PS You can do cartwheels any time you like LOL !!!
Hey Andy, Thank you so much for leaving a comment, I really really appreciate any support! And I am 100% on the same page as you as far as the string inverter goes! :)
Good video! Test 11 is more relevant than the other tests which used leaves and cardboard. In real life, panels never see full shading that the cardboard presents, diffused shading from chimneys, vent pipes, trees, and structures is what we actually experience.
I was the first installer in Arizona to use SolarEdge. Split my 24 panel array of Trina 230's in half and put SolarEdge on one half and the old Zantrex string inverter on the other half. Virtually no shade. Guess what? Zantrex won by a smidge every day. Since then, half the SolarEdges I installed have failed.
Would you rather have an ultra reliable array running on a string inverter where you can't see the individual panel results, or would you rather have a much less reliable optimized array that you can easily see the failures?
I am solar permit designer in india and I appreciate your test it is eye Operner for me because I thought there are significant energy dropped in inverter system if there Shadow shade on pv system but there no much different. But in term of costing it is worth. And keep working and testing for ❤(inverter) of solar system. Thank you
Great experiments. Thanks! My understanding is Microinverters have a 25 year warrenty, and regular string inverters a 10 year warrenty. Figuring in the need to have to replace the string inverter at least once or twice over the 25 year warrenty on most solar panels (plus installation of it), and the roughly 3% more production of microinverters, the microinverters seem the most long term cost effective solution.
Thank You for All that you are doing for our Planet Earth.... Peace.. Shalom.. Salam.. Namaste 🙏🏻 😊 🌈 ✌ ☮ ❤
Oh what a change to see such a good, simple and well expressed trial. Thank you.
Thank you so much for being so kind and leaving a positive comment ! :) I so appreciate it!
As a avid tenter the most important is battery tech so or more videos you test between using different battery tech to see what is the best/and cheapest batteries to use in their systems!
It also depends on the quality and tech of the panel and the comparability of the brand inverter.
Some panels just go better with certain brand inverters and some clash.
As a generalisation premium panels with good micros will outperform a string inverter system with optimisers.
Lots of efforts to put together two solar inverter systems and carry on the experiments. Thank you for making this comparison video. Also conclusion is also very clear. If during a day shadows come and go on the solar panels, go with micro inverters. If there are no shadow issues, go with one central one inverter and save some money on the equipment. Also get more power in caparison, since no shadow issues.
Thank you so much for leaving the comment :) I so appreciate it!!!
A brilliant test and great, very clear video with clear easy to understand graphics, thank you!
I have an East/West roof and will fit panels in each direction but a sizeable chimney in the middle to one side (Victorian house) so will have varying amounts of shading over different panels throughout the day!
Very interesting!
I am so so glad!!! Thank you for leaving a comment!
Thanks, that was really useful. I wish to point out one small mistake in the costs ( @ 20:49), the IQ8A @$233 plus a Q cable @ $18 = $251, not the $241 which you have shown. Therefore the Enphase system is even more expensive by $250, but that is small compared to the total system cost which is $7008.
I'm so glad I'm not the first one to find the math error.
Great video. Would love to see the same test using SolarEdge. SolarEdge is what most EPCs are using along with Enphase. As well, it would be great to see the output by Enphase after conversion from the AC on the roof back to DC into a battery, and then AC into the house as mentioned in other comments.
great points and i have the solaredge inverter prepared to test it, just need to find time!!! :D I agree that would be great to see too. I mayb start asking those companies to send me their batteries to test, because its getting expensive haha!
A very interesting comparison, thank you.
It is worth noting that the Enphase system does not have a single point of failure. A dead Enphase inverter will stop production for one panel while a dead optimiser or central inverter will take down the whole system.
A comparison of cabling cost from the roof the central inverter/combiner box would be interesting. AC cabling is mass produced while high voltage DC cabling is more specialised.
It would be interesting to compare the AC power reported by the systems with a 3rd party meter.
Great video!
I had no idea about solar in 2015!
I got a system with
SMA Tripower AND TIGO Optimizers MM-2ES75 for ALL modules.
I am so happy since 2015 - NOR the SMA - NOR any Tigo had any fault till current time and contine to work geat!
Thank you so so much for sharing!!! I am so so happy you are happy!!
Hi, thank you for another great video. I like very much your approach and at min 19:49 you show that Enphase has produce 3 to 3.5% energy. What is also interesting to take into account is when you have battery storage. Enphase will have more current conversion than if you have a DC coupled with Tigo. At the end it would be interesting to see what you get out of your batteries.
That battery storage thinking peaks my interest and i would love to test it like that to see if the results would change!
@@solartimeusa looking forward to this video :) Keep up the good work
This is exactly what I am wondering. Especially for an off grid system that is mostly DC anyway, avoiding those conversion loss's is a big thing.
The one time I see the micro inverters as a plus is a grid tie system that does not have battery storage.
From all of the research I have done, any system with battery storage in it is better off with optimizers over micro inverters. DC-DC charging efficiency is almost always higher than AC-DC.
With solar getting more "common" I hope to see more DC appliance options. There are already DC refrigerators/freezers available, as well as ceiling fans.
POE systems are ripe for running off of a 48V solar battery system. That can currently cover lighting, some TV's, a lot of security systems, as well as ports for all sorts of usb devices.
Large loads are really the only problem area right now for taking a house completely DC.
I am also very interested in building sciences, and believe we have the technology, RIGHT NOW, to be fully capable of building houses that are self sufficient from an energy standpoint, at a reasonable cost compared to current minimum code compliant standards. The biggest problem is convincing people to NOT do the same old thing, but instead do it better.
having 10kw solar edge with optimiser , plus dc SolarEdge battery installed next week
To achieve this exact goal
Excellent video, very informative and real comparation side by side. I know you took the avg price based on manufacturer, but IQ8+ can be found for little less than $200 each, and sometimes $150 each which bring the whole system down to $4.5k
I still prefer Enphase, I did a 8 panel installation in South America (where my family lives) and is the best solution, because I can expand the system very easy, and if one microinverter fails, is easier (in my case) to replace it vs the string inverter, besides only one panel will go down instead of the whole system.
Another advantage is less cables and only 220~240v max, while with an string inverter, it require DC protections and higher voltage per drop, but the later is a better option if you need a battery backup system.
Great testing, it's likely the most truthfull in the industry keep up with the good work. I have a strong belief in no shading for a roof and a simple layout string inverter all the way. If the roof is chopped up or shaded micro is worth it, and we use AP systems. Finally if it is a ground mounted we only use bifacial panels with string inverters and no MLPE at all.
Hi Martyna, love your videos! Thank you so much for conducting such great real life & head to head experiments.
Two questions:
1) it seemed like you had pretty significant DC to AC conversion losses on the Tigo/SMA side (10%?). Is that typical or were your AC CT readings a little off?
2) Enphase used to have a lot of reliability issues (compared to Solar Edge for example). But then Solar Edge seemed to have A LOT of problems with their HD series inverters.
Comments/thoughts on equipment reliability (as an installer) in 2023?
Lots of innovation on the Enphase side. Of course it’s not cheap.
Thanks again!
Jonathan
12.2kW Panasonic / 11.2kW SolarEdge installed in 1997.
Hey!!!
Yes so next test will be Enphase Against SolarEdge.
I was personally a bit surprised too at the losses from the conversions. Too bad we can see the DC input on the micros, along with the AC output. That would be interesting to see considering most inverters vether string or micro have similar efficiency ratings.
As far as reliability with ENphase, I got burnt years ago, so I am not too trusting of any microinverter, but to be frank, I have not experience a whole lot of replacements in the past 2-3 years, so they must have improved something! :)
SolarEdge seems to have a bit more issues, but they ALWAYS replace faulty units and even provide labor reimbursement, which Enphase does not have. I have had a lot of homeowners who bought a home with a pre-existing system, that was SolarEdge, and with no problem they transferred the product ownership to the new homeowner, and all warranty replacements went pretty smooth. So there are pros and cons to both...:)
As far as my preference.... I have to be super honest here. String inverter any day.... :(
I am very trusting of SMA, even though they aren't as popular... they are made in Germany, and myself growing up in EU, I trust the quality of those products way more than anything made elsewhere. But that could be my Polish-ness talking.
Thanks again for sharing your thoughts here, I so appreciate it!
Martyna
@@solartimeusa This is a very time consuming test and thanks for doing all that. I was wondering if you can redo only a small subset of the test with Tigo + Fronius inverter, the reason I am asking is that their global maximum point tracking system algorithm is different and in some complicated shade scenarios might produce a different result. Would love to see this but I understand this takes a lot of time and energy to do so.
I have Tigo and SMA and I can confirm that depending on weather conditions you will have around a 5-10% loss in the conversion. You will have less loss on sunny days. For instance I had a day with 98 kwh produced DC and 94 kwh AC. On the cloudy day i had 7.4 kwh DC and 6.6 kwh AC. I don't think her test accounted for the AC losses on the Enphase system as her results were from the micro-inverters not any down line CT's like the optimizers.
Thanks for the informative video. My first thought was to say that a great deal of difference would be seen if you have to place your panel array further from your house. For the string system you would either have to run expensive wire to carry the DC to the house inverter or you would suffer loss. The Microinverters would be much less susceptible to loss since AC can travel further on thinner wire without as much loss (which is why our grid is AC). Your testing of both arrays being adjacent to your building eliminated this from the equation. In my case the array will be about 100 feet from the house.
Thx a lot for testing the architecture of the panels by shading them. As one can see the diodes are working as intended.
Simple question: what's going to fail most likely, the panel or the electronics?
Hence, simple rule, do not build an electronic box per panel on the roof!
EXACTLY! Thanks for that comment!
Great and methodical testing! It looks though that at 10 AM there was still a bit of shading from the building behind on the Enphase side.
A thorough, informative video, thank-you Martyna.. Reading about the effects of partially obscuring panels and the effect this has on the different inverter configurations is interesting, academically, but seeing it done helps cement the ideas at play. Plus, your cartwheel was an unexpected little treat.. Keep up the good work..
Thank you so much for leaving your thoughts and sharing. I am sure I could have done this test in different ways or speak about it differently but I hope its a step into the right direction for good product testing. :)
Thank you so much for leaving your thoughts and sharing. I am sure I could have done this test in different ways or speak about it differently but I hope its a step into the right direction for good product testing. :)
I would like so much to see such a test with different solar panels brands, like Sunpower performance.
I know!!! I need to get to work on that! I really hope to get it done in the next month or so.
Thanks Martyna - a great myth busting video. This is what we want rather than sales hype.
Thank you for the kind comment!
It looks like neither system is a clear winner nor loser. It depends how much shadow can fall on your panels. De difference in installation costs is huge. But if you live in a place with many clouds, trees, buildings etc, over time the cheaper optimizer system might be more expensive. But if you add one or two more panels, it wouldn't make such a difference in initial costs and they could catch up with current lost in shady times.
I'm still learning and try to understand, before i decide to start with a system. Thanks for this video, it helped a lot.
What I believe is the most convincing result that you have presented is the substantial cost difference between the two. The other factor to consider is reliability of the two systems. The Enphase unit is really an optimizer (to do maxim power point tracking (MPPT)) and the DC to AC inverter all in one package. Enphase has to put the inverter section up on the hot roof were as the string system the inverter is usually located in a cooler area. Temperature is very import factor when it comes to reliability and the life of components. One of the most temperature sensitive components in electronics are electrolytic capacitors. The inverter section needs electrolytic's to to do filtering of the DC since the AC power is changing from 0 power at the AC zero crossing going all the way up to approximately 1.4 times the power output when it is at the peak power output. This happens 120 times a second for 60 Hertz USA power and 100 times a second for 50 Hertz European power. I once opened up a failed string optimizer and found no electrolytic capacitors located in it. They are located in the inverter. I never open up an Enphase but I believe they have electrolytic's' for the DC filtering. Even so the higher roof temperature still would negatively affect the reliability and life span for all the components which includes for the Enphase the inverter section. Also in the Enphase system the inverter has to be duplicated for each panel this results in not only in a higher cost but due to the higher component count it will effect reliability as well. The string inverter would have approximately the same component count as just one of the Enphase inverter section. In the string inverter the components would only need be larger due to the higher power output requirement. Many installers like the Enphase because I was told in the beginning they offered the installers a generous warranty payment when a failure occurred. I don't know if this is still the case but they more than likely they now stick to what they know. By the way I thought the cart wheel was impressive. :-)
And adding a suggestion: you should test one shading condition at time.
The way you did you'll always have a dominant condition that will have the biggest impact.
As we cannot compare directly DC vs AC, it's hard to understand the final AC output result.
The biggest difference is a micro inverter system does not have a single point of failure, like a Solaredge optimizer system does that feeds into a single string inverter that can fail and shut down the whole system
Yet it does.... the combiner box can fail, can it not?
Not totally. It holds several breakers and any one can trip. But I haven’t seen many trip in my 14 years installing Enphase.
We have been replacing Solaredge inverters left and right every month. Screen or screenless edge systems.
Great video, fantastic comprehensive test. The fact, that covering 1/3 of a panel is as bad as covering half of the panel, comes from the construction of these - usually these are divided into two sections and such covering disables one of them completely.
What is more interesting - the power output from panels that are not shaded (let's say #2):
- 5:37 - microinverters 159W, string 186W
- 7:34 - microinverters 222W, string 244W
- 12:15 - microinverters 314W, string 302W
- 14:09 - microinverters 326W, string 332W
How can we explain this? Does increasing heat affect the optimizers more than microinverters?
Also, something very interesting happened at 16:07 - panel #3 without any shadow on microinverter gets 328W, while the one with optimizer only 240, identical to that one with "chimney". Why is that so, especially when at 17:20 it does not lose the power?
BTW, was the string inverter in optimal, chilled place?
Nevertheless, it is more important how this lasts throughout the years. Microinverters are exposed to extreme weather conditions (heat, cold, water) and this might shorten their lifespan. On the other hand, string inverter works with much higher voltage and wattage, which might also cause failures.
But summarizing - the actual differences were really small, and what is important - if you know precisely your lighting conditions, you may install optimizers only on selected panels, reducing your cost even more. However, having optimizers may help with identifying any problems with some panels - without them, you just don't know why your whole string performs worse than expected.
And still cost of microinverters is so high, that won't pay off ever. And installing PV is all about money, so... 😉
So to sum it all up: IT DEPENDS 🤣
When the panels were all clear and it was sunny did you see any clipping on the Enphase MIs?
Great question, and unfortunately I did not test the panels with no shade in the middle of the day, BUT that is a test I will be doing very soon.
@@solartimeusa sounds good. keep up the good work
One consideration for some may be that micro inverters are subject to EMP destruction (whether natural or anthropogenic) while the all DC PV PNL systems are robust with respect to EMP. Centralized AC inversion within the building structure may of course be remotely shielded.
The case for AC of course is made where long cable runs from the PV PNL’s are required where DC I squared R losses become significant. Philosophically I favor maximizing DC thru out the house both for DC reliability and electrical efficiency. This is why Auto, Marine, Aircraft, and electronics utilize predominantly DC. Where AC is required over distance and for AC appliances one must accept the inefficiency of conversion. With AC comes both efficiency losses of conversion and parasitic losses of maintaining inverters operating in standby w/o being loaded. These losses in turn must be alleviated with more PV PNL’s and larger batteries.
Martyna, Thanks for empirical testing instead of biased sales pitches. 👍t
Be sure to also consider access - micro inverters under every panel may be impossible to access to replace one when it fails in the center of the array without removing many other panels to get to the faulty one.
THANK YOU! Yes, very very important point to consider and i 100% agree.
Very interesting. I guess there is a crossover point where the Enphase may be cheaper, since you have a big central box in the string inverter case. I'm not a fan of optimizers because of the added complexity and cost, but microinverters add to the benefits of optimizers by removing the amount of hvdc cables routed around the house, and they have excellent warranty too.
Very nice Video!
When it comes to safety Micro-inverters may be better as the TIGO's always let the high DC Voltage thru.
There are however "Huawei" and "Solaredge" Optimizers that don't output Voltage unless the Inverter is active!
With the TIGO's I would only put them on the panels which are expected to be shaded.
(trees, chimneys and overhead power lines etc...)
Thank you for the video. It was very enlightening. On the sad note: this is such a bad morning / low light result for Enphase. I bet, Enphase on a cloudy or low light winter day will half your output. It needs more power to do a better conversion to AC, this is why early in the morning in your test, it was 40%-45% less then Tigo (raw power), but by noon they almost leveled off with no shading. In addition to this you will lose another 10%-15% again if you have a 48V battery backup system to charge with Enphase system.
Great, next test should be how both system perform for different orientation of the panels
That would be such a cool idea! Lots of people always wonder at what angle should they have their ground mount system at. Thank you for the idea! 💡
@@solartimeusa Yeah right? I was wondering if optimizers would perform ok with mixed roof orientations, or if it is better to go with microinverters all the way. 🤔
What do I think? I'm a Brit and your description of a "cloudy" sky is our version of a bright sunny summers day.😂 Secondly the amount of panels you guys can fit on your roofs is probably almost three times more than a lot of houses here.😂
Joking aside, thanks for a brilliant experiment it really helped explain the actual differences between micro-inverters and optimisers rather than the technical ones. After all what is most important to a home owner, how efficient it makes your panels or how they work and why they do what yhey do? Simply how efficient they make the panels in comparison to how much they cost is what we need to know.
Nice comparison, I live in Estonia and get completely different results and the Microinverters are working only from April to September.
You should repeat this test in Ohio in a winter month and you get complete different real life results
I definitely want to do repeat of this test and test other situations as well. Thank you for the ideas :)!!!
@@solartimeusa
I am waiting for it. Texas // Ohio
Have a nice day and happy continuing
Would be interesting to see a similar test performed using a different set of solar panels - panels that utilize a 'shingled' style interconnection of cells (effectively a series string of parallel-connectef cells). Would expect to see outputs in more direct proportion to the percentage of panel shaded.
Additionally, it would be more realistic, I think, to use a shadow generation technique that still allows indirect illumination of the shaded portion of the panel since that more closely mimics typical shading VS applying an opaque 'shade generating' shape directly to the panel surface.
Just a question at 9:21 Tigo was making 2095w DC and normally the conversion to AC was less than 100w however this time at 9:26 SMA shows 1765w why the major reduction from DC to AC? Again just a question why the conversation not remain within 100w from DC to AC? Is the unit getting hot or something?
Also at 20:43 the math seems wrong 233+18=251 not 241 so thats 6,275 .. also the price difference would be even grater if you used an EG4 6000XP inverter for $1.3k vs a Sunny Boy for $2.4k just saying, however i get the point.
Great video, with the outcome that the micro inverter technology is incrementally more efficient while solar energy is being generated.
What the efficiency variance between the technologies factoring in solar battery charging and pulling the power out for AC use when solar power is not being generated.
I have a lot of intermittent shade and multiple small roofs so determined I would be better off with microinverters. After two years, they have worked as expected and I have no regrets. Obviously if I add a battery I will need an AC coupled battery so the extra AC/DC conversion losses may be an issue. I did a TCO cost over 10 years and for a 10kW system the microinverters cost about 10% more overall, but on a cost/kwh of generation for me the microinverters were 20% cheaper than a multi string DC inverter setup. Also, reliability of the microinverters is anecdotally better than DC boosters. TBH, either system will pay for itself completely in under 6 years so ideciding which solar to get is less important than deciding to just get solar.
Bad math. Your calculations should be as follows:
233 + 18 = 251
251 * 25 = 6,275
+733
= $7,008 vs $4,116
What were the make & model of the solar panels that you used in your experiment? I'm curious to know how much actual wattage you monitored vs the STC wattage of the panels.
Well done video, by the way. That was a well thought out & well executed video! Ty!
HEy! We used REC 400 W ALpha Pure Panels ( premium)
Thank you for the corrections and leaving a comment! :)
HEy! We used REC 400 W ALpha Pure Panels ( premium)
Thank you for the corrections and leaving a comment! :)
@@solartimeusa Those are pretty high grade panels. I'm a bit surprised that you only got 328W max from a 400W panel under full sunlight conditions (yes I'm aware that you experienced partly cloudy conditions akso, but there were definitely fully sunny conditions too.)
328/400=82% of the STC. Even if the day was very hot, the % loss from high temps would likely be less than 3% of the STC rating.
If you measured a higher peak wattage than you showed in the vid, what was the max for those panels?
Just want to say THANK YOU for ALL THIS WORK , amazing testing.
THANK YOU for being so kind and leaving a comment!
Thanks for the video - great testing. I do have a couple comments, though. It looks like there may have been some shading that wasn't yours. In the morning the values on the unshaded panels tended to be higher on the Tigo side and in the afternoon they were higher on the enphase side. That seemed to impact your numbers. The panel next to the panel with the small chimney shadow was lower when you were testing, which you noted, but this indicated a shadow from another source (like a cloud), because in the next test, that same panel next to the small chimney shaded panel was back to the value for the unshaded panels. Obviously this is hard to control for, but it just means these tests are approximate at best. Again, though, I do think this is great info.
Your testing is easy to follow and understand. I would like to have seen a no shade at all daily total
Thank you so much! I will be doing lots more testing soon. :)
Hi... From Malaysia with love 😀 Thanks for the great effort.
Thank you too! :)!!!!!
Thank you for this. I'm debating between a Victron 1200-watt Inverter or microcontrollers. At the 1200-watt system size, the cost is exactly the same. I think I will go with the Victron only for a better-quality product even though it means running DC cables longer than if I ran microrcontrollers at each panel. Of course, it will also mean I won't have microcontrollers out in the sun/heat.
Great video. Would love to have a searchable title such as Tigo vs. Enphase, or something to make it easier to find based on your other video. Was looking for this for a long time.
Thank you so much for giving that idea, just updated it. Thank you again! :)
Seven words that make algorithms love You.
are....? :)
Great real world comparison test, would have been good to have compared against panels on a simple string inverter with no microinverters or optimizers.
More tests coming this summer :)!
thanks so much for confirming my hunch !!!! i've got a 70ft white pine shadow that transits my site
one extra problem you might wish to consider, is the failure of an inverter, on one Tigo/Sunny boy it knocks out the whole system (stops power generation until fixed and costs a lot to replace, on the enphase system. The loss of just one microinverter is only going to drop 4% on a 25-panel system and isn't hugely expensive to replace and it also does not knock power generation ..this makes the enphase systems huge amount more attractive cost-wise
Can you test SMA and Fronius string inverter on same panel set???? That would be cool test to show difference in shadowing controll in string and how MPPT controlls voltage and current!!
Nobody has done that!!
8 or 10 perc panels (410w), there is difference in line voltagecontroll in mppt. Depence who has make the string inverter
Another video full of hard data, very well done. The only point I would make is that the cardboard was 1/2 and 1/4, no where near 1/2 and 1/3. Doesn’t really matter as the testing was well done for both systems.
Yes it was! I realized that after we did voiceover, but left it to see if anyone would notice haha :) Thanks for leaving a comment.
Enphase is 8 MPPTs vs 1 MPPT string of the Tigo system. With extreme shading conditions Enphase has the output advantage due to multiple conversion points. They stay in upper 90% efficiency range. While the SMA inverter shows efficiency loss when not at peak output with a single MPPT string. Notice the SMA inverter out performing the Enphase when the solar input was higher in the morning tests. The only way to prove which is better is use an entire day production of kwh not just specific points of output. Run an 8-10 hour output test.
John
9.25 kwp with SMA SunnyBoy 7.7 DIY installed 2020 without optimizers
Hey! Yes, I do want to test more realistic conditions. Not applying direct shade but maybe place a "tree like" shadow on both arrays and let it run for multiple days, preferably one full clear sun sky, one with some clouds, and one rainy day.
Definitely want to do that to see how different the results would be.
Overall you are very right, rather than comparing individual outputs, looking at total production we get, would also make it easier for homeowners to understand.
The SMA / Tigo system is cheaper but they don’t offer 25 year warranty as Enphase. During that time you will have to replace the string inverter of SMA and maybe some optimizers and after that it becomes the more expensive system in addition to being more tedious. Also it will not produce electricity during replacement time. If one Enphase micro brakes down the system will continue to produce electricity.
Tigo has a 25 year Optimizer warranty. SMA 5-10-20 year warranty on inverters.
@@macmierzwa5361 for what it’s worth, my local library has 2 “Sunpower” string inverters, made by SMA I think, still working fine since 2008.
@@macmierzwa5361 It’s the string inverter that will fail long before 20 years whether it’s an SMA, Solaredge, Fronius etc. In real life however, it has most likely had to be changed for a bigger string inverter after 10 years when adding some more panels. Something, which is not required with microinverters.
I'm not 100% sure but it's most likely that the optimizer modules have built-in bypass diodes. If the main circuitry fails the rest of the string will still function.
@@eDoc2020 I think you are right. If one optimizer fails you will be fine (whole system is not down). It’s the string inverter that is the bottle neck / risk point.
With a minor additional panel cost, I'd opt to clip all day every day (if clipping is what I think it is).
In both cases the power reported is from the manufacturer's systems. I wonder whether that would match up with measurements taken by CT clamps near the consumer unit. They both have a vested interest in reporting a bigger number.
My biggest worry is reliability. My roof is very hard to access, needs scaffolding etc (not just a scaffold tower). So a single failure might cost $$$ to resolve, simply due to having to access the device.
I find the pinging (sound) annoying.
A different sound would probably solve that weird ping 😅
I didn’t even notice any pinging sound
The one variable that I believe you should have included in your test is the inverter efficiency
This has a profound impact in the total wattage produced especially for people that install battery storage on their systems bc with micro inverters, you lose more power as the power is converted from dc to ac (loses), then it’s converted back to dc at the storage point (loses), then at conversion back to ac (more loses) whereas with optimizers, the lose is only at conversion from dc to ac for usage
So I believe at the end, optimizers will carry the day