I have just switched to octopus go, I found your video very helpful in understanding all the tariffs, I can't get intelligent go for the same reasons. I have recently increased my battery from 7kwh to 12kwh and I am thinking of adding another 4.8kwh.
That's great, I'm glad I could help. I'd love just a little bit more battery capacity, maybe another 5kWh or so. We'd definitely be able to cover almost all of our Winter usage at off-peak rates then. If battery prices come down a bit more it'll become worthwhile, so maybe in the next year or two.
Got my EV a few weeks ago, charger installed yesterday and already on Intelligent. We've got 8.9KWp solar and 10 KWh battery but we also use a lot (average 17 KWh per day) of normal usage electricity (i.e. not the car or any heating). On most days our battery should last until 23:30 so I aim to get 95%+ of our consumption on the night rate so the calculation is obvious - which one has the best night rate? So I was delighted to get onto Intelligent. The only situation where I'd likely change this is if energy prices shoot up again and it's worth going back to Flux because we export an awful lot. Across 2023 we averaged better than 20p per unit for export and made a fortune. But while Flux export rates aren't much better than the Outgoing 15p there's no point. I've just looked at Cosy and it's interesting to look ahead for if we do get a heat pump. It'd probably require a fair amount of maths and analysis! I'd have to look at how much was being used and balance that against getting another 5 KWh battery because that would save a lot as well.
Yes, indeed, as soon as you're unable to cover a good chunk of your usage with off-peak power the calculation gets a lot more complicated. I'm having a think about how I could incorporate that into a future version of the rule of thumb calculation but I think it will inevitably be more complicated as it'd involve entering your battery capacity and a few other things, but maybe that's not so bad.
@@TimAndKatsGreenWalk There's so many variables I don't envy you trying to boil it down into a relatively basic way of comparing them! My situation changes hugely as soon as the schools break up. It's half-term right now, by 7am the kids are usually up and have my projector and amplifier on to play Minecraft or Lego Avengers for about 4 hours which doubles our usage and on grey days there's little chance of solar covering it. I could ban them from my man cave but then they'd be grumpy kids. And grumpy kids makes for grumpy wife. And nobody wants that.
I know, what timing! I put a community post out about that earlier today. I've already updated the values in the spreadsheet but I'll do a quick update video soon too.
@@TimAndKatsGreenWalkyes Go just got significantly better. Im on IGo but it can be a faff and its good to know that if i get fed up with it i can move to Go with little diminution, roughly £100/yr for me. (Essentially the difference between the off peak rate times however many kWh you use in a year)
Interesting Tim. This confirms my choice to stick with Octopus Intelligent Go for now. This will be my 1st winter on OIG so it will be interesting to see how we perform with 19kWh of batteries this year vs 9.5kWh last year when we were on a standard Octopus rate. That said I still have a conflict between my batteries & export when our car is plugged in & Octopus do a Smart charge session outside of the normal 11.30pm-5.30am IOG cheap rate period (when I pause my battery discharge to allow the car to charge). Basically when Octopus send the signal the car is forced to charge, the inverter see's this as a load & supports the 7.5kW charger (Zappi) with 3.5kW of battery power. Essentially this drains the batteries to the car instead of exporting to the grid. The only solution that I can see is to have my system rewired to feed the car charger separately from the main consumer unit so the inverter cannot see the car charger as a house load. Too expensive to do so I'll just have to live with what I have for the time being. This may be a point to bare in mind if Octopus finally approve your GE charger & car combo & you switch over to IOG in the future. That said with an all GE (inverter & Charger) system you may not have this issue as the inverter & charger should communicate with each other to prevent this issue.
Yes, I can see that would be annoying. As you say, we went for the GE EV charger on the assumption that we'd be able to charge the EV without discharging the home battery and that is indeed an option in the settings, so that was great. I just hope Octopus can get it integrated into IOG soon!
I went with direct car charging, just needed an additional Henley block, CT and consumer unit and cable. Definitely worth the small outlay to save the house batteries.
@@tebbo8324 👍 Humm. I have a spare CT & my consumer unit was replaced when I had the charger & solar installed. I also have a separate mini consumer unit installed that serves the PV system, Charger which has an integral meter. So, perhaps adding a Henley block & a bit of a re-wire is feasible without too much upheaval or cost. Add to the project list of "to do" & investigate list.
I've got the car scheduled hours the same as the charger scheduled hours. If Octopus tries to charge it outside of the offpeak time then the car will block it. It's a shame because I'd like to have that option available especially as we want to use green energy when it's being generated. But draining my battery so it's empty for the evening doesn't work. Interestingly (might be playing fast and loose with the word....) I asked a friend what happened to him in this situation and he doesn't have that problem. I'm friends with the guy who installed both our solar systems so I asked him and his install is different to mine. When his mains cable enters the house it hits his meter but then is split with one feed going to his main Fuse Board and onto the Solar Board, and the other side going to a Henley Board which connects to his Ohme charger. So the charger can only be supplied directly from the mains, it doesn't even know about the solar and battery. And vice versa, his solar app figures are completely oblivious to car charging. Whereas my charger is connected to my Solar Board so will make the usual priority choice of solar generation -> battery -> mains. I did wonder about having a Henley Board installed but it seemed like a lot of hassle to just be able to smart charge on the odd occasion Octopus make it available. We don't do huge miles in the EV anyway.
This was a helpful video, thanks. We have a similar set up; PV, battery, EV & Air to Air heating but cannot take advantage of Intelligent Go as we don't meet the compatibility criteria. We've been on the Agile tariff over the summer and into Autumn but definitely feel the rates are no longer proving beneficial, particularly where we would need to re-charge the battery around midday, prior to the peak period. We are therefore considering moving to either the Go or Cosy tariffs for the winter. I like the idea of heating the house during the night but it's not advisable to keep turning heat pump compressors on and off, as it reduces their lifespan. They can end up consuming more power this way too, as they work harder to regulate from a 'cold start' as opposed to leaving them on to maintain a consistent ambient temperature. It may be better to programme the consoles to reduce the temperature of your house during the day, as opposed to switching them off entirely.
Yes, what I mean by heating the house overnight is boosting the heat pump so that it does more heating during the off-peak period, so that has to work less hard during the day. I don't mean turn the heat pump off entirely during the day. Usually the setback temperature is reduced overnight but what I'm suggesting is actually increasing it when the tariff rate is low, then using your usual setpoint temperature during the day. If you can exclude your bedroom from that then so much the better since you probably don't want to overheat your bedroom overnight.
@@TimAndKatsGreenWalk Nice one. We're managing not to have the bedroom consoles on at all at the moment, as it's still relatively mild. The downstairs consoles are maintaining the setpoint temp for the entire house but as the temperatures drop, I think we'll adopt this approach. Thanks.
Only have solar and 16kw battery so sticking with Octopus Flux. Still charging and discharging at low and peak times. Will be interested to see how it looks at end of the winter period. So far even with low solar generation my stored overnight battery export seems to be cancelling out my overnight import costs.
I do need to implement a different "optimum" strategy for Flux and IOF, as I don't think they're quite right for either of the existing strategies in my rule of thumb for the Winter.
Spoke to Octopus and Givenergy people at Everything Electric Farnborough. Both blamed each other for the lack of progress with integration of the EVSE. Not very promising unfortunately, but hopefully once they work it out it will all happen quickly.
Next Drive v4, charge batteries and run heatpump from midnight to 7am, thats 7 hours at 6.7p, use the full batteries durring the day, if its a sunny day then export at 16.5p. At the end of the day then dump the entire battery at 16.5p. Approx profit is about £100 a month during winter depending on he size of the battery. EV is not required if you have solar and batteries
Interesting video thank you. I am on a FIT agreement getting an index linked payment of about 25p production plus 7p on assumed 50%export although because of a 9.6 Kwh battery export is actually nearer 15%. This will continue for another 8 years. I am on Octopus Go with a production of about 3400 Kwh and usage of about 3200 KWh per annum. This type of scenario is seldom covered in videos but I think I am on the best tarrif and would not benefit from switching to another export system. Basically my electricity is self funded now because of previous investment but when I change to an ASHP from oil and go down the hybrid diesel car route a rethink may be needed!
Interestingly the export rate for Go has recently been increased to 15p/kWh up from 8. I don't know if that would change your decision but it could make a difference to you in the Summer when you'd likely export a good chunk of your generation. Apparently it's possible to give up the deemed export portion of your FIT while keeping the generation part, which is handy.
My ratio for the last 12 months on IOF is 1.4. No EV + gas heating. Trying agile for the winter, will be interesting to see how it compares to last year, average unit rate etc.
Really helpful video thanks! You must face a big trade off with these videos between simplicity and covering as many potential scenarios as possible. I have a small battery and no EV. Am currently on agile but this made me think the cosy tariff is worth considering. As i see it the downsides are (a) lots of battery cycles will inevitably knacker the battery faster. Atm i do 1 cycle a day so increasing to 3 would be a big shift, (b) heat pump efficiency will take a bit of a hit if running the heat pump for fewer hours but 'hotter' to overheat the house during cheap periods. This strategy probably gets worse when its very cold and heat loss is higher. So it's not necessarily a no brainer. Agile has been a bit rubbish recently with lots of still, cloudy days but I'll give it a few more months and see what the rate averages out at. A slightly worse average rate than cosy might be outweighed by round trip losses from constantly charging and discharging the battery with cosy
Yes, it does get complicated very fast, it's a bit of a nightmare! The one thing I forgot to mention regarding Cosy is that not all battery systems allow you to set up multiple scheduled charge slots, which would make it annoying to manage. But if you can it's a viable option. I wouldn't worry too much about battery lifetime though; by the time the battery has reached the end of its useful life replacements will be cheaper and better, even if you reach that end of life sooner than you would by cycling more often.
We used Cosy from mid-Nov to mid-Feb last winter. Our GivEnergy grid-tied inverter only allows one programmed charging period, so I just reprogrammed it twice a day. It would have to be 3x /day now though, which is more of a pain. But the prices probably make it worthwhile financially. I reckon we would be paying on average 12.5p/kWh on Cosy, and we're averaging 11.9p/kWh on Go at the moment, so not yet worth it for us, but close. One thing that makes the picture muddier is if you are signed up for Octopus Saving Sessions, where they pay you for every kWh of electricity you cut from your typical use for an hour or so (usually somewhere around 5-7pm), on a day where there's high demand and low renewable supply. The winter before last, we were on Go, and got paid £75 over the course of the winter for joining them. Last winter, we went for a scheme from GivEnergy, where at the same times, they draw energy out of your battery and pay you more for it, having automatically topped it up just before. It's less hassle, but it didn't work well with Cosy because it stopped us charging during the afternoon cheap rate, then forced a charge at peak rate. We still made a profit out of each session, but our total for the winter was only £16.20. So I now need to work out whether Cosy will save us more than £60 over 2 months, or we might be better off with Go and Saving Sessions
One thing to bear in mind is that a 'charging cycle refers to a complete charge from empty to full, so if you charge from 40% to 60% five times, that's one cycle. For us, on Cosy, we could charge our battery by 75% in the 3 hour periods and 50% in the 2 hour period, so if we use it all, then over the three charging periods, we are doing 2 cycles. I would expect the battery retain reasonable capacity for a good 15 years at that rate (and of course, it only cycles that much in winter), but it will have paid for itself within 8 years. And it won't be defunct after 15 years, it'll just have a reduced capacity.
at about 5:15 you say GivEnergy EV charger is not compatible with IOG but I just ran my very similar system including that same charger through Octopus's compatibility page and it says it should work.
Thanks for the helpful video although my generation/consumption ratios range from around 0.5 in December to about 4 in June. However many of these Octopus smart tariffs are not available to those of us who just have solar and batteries, or an incompatible inverter. Also, how does Octopus Agile or Octopus Tracker compare with your favourite tariff(s)?
By all means grab a copy of the spreadsheet and add in whatever tariff you choose. Agile is tricky though because it varies so much, so you'd have to make some assumptions as to the average "off-peak" rate and whether that's likely to continue into the future or not.
I dont have an EV so im on Cosy Import and Fixed export, I also use Predbat which predicts my usage and manages my charge/discharge/import/export. I'll probably move to Agile again at some point over the winter when the average import price dips below Cosy's, that's when Predbat really comes into its own.
Very nice. Home automation isn't something I'm keen to get involved with but I can see how useful it is for this sort of thing, especially once you introduce Agile into the mix.
@@TimAndKatsGreenWalk Predbat is interesting, it knows when the cheap periods are (even the Intelligent Go ones that change) which is clever. I run Home Assistant too, I haven't really automated anything but I do find controlling the AC units easier with HA than the Toshiba app, and scheduling is much better.
As I can't get IOG, sticking with Agile - no doubt it'll be higher some days, and cheaper on others - but it's variability makes modelling harder unless basing on historic data.
@@TimAndKatsGreenWalk I added Agile to your sheet just by taking the average import price, basic I know but it gives me an idea on when to move to/from Agile
@@symonchester yup, that's how I would have done it, probably. It's very difficult to tell if it'll continue with those averages into the future though, which is why I was reluctant to include it.
Hi, great video and much appreciated. Im about to have my first system installed in two weeks, its all Givenergy with 7.2kw system 9.6 battery and a car charger. Would the Go or intelligent Go still hold true if you factor in charging the car through the night? I assume it would, but being a newbie i thought id check. Many thanks
Yes, in fact this assumes all your EV charging is done at the off-peak rate, so setting up to charge overnight is the right thing to do (just include that in your total consumption values). Good luck with your install, I hope it all goes smoothly!
@@gregcarnall9097 absolutely - but if GivEnergy is smart enough to charge the battery when the car is charging… then you can really benefit from extra half hours
I will add my view, indeed IOG is a great tariff, but atvthe end of October my 15kwh battery had depleted at about 9pm. So roll on cosy and my new ability to schedule 3 charge sessions. As you are good at speead sheets and a great understanding of energy tariff i think there is a very useful tool tobbe made. Breakdown 4 levels of heat loss. 3 , 5 8 and 12 . Then have four battery sizes 5, 10, 15 and 20. Peope could then select house size or in this case heat loss and then battery size. I think like in my case when youbhave a heat loss of nearly 8kw and a fairly large 15kw battery it can only be cosy that works. You also have the advantage of during yhe day when the battery is full the excess goes tobthe grid for my 15p export. Not a massive difference to my 12 import but no risk, ifbits sunny i get a discount if not its 12p then.
Indeed, I made the point in the video that if you're unable to cover a good fraction of your Winter usage with your battery using Go/IOG then Cosy would be a good option. The tool you're talking about is something I'm actively considering how best to tackle, but these things take time to do right so I can't promise anything. Keep an eye on the channel and you never know 😉
@@TimAndKatsGreenWalk cost cheap rate is ~10p, but you can still get 15p export. So it could end up being a good deal, though that could also end up being a lot of charge cycles!
@@JohnR31415 this is true but this is what the battery is for. I buy at 11.6p on cosy and sell at 15p. The differences is only small so I don't mind and gamble on full charge my battery and sell the small amount I don't use. Time can model the scenario using his data and add a simple multipliers to the heat load to simulate high heat loss. Air to air and water systems offer similar scop,s
I'm also waiting for the Intelligent Octopus Flux, as I have a Tesla Battery, so I can only get Flux. The Integration for that also has been set-up yet, but I've heard that Tesla and Octopus are working together. I'm still not sure if that will be better for me than Flux I'm on at the moment. Also with the Saving Sessions I'm again hoping this will help this winter, as I've gone for a 2nd Tesla Battery. Maybe I should have gone for a Heat Pump instead?
Well, if you look at the rule of thumb chart for the export strategy you'll see that Intelligent Flux is only better than Flux if you have a generation / consumption ratio higher than about 1.25 (that's the whole point of this chart!). If you know your typical generation and consumption values you'll be able to work out which is better for you for any given month. I'd certainly consider switching to Go/IOG over the Winter instead though, if you can. Especially with such a large amount of battery storage available to you.
Cosy seems a no brainer for anyone with batteries.. do you need to prove you have a heat pump? (currently on agile 16kw battery but use around 30 -40kw in a day only have granny charger for car)
It depends on the size of your batteries relative to your usage, as I mentioned in the video. If your battery is significantly smaller than your daily usage then Cosy can be a good option, yes. But for us we only use more than our battery can supply for a few weeks a year, so the lower off-peak rate on IOG is likely to win out over Cosy when taking a full Winter into account. Watch my battery sizing video to show how I was able to reduce our peak demand to almost zero once I adopted the heating overnight strategy: ruclips.net/video/_qysulne5g0/видео.html As for proving you have a heat pump, Octopus may ask for the MCS certificate but might not: octopus.energy/smart/cosy-octopus/
@@TimAndKatsGreenWalk yes.. looks like they actively check for installs (hmm could I ninja up and go and grab the serial number from a random unit down the street...) . grr That would be ideal for us. Pretty much guarantee a 99 quid a month electric bill over winter till the sun shines again. Where as we are around 150 on agile.
My understanding there was a legislative change allowing the entry of households to buy and sell their power on the spot energy markets. I’ve not seen any commercial offerings allowing this access yet, has anyone else please?
That's effectively what Octopus Agile is (although not quite how you describe, it's just done via the tariff itself). I suspect you're thinking of the Settlement Reform proposal, but that's aiming to make it easier for energy suppliers to offer tariffs, such as Agile, that follow the spot market, rather than actually allowing domestic customers to buy and sell power direct to the spot market themselves. I doubt that'll ever be a thing individual households could do. www.ofgem.gov.uk/energy-policy-and-regulation/policy-and-regulatory-programmes/electricity-settlement-reform
I have solar and a heat pump. I've switched to Octopus Cosy. I notice that right now -in the peak period- the house is using electricity from the battery and from the grid. Is there anyway to set a preference for the battery to be used during the peak period, so that it can then charge during the cheap dips?
That entirely depends on your battery system. You'd have to look into your specific settings. For our system we can set a timed charge period, in which case the battery will charge during that time and everything else will use the grid while the battery is charging. Then at all other times the battery is used to support the house (it's called Eco mode in my settings). I think I can only set up one scheduled charge period, however, so for the other two periods I'd need to do that manually (by setting an alarm on my phone and then manually setting the battery to charge, for example).
@@TimAndKatsGreenWalk Thanks Tim. I've found on the GivEnergy web remote control (go to My Inverter and look in the top right hand corner) the option to set up to 10 charge/discharge times. I've set three times to charge. I've yet to set discharge times - I presume I should set one between 16:00 and 19:00?
@@NigelPJ generally a battery in the appropriate mode should do that - if your using more power than the inverter can handle then you have to import to make up the difference.
Opted for cosy - first winter on ASHP, no EV. Running a Tesla 13.5kwh battery and 5kwh solar. At the moment the highest use per day is 22kwh running the heat pump off the outside temperature which seems to be the most efficient way of running it? Solar is still running the system on sunny days at the end of October which was a surprise. Just feel that with the ability to charge the battery 3 times and also running the house during the 8 hours of off peak (12p/kwh) this must be the cheapest way of doing things? Love drilling down into the geekery of the system so will try to work out other tariffs over winter ready for next winter.
Take a copy of the spreadsheet and add in the tariff rates for whatever tariff you like, then you can see how it compares to the others. But looking at the off-peak rates for Eco 7 it looks slightly better than Flux (except I don't think you can get as good an export rate - in fact it's not clear if you can get anything other than the SEG with the Eco 7 import tariff), but worse than all the others, so Go, IOG, and Cosy are all better in the Winter, and Flux is better in the Summer due to the better export rates.
I went live with an 8.4kwhp solar and 5.2kwh GivEnergy battery system on the 10th October and I’m on IOF as I don’t have an EV yet. For the 21.5 days of October my ratio is 1.42, if I look at the whole time I’ve been live my ratio 1.22. I’m on IOF but you said to ignore it as a tariff for the Winter/Self consumption chart. Given my potential ratio and no EV isn’t IOF my best tariff option?
Well, regular Flux would be better than IOF for the Winter as it has an off-peak period that you can use to charge your battery cheaper than on IOF. Use the chart and find the lowest line for a particular month, don't use your overall ratio as that will change dramatically over the year, getting much lower over the Winter. The reason I said ignore IOF on the self consumption chart is that you can't operate your system using the self consumption strategy when Octopus are controlling your battery for you. They will deliberately force export your battery in the evening, which is not what you'd do with self consumption. Use the export chart instead. IOF might well be better for you in the Summer but it's not a great tariff for the Winter.
I'm on octopus go. I would like to be on octopus intelligent go but it does not support my current setup. I had three phase installed. I then built a three-phase off-grid grid tide system with 82 KW of battery. My battery pack cost £12600 Each victron inverter was about 3000 (3x) I had to upgrade to three-phase power which cost me £2,000. I pull from the grid at 12:30 at night at about 45 kW. I'm normally fully charged within about 2 hours. I have a high base load of 1.2 kilowatts. I'm only using between 20% and 80% battery which is up to 90% in winter. I charge the battery up and then disconnect from the grid automatically. I only have 6 KW of solar. Which produces around 5 megawatts a year. I have a plan for another 20 kW of solar. For rule of thumb on one phase you can 10 kW of solar. I've been thinking about going down the water to air heat pump. But the costs were over £25,000 including the subsidy of 7000. I'm thinking of going down the air conditioning route. I think on average about £3,000 per unit worst case. I may look at adding more battery the goal of 120 kWh
I use Octopus Cozy in winter, since i'm using lots of electricity and I can charge up cheaply (12.5p/kwh inc vat, 11.88p/kwh exc vat) 3 times a day. Solar generation in Bristol is nonexistent at the minute with so much cloud everywhere, especially where I live. I have 10.5KWp of solar and generated 1KWh today, 1.9KWh yesterday and so on - hardly enough to make a free brew...and things will only get worse up until Christmas
@TimAndKatsGreenWalk It's been more than a few days for me...more like a month or more with the exception of a few freak days...when the sun does eventually make an appearance neighbours will think it's a sign of the 2nd coming or something...- we sure won't recognise it....
No indeed. By all means add it to your own copy of the spreadsheet in whatever way you believe is appropriate. It's too variable and unpredictable to include, in my opinion, as it's unlikely to remain consistent over any length of time. But don't let me stop you if you want to add it yourself.
I have 2.6kwh of solar, 14.4kw batteries, ASHP, and EV. I have an ohme charger which is compatible with Intelligent Go, but being on that tariff would cause my battery to deplete when charging the EV outside of off-peak times, which I absolutely don't want! So I am sadly still on basic Octopus Go.
Yes, that's annoying. There are ways to prevent your battery discharging into your EV but it requires some rewiring of various things, which might be too much of a pain. Our EV charger prevents our battery discharging into the car as both are GivEnergy, but sadly that also prevents us from getting IOG, so we're also stuck with regular Go!
I have 13.35kWp of solar, 13.5kWh of battery, Air-Air heatpumps (18kW between the two multisplits). Both EV chargers are Zappis and we're on IOG. The battery is a Tesla. I use home assistant to control if the battery charges from grid or discharges, based on the current electricity price. When IOG triggers a smart charge, it drops the whole house rate to 7p/kWh, and I immediately start importing everything I can - the battery charges, the 2nd zappi starts charging, the ASHP comes on and heats the house to a comfortable temperature (at 5.1COP!! so like 1.4p/kWh of heat!!). I never charge the cars from the battery. In fact I gain significantly due to the "extra" offpeak hours. Then when HASS detects the rate has gone back up, it stops importing and goes back to normal behaviour.
I've had 3.5kw of solar for 13 years, so I have done well with FIT payments. I'm buying extra solar and 27kw Powewall. I have ASHP and getting air to air as well. No EV, so I am thinking about Cosy with Agile export. I could fully charge the battery at 12.65p kw and then export most of this between 4pm and 7pm. It looks like I may get 20p+ for this. I will have along payback time so it will all help. Does this strategy make sense?
That could certainly work, as long as you're able to charge your batteries during the multiple off-peak periods. Not many systems allow multiple scheduled charges per day, so that's worth checking.
Just looked at a video on the Powerwall app and you can set multiple time periods for each tarrif rate. You don't specifically tell the battery to charge but apparently the app should work it out, as it knows to charge at the cheapest rate.
The rules for (Intelligent) Go is that you need to have an EV. Similarly for Cosy you need a Heat Pump. Do you have advice for those of us with just PV and battery? Currently on Agile, managed by Predbat btw
Yup, if you ignore the lines on the chart for tariffs you can't get then the next best one is regular Flux for the Winter. It's not an ideal solution but it's better than the standard Flexible tariff, for sure.
@@JohnR31415 Yes if I know I don't need the car until say 11 or even midday, I set the app to those times and quite often I get off-peak slots between 0530 and 1100 - which is great (my 7 billion cups of tea of a morning haha)
It doesn't appear that I can, no, sorry about that. That's not an option in the chart settings available to me in gsheets, so far as I can see (the font size is adjustable but not the size of the coloured bars, annoyingly). If you grab a copy of the spreadsheet you can change the colours to whatever you prefer, however, which might help.
On the chart editor under the Customize tab there is a Legend option. Legend Font size is in there (and defaults to Auto). In each series you can also specify a colour - just need to find a colourblind friendly set for the count of lines you’re using.
Can I ask a question that I should have asked before the summer. I just presumed, I’m sure somebody will know the answer. I have two separate installs. The first 3.5Kw of solar was installed under FIT. The second 4Kw with battery (8Kw Give Energy) car charger and diverter (myenergi). I claim the FIT. Can I also claim for export (I’m on intelligent Go), I presumed I couldn’t because I’m claiming FIT
The best thing to do would be to give up the "deemed export" part of your FIT and then get a proper export tariff for your full export. The deemed export is a relatively small part of the FIT and you'd almost certainly do better with a proper export tariff especially given you've extended your system. Call your FIT provider to confirm but I believe you will still be able to claim your generation FIT payments (which is the really good bit) even if you give up your deemed export.
@@TimAndKatsGreenWalk Glad I reread the comments before posing a similar question. I enquired about this when we had our battery and second solar array install, and was told we would lose the FiT if we did this. Perhaps I was misinformed, I hope so. If you can give up the deemed export and get a proper export tariff without losing the FiT generation payments, that would change everything for us. Tim, do you have a source that suggested to you this was possible?
@@TimAndKatsGreenWalk Good to know. I'll try asking Octopus about this. Perhaps the stumbling block is that l get my FiT payments from a different supplier.
@@markdearden1697 I'm sure they should be able to handle that one way or another. Yeah, definitely worth speaking to Octopus about it. I seem to remember there being something about FIT payments in their Flux FAQs, I'll see if I can find it.
Hello old friend. I'm on Cosy having done some pretty crude calculations to compare tariffs. Your comments have made me think that there is potentially a ration of battery size to consumption that would produce a rule of thumb of when Cosy - or other tariffs are better. Cosy is great because you get to charge your battery at the cheap rate 3 times: 2x3 hours and 1x2 hours. We could probably make some crude assumption about being able to perfectly charge and perfectly discharge your battery: so for most tariffs you get to charge once only, if your consumption matches your battery size you get all your power at the lowest rate. As your consumption goes above your battery rate, we assume you use at the day (not peak) rate. Cosy has a massive advantage, because you get to charge 3 times (or maybe lets say 2.5 because you may not realistically discharge all your battery before the late night charge session). Could you create something to simplifies this down to a simple ration, similar to your rule of thumb?
Howdy Andy! You are absolutely right, and this is something I've been thinking about how best to include in the rule of thumb. It would require an extra piece of information about your battery size, as you mentioned, but then also another extra value indicating how much of your demand can be load shifted into the off-peak periods (and so doesn't then have to be covered by your battery). In principle this can be added to the rule of thumb but it's getting increasingly complicated and further away from my attempt at making it simple! I shall attempt to incorporate it into the "power user" version of the spreadsheet, for sure, along with a better strategy for the Flux tariffs, as those are also not really properly accounted for when generation drops low. There is always more work to be done.
@@TimAndKatsGreenWalk For proper accuracy, yeah, not just knowing what your total consumption is but _when_ you consume (how much can be shifted to off-peak) would be needed. For generation to consumption ratios that are not very large, it might be pretty reasonable to assume that you never draw from the grid at peak times though: such consumption would have to be non-shiftable _and_ have already drained my battery. For me, I'm pretty sure I never draw at peak times - or do so so infrequently that it doesn't affect the analysis.
@@TimAndKatsGreenWalk I've only got about 9.2kWh usable battery, but can easily consume 20-80kWh a day during winter. So I am no where near the 'battery can cover all your consumption' part of your Rule of Thumb.
@@AndrewSmithThomas yes, I originally intended this to only really be a Summer tool, in which case a typical battery would be enough to cover most people's daily demand. Sadly the Summer is long gone! I was hoisted by my own Picard!
You’re absolutely in control of when your car battery is charged *by*. Which is the control you actually want - particularly since Octopus give your whole house cheap power when the car charges. Thats often some extra hours here.
I have just switched to octopus go, I found your video very helpful in understanding all the tariffs, I can't get intelligent go for the same reasons. I have recently increased my battery from 7kwh to 12kwh and I am thinking of adding another 4.8kwh.
That's great, I'm glad I could help. I'd love just a little bit more battery capacity, maybe another 5kWh or so. We'd definitely be able to cover almost all of our Winter usage at off-peak rates then. If battery prices come down a bit more it'll become worthwhile, so maybe in the next year or two.
Got my EV a few weeks ago, charger installed yesterday and already on Intelligent. We've got 8.9KWp solar and 10 KWh battery but we also use a lot (average 17 KWh per day) of normal usage electricity (i.e. not the car or any heating). On most days our battery should last until 23:30 so I aim to get 95%+ of our consumption on the night rate so the calculation is obvious - which one has the best night rate? So I was delighted to get onto Intelligent. The only situation where I'd likely change this is if energy prices shoot up again and it's worth going back to Flux because we export an awful lot. Across 2023 we averaged better than 20p per unit for export and made a fortune. But while Flux export rates aren't much better than the Outgoing 15p there's no point.
I've just looked at Cosy and it's interesting to look ahead for if we do get a heat pump. It'd probably require a fair amount of maths and analysis! I'd have to look at how much was being used and balance that against getting another 5 KWh battery because that would save a lot as well.
Yes, indeed, as soon as you're unable to cover a good chunk of your usage with off-peak power the calculation gets a lot more complicated. I'm having a think about how I could incorporate that into a future version of the rule of thumb calculation but I think it will inevitably be more complicated as it'd involve entering your battery capacity and a few other things, but maybe that's not so bad.
@@TimAndKatsGreenWalk There's so many variables I don't envy you trying to boil it down into a relatively basic way of comparing them! My situation changes hugely as soon as the schools break up. It's half-term right now, by 7am the kids are usually up and have my projector and amplifier on to play Minecraft or Lego Avengers for about 4 hours which doubles our usage and on grey days there's little chance of solar covering it. I could ban them from my man cave but then they'd be grumpy kids. And grumpy kids makes for grumpy wife. And nobody wants that.
@@FlatToRentUK you're making the right decision, I'd say!
Need to do a new video, Octopus Go now compatible with the 15p export 🙂
I know, what timing! I put a community post out about that earlier today. I've already updated the values in the spreadsheet but I'll do a quick update video soon too.
@@TimAndKatsGreenWalkyes Go just got significantly better. Im on IGo but it can be a faff and its good to know that if i get fed up with it i can move to Go with little diminution, roughly £100/yr for me. (Essentially the difference between the off peak rate times however many kWh you use in a year)
@@Joe-lb8qn yup, similar to me.
Interesting Tim.
This confirms my choice to stick with Octopus Intelligent Go for now. This will be my 1st winter on OIG so it will be interesting to see how we perform with 19kWh of batteries this year vs 9.5kWh last year when we were on a standard Octopus rate. That said I still have a conflict between my batteries & export when our car is plugged in & Octopus do a Smart charge session outside of the normal 11.30pm-5.30am IOG cheap rate period (when I pause my battery discharge to allow the car to charge). Basically when Octopus send the signal the car is forced to charge, the inverter see's this as a load & supports the 7.5kW charger (Zappi) with 3.5kW of battery power. Essentially this drains the batteries to the car instead of exporting to the grid. The only solution that I can see is to have my system rewired to feed the car charger separately from the main consumer unit so the inverter cannot see the car charger as a house load. Too expensive to do so I'll just have to live with what I have for the time being.
This may be a point to bare in mind if Octopus finally approve your GE charger & car combo & you switch over to IOG in the future. That said with an all GE (inverter & Charger) system you may not have this issue as the inverter & charger should communicate with each other to prevent this issue.
Yes, I can see that would be annoying. As you say, we went for the GE EV charger on the assumption that we'd be able to charge the EV without discharging the home battery and that is indeed an option in the settings, so that was great. I just hope Octopus can get it integrated into IOG soon!
I went with direct car charging, just needed an additional Henley block, CT and consumer unit and cable. Definitely worth the small outlay to save the house batteries.
@@tebbo8324 👍 Humm. I have a spare CT & my consumer unit was replaced when I had the charger & solar installed. I also have a separate mini consumer unit installed that serves the PV system, Charger which has an integral meter. So, perhaps adding a Henley block & a bit of a re-wire is feasible without too much upheaval or cost. Add to the project list of "to do" & investigate list.
This is where you need automation…
I have home assistant monitor the charger, and tell the battery to charge when the car is charging.
I've got the car scheduled hours the same as the charger scheduled hours. If Octopus tries to charge it outside of the offpeak time then the car will block it. It's a shame because I'd like to have that option available especially as we want to use green energy when it's being generated. But draining my battery so it's empty for the evening doesn't work.
Interestingly (might be playing fast and loose with the word....) I asked a friend what happened to him in this situation and he doesn't have that problem. I'm friends with the guy who installed both our solar systems so I asked him and his install is different to mine. When his mains cable enters the house it hits his meter but then is split with one feed going to his main Fuse Board and onto the Solar Board, and the other side going to a Henley Board which connects to his Ohme charger. So the charger can only be supplied directly from the mains, it doesn't even know about the solar and battery. And vice versa, his solar app figures are completely oblivious to car charging. Whereas my charger is connected to my Solar Board so will make the usual priority choice of solar generation -> battery -> mains. I did wonder about having a Henley Board installed but it seemed like a lot of hassle to just be able to smart charge on the odd occasion Octopus make it available. We don't do huge miles in the EV anyway.
This was a helpful video, thanks. We have a similar set up; PV, battery, EV & Air to Air heating but cannot take advantage of Intelligent Go as we don't meet the compatibility criteria. We've been on the Agile tariff over the summer and into Autumn but definitely feel the rates are no longer proving beneficial, particularly where we would need to re-charge the battery around midday, prior to the peak period. We are therefore considering moving to either the Go or Cosy tariffs for the winter.
I like the idea of heating the house during the night but it's not advisable to keep turning heat pump compressors on and off, as it reduces their lifespan. They can end up consuming more power this way too, as they work harder to regulate from a 'cold start' as opposed to leaving them on to maintain a consistent ambient temperature. It may be better to programme the consoles to reduce the temperature of your house during the day, as opposed to switching them off entirely.
Yes, what I mean by heating the house overnight is boosting the heat pump so that it does more heating during the off-peak period, so that has to work less hard during the day. I don't mean turn the heat pump off entirely during the day. Usually the setback temperature is reduced overnight but what I'm suggesting is actually increasing it when the tariff rate is low, then using your usual setpoint temperature during the day. If you can exclude your bedroom from that then so much the better since you probably don't want to overheat your bedroom overnight.
@@TimAndKatsGreenWalk Nice one. We're managing not to have the bedroom consoles on at all at the moment, as it's still relatively mild. The downstairs consoles are maintaining the setpoint temp for the entire house but as the temperatures drop, I think we'll adopt this approach. Thanks.
Only have solar and 16kw battery so sticking with Octopus Flux. Still charging and discharging at low and peak times. Will be interested to see how it looks at end of the winter period. So far even with low solar generation my stored overnight battery export seems to be cancelling out my overnight import costs.
I do need to implement a different "optimum" strategy for Flux and IOF, as I don't think they're quite right for either of the existing strategies in my rule of thumb for the Winter.
Spoke to Octopus and Givenergy people at Everything Electric Farnborough. Both blamed each other for the lack of progress with integration of the EVSE. Not very promising unfortunately, but hopefully once they work it out it will all happen quickly.
It's very frustrating. I hope they can sort it out sooner rather than later.
Next Drive v4, charge batteries and run heatpump from midnight to 7am, thats 7 hours at 6.7p, use the full batteries durring the day, if its a sunny day then export at 16.5p. At the end of the day then dump the entire battery at 16.5p. Approx profit is about £100 a month during winter depending on he size of the battery. EV is not required if you have solar and batteries
I am aware: ruclips.net/video/uJxTgIWX4NA/видео.html
Can't really do the arbitrage thing if you've got heating to run though.
Interesting video thank you. I am on a FIT agreement getting an index linked payment of about 25p production plus 7p on assumed 50%export although because of a 9.6 Kwh battery export is actually nearer 15%. This will continue for another 8 years. I am on Octopus Go with a production of about 3400 Kwh and usage of about 3200 KWh per annum. This type of scenario is seldom covered in videos but I think I am on the best tarrif and would not benefit from switching to another export system. Basically my electricity is self funded now because of previous investment but when I change to an ASHP from oil and go down the hybrid diesel car route a rethink may be needed!
Interestingly the export rate for Go has recently been increased to 15p/kWh up from 8. I don't know if that would change your decision but it could make a difference to you in the Summer when you'd likely export a good chunk of your generation. Apparently it's possible to give up the deemed export portion of your FIT while keeping the generation part, which is handy.
My ratio for the last 12 months on IOF is 1.4. No EV + gas heating. Trying agile for the winter, will be interesting to see how it compares to last year, average unit rate etc.
Agile is definitely worth a try. It's not something I've tried out myself yet but maybe one day.
Really helpful video thanks! You must face a big trade off with these videos between simplicity and covering as many potential scenarios as possible.
I have a small battery and no EV. Am currently on agile but this made me think the cosy tariff is worth considering. As i see it the downsides are (a) lots of battery cycles will inevitably knacker the battery faster. Atm i do 1 cycle a day so increasing to 3 would be a big shift, (b) heat pump efficiency will take a bit of a hit if running the heat pump for fewer hours but 'hotter' to overheat the house during cheap periods. This strategy probably gets worse when its very cold and heat loss is higher.
So it's not necessarily a no brainer. Agile has been a bit rubbish recently with lots of still, cloudy days but I'll give it a few more months and see what the rate averages out at. A slightly worse average rate than cosy might be outweighed by round trip losses from constantly charging and discharging the battery with cosy
Yes, it does get complicated very fast, it's a bit of a nightmare! The one thing I forgot to mention regarding Cosy is that not all battery systems allow you to set up multiple scheduled charge slots, which would make it annoying to manage. But if you can it's a viable option. I wouldn't worry too much about battery lifetime though; by the time the battery has reached the end of its useful life replacements will be cheaper and better, even if you reach that end of life sooner than you would by cycling more often.
We used Cosy from mid-Nov to mid-Feb last winter. Our GivEnergy grid-tied inverter only allows one programmed charging period, so I just reprogrammed it twice a day. It would have to be 3x /day now though, which is more of a pain. But the prices probably make it worthwhile financially. I reckon we would be paying on average 12.5p/kWh on Cosy, and we're averaging 11.9p/kWh on Go at the moment, so not yet worth it for us, but close.
One thing that makes the picture muddier is if you are signed up for Octopus Saving Sessions, where they pay you for every kWh of electricity you cut from your typical use for an hour or so (usually somewhere around 5-7pm), on a day where there's high demand and low renewable supply. The winter before last, we were on Go, and got paid £75 over the course of the winter for joining them. Last winter, we went for a scheme from GivEnergy, where at the same times, they draw energy out of your battery and pay you more for it, having automatically topped it up just before. It's less hassle, but it didn't work well with Cosy because it stopped us charging during the afternoon cheap rate, then forced a charge at peak rate. We still made a profit out of each session, but our total for the winter was only £16.20. So I now need to work out whether Cosy will save us more than £60 over 2 months, or we might be better off with Go and Saving Sessions
One thing to bear in mind is that a 'charging cycle refers to a complete charge from empty to full, so if you charge from 40% to 60% five times, that's one cycle. For us, on Cosy, we could charge our battery by 75% in the 3 hour periods and 50% in the 2 hour period, so if we use it all, then over the three charging periods, we are doing 2 cycles. I would expect the battery retain reasonable capacity for a good 15 years at that rate (and of course, it only cycles that much in winter), but it will have paid for itself within 8 years. And it won't be defunct after 15 years, it'll just have a reduced capacity.
at about 5:15 you say GivEnergy EV charger is not compatible with IOG but I just ran my very similar system including that same charger through Octopus's compatibility page and it says it should work.
It's not showing up in the app when you get the charger section. Is it perhaps your EV that is compatible rather than the charger? It can be either.
Yup, I just checked and neither our Fiat 500e nor the GE EV charger are compatible when I check.
Thanks for the helpful video although my generation/consumption ratios range from around 0.5 in December to about 4 in June. However many of these Octopus smart tariffs are not available to those of us who just have solar and batteries, or an incompatible inverter. Also, how does Octopus Agile or Octopus Tracker compare with your favourite tariff(s)?
By all means grab a copy of the spreadsheet and add in whatever tariff you choose. Agile is tricky though because it varies so much, so you'd have to make some assumptions as to the average "off-peak" rate and whether that's likely to continue into the future or not.
I dont have an EV so im on Cosy Import and Fixed export, I also use Predbat which predicts my usage and manages my charge/discharge/import/export. I'll probably move to Agile again at some point over the winter when the average import price dips below Cosy's, that's when Predbat really comes into its own.
Very nice. Home automation isn't something I'm keen to get involved with but I can see how useful it is for this sort of thing, especially once you introduce Agile into the mix.
@@TimAndKatsGreenWalk Predbat is interesting, it knows when the cheap periods are (even the Intelligent Go ones that change) which is clever.
I run Home Assistant too, I haven't really automated anything but I do find controlling the AC units easier with HA than the Toshiba app, and scheduling is much better.
As I can't get IOG, sticking with Agile - no doubt it'll be higher some days, and cheaper on others - but it's variability makes modelling harder unless basing on historic data.
At some point I'll see if I can add in Agile to this, but as you say it's very variable, which makes that tricky.
@@TimAndKatsGreenWalk I added Agile to your sheet just by taking the average import price, basic I know but it gives me an idea on when to move to/from Agile
@@symonchester yup, that's how I would have done it, probably. It's very difficult to tell if it'll continue with those averages into the future though, which is why I was reluctant to include it.
Hi, great video and much appreciated. Im about to have my first system installed in two weeks, its all Givenergy with 7.2kw system 9.6 battery and a car charger. Would the Go or intelligent Go still hold true if you factor in charging the car through the night? I assume it would, but being a newbie i thought id check. Many thanks
Yes, in fact this assumes all your EV charging is done at the off-peak rate, so setting up to charge overnight is the right thing to do (just include that in your total consumption values). Good luck with your install, I hope it all goes smoothly!
@@gregcarnall9097 absolutely - but if GivEnergy is smart enough to charge the battery when the car is charging… then you can really benefit from extra half hours
I will add my view, indeed IOG is a great tariff, but atvthe end of October my 15kwh battery had depleted at about 9pm. So roll on cosy and my new ability to schedule 3 charge sessions. As you are good at speead sheets and a great understanding of energy tariff i think there is a very useful tool tobbe made. Breakdown 4 levels of heat loss. 3 , 5 8 and 12 . Then have four battery sizes 5, 10, 15 and 20. Peope could then select house size or in this case heat loss and then battery size. I think like in my case when youbhave a heat loss of nearly 8kw and a fairly large 15kw battery it can only be cosy that works. You also have the advantage of during yhe day when the battery is full the excess goes tobthe grid for my 15p export. Not a massive difference to my 12 import but no risk, ifbits sunny i get a discount if not its 12p then.
Indeed, I made the point in the video that if you're unable to cover a good fraction of your Winter usage with your battery using Go/IOG then Cosy would be a good option. The tool you're talking about is something I'm actively considering how best to tackle, but these things take time to do right so I can't promise anything. Keep an eye on the channel and you never know 😉
@@TimAndKatsGreenWalk cost cheap rate is ~10p, but you can still get 15p export. So it could end up being a good deal, though that could also end up being a lot of charge cycles!
@@JohnR31415 this is true but this is what the battery is for. I buy at 11.6p on cosy and sell at 15p. The differences is only small so I don't mind and gamble on full charge my battery and sell the small amount I don't use. Time can model the scenario using his data and add a simple multipliers to the heat load to simulate high heat loss. Air to air and water systems offer similar scop,s
My Cosy rate is 12.65p. You could use Agile export with this and export between 4pm and 7pm at 20p +.
you might need to do another update, with Go you can now get the 15p export tariff.
Way ahead of you 😉 ruclips.net/video/ORMSqfIUhuQ/видео.html
I'm also waiting for the Intelligent Octopus Flux, as I have a Tesla Battery, so I can only get Flux. The Integration for that also has been set-up yet, but I've heard that Tesla and Octopus are working together. I'm still not sure if that will be better for me than Flux I'm on at the moment. Also with the Saving Sessions I'm again hoping this will help this winter, as I've gone for a 2nd Tesla Battery. Maybe I should have gone for a Heat Pump instead?
Well, if you look at the rule of thumb chart for the export strategy you'll see that Intelligent Flux is only better than Flux if you have a generation / consumption ratio higher than about 1.25 (that's the whole point of this chart!). If you know your typical generation and consumption values you'll be able to work out which is better for you for any given month. I'd certainly consider switching to Go/IOG over the Winter instead though, if you can. Especially with such a large amount of battery storage available to you.
@@TimAndKatsGreenWalk Yes agreed. Just need to get the EV now :) As I don't think I can get that tariff.
Who did you use for your air to air system? I also live in Gloucestershire and want to compare air to air to air to water.
We used a local chap with a business called Just Chillin' in Stroud. A Google search should bring up his website.
Cosy seems a no brainer for anyone with batteries.. do you need to prove you have a heat pump? (currently on agile 16kw battery but use around 30 -40kw in a day only have granny charger for car)
It depends on the size of your batteries relative to your usage, as I mentioned in the video. If your battery is significantly smaller than your daily usage then Cosy can be a good option, yes. But for us we only use more than our battery can supply for a few weeks a year, so the lower off-peak rate on IOG is likely to win out over Cosy when taking a full Winter into account. Watch my battery sizing video to show how I was able to reduce our peak demand to almost zero once I adopted the heating overnight strategy: ruclips.net/video/_qysulne5g0/видео.html
As for proving you have a heat pump, Octopus may ask for the MCS certificate but might not: octopus.energy/smart/cosy-octopus/
@@TimAndKatsGreenWalk yes.. looks like they actively check for installs (hmm could I ninja up and go and grab the serial number from a random unit down the street...) . grr That would be ideal for us. Pretty much guarantee a 99 quid a month electric bill over winter till the sun shines again. Where as we are around 150 on agile.
My understanding there was a legislative change allowing the entry of households to buy and sell their power on the spot energy markets. I’ve not seen any commercial offerings allowing this access yet, has anyone else please?
That's effectively what Octopus Agile is (although not quite how you describe, it's just done via the tariff itself). I suspect you're thinking of the Settlement Reform proposal, but that's aiming to make it easier for energy suppliers to offer tariffs, such as Agile, that follow the spot market, rather than actually allowing domestic customers to buy and sell power direct to the spot market themselves. I doubt that'll ever be a thing individual households could do. www.ofgem.gov.uk/energy-policy-and-regulation/policy-and-regulatory-programmes/electricity-settlement-reform
Does that still apply if you have a heat pump as well as electric car , solar with battery’s I’m on cosy
I mention that in the video. It depends on your battery size and whether or not you can cover most of your heating needs using your battery.
I have solar and a heat pump. I've switched to Octopus Cosy. I notice that right now -in the peak period- the house is using electricity from the battery and from the grid. Is there anyway to set a preference for the battery to be used during the peak period, so that it can then charge during the cheap dips?
That entirely depends on your battery system. You'd have to look into your specific settings. For our system we can set a timed charge period, in which case the battery will charge during that time and everything else will use the grid while the battery is charging. Then at all other times the battery is used to support the house (it's called Eco mode in my settings). I think I can only set up one scheduled charge period, however, so for the other two periods I'd need to do that manually (by setting an alarm on my phone and then manually setting the battery to charge, for example).
@@TimAndKatsGreenWalk Thanks Tim. I've found on the GivEnergy web remote control (go to My Inverter and look in the top right hand corner) the option to set up to 10 charge/discharge times. I've set three times to charge. I've yet to set discharge times - I presume I should set one between 16:00 and 19:00?
@@NigelPJ generally a battery in the appropriate mode should do that - if your using more power than the inverter can handle then you have to import to make up the difference.
Opted for cosy - first winter on ASHP, no EV. Running a Tesla 13.5kwh battery and 5kwh solar. At the moment the highest use per day is 22kwh running the heat pump off the outside temperature which seems to be the most efficient way of running it? Solar is still running the system on sunny days at the end of October which was a surprise. Just feel that with the ability to charge the battery 3 times and also running the house during the 8 hours of off peak (12p/kwh) this must be the cheapest way of doing things? Love drilling down into the geekery of the system so will try to work out other tariffs over winter ready for next winter.
Hi. Where does Economy 7 fit into these scenarios for winter ?
Take a copy of the spreadsheet and add in the tariff rates for whatever tariff you like, then you can see how it compares to the others. But looking at the off-peak rates for Eco 7 it looks slightly better than Flux (except I don't think you can get as good an export rate - in fact it's not clear if you can get anything other than the SEG with the Eco 7 import tariff), but worse than all the others, so Go, IOG, and Cosy are all better in the Winter, and Flux is better in the Summer due to the better export rates.
I went live with an 8.4kwhp solar and 5.2kwh GivEnergy battery system on the 10th October and I’m on IOF as I don’t have an EV yet. For the 21.5 days of October my ratio is 1.42, if I look at the whole time I’ve been live my ratio 1.22. I’m on IOF but you said to ignore it as a tariff for the Winter/Self consumption chart. Given my potential ratio and no EV isn’t IOF my best tariff option?
Well, regular Flux would be better than IOF for the Winter as it has an off-peak period that you can use to charge your battery cheaper than on IOF. Use the chart and find the lowest line for a particular month, don't use your overall ratio as that will change dramatically over the year, getting much lower over the Winter. The reason I said ignore IOF on the self consumption chart is that you can't operate your system using the self consumption strategy when Octopus are controlling your battery for you. They will deliberately force export your battery in the evening, which is not what you'd do with self consumption. Use the export chart instead. IOF might well be better for you in the Summer but it's not a great tariff for the Winter.
I'm on octopus go. I would like to be on octopus intelligent go but it does not support my current setup.
I had three phase installed.
I then built a three-phase off-grid grid tide system with 82 KW of battery.
My battery pack cost £12600
Each victron inverter was about 3000 (3x)
I had to upgrade to three-phase power which cost me £2,000.
I pull from the grid at 12:30 at night at about 45 kW. I'm normally fully charged within about 2 hours.
I have a high base load of 1.2 kilowatts.
I'm only using between 20% and 80% battery which is up to 90% in winter.
I charge the battery up and then disconnect from the grid automatically.
I only have 6 KW of solar. Which produces around 5 megawatts a year.
I have a plan for another 20 kW of solar. For rule of thumb on one phase you can 10 kW of solar.
I've been thinking about going down the water to air heat pump. But the costs were over £25,000 including the subsidy of 7000.
I'm thinking of going down the air conditioning route. I think on average about £3,000 per unit worst case.
I may look at adding more battery the goal of 120 kWh
Blimey, that's a heck of a system, very impressive. I'd love to upgrade to three phase one day.
I use Octopus Cozy in winter, since i'm using lots of electricity and I can charge up cheaply (12.5p/kwh inc vat, 11.88p/kwh exc vat) 3 times a day. Solar generation in Bristol is nonexistent at the minute with so much cloud everywhere, especially where I live. I have 10.5KWp of solar and generated 1KWh today, 1.9KWh yesterday and so on - hardly enough to make a free brew...and things will only get worse up until Christmas
I've had dreadful generation the last couple of days too.
@TimAndKatsGreenWalk It's been more than a few days for me...more like a month or more with the exception of a few freak days...when the sun does eventually make an appearance neighbours will think it's a sign of the 2nd coming or something...- we sure won't recognise it....
@@rbee3936I've forgotten what the sun looks like it seems so long since we had any decent generation 😔
No mention of Agile?
No indeed. By all means add it to your own copy of the spreadsheet in whatever way you believe is appropriate. It's too variable and unpredictable to include, in my opinion, as it's unlikely to remain consistent over any length of time. But don't let me stop you if you want to add it yourself.
So why don’t you move to EoNext where you get 6.7p kW from Midnight to 0700?
Because I prefer Octopus as a supplier. And it's not worth switching for a relatively small saving.
I have 2.6kwh of solar, 14.4kw batteries, ASHP, and EV. I have an ohme charger which is compatible with Intelligent Go, but being on that tariff would cause my battery to deplete when charging the EV outside of off-peak times, which I absolutely don't want! So I am sadly still on basic Octopus Go.
Yes, that's annoying. There are ways to prevent your battery discharging into your EV but it requires some rewiring of various things, which might be too much of a pain. Our EV charger prevents our battery discharging into the car as both are GivEnergy, but sadly that also prevents us from getting IOG, so we're also stuck with regular Go!
I have 13.35kWp of solar, 13.5kWh of battery, Air-Air heatpumps (18kW between the two multisplits). Both EV chargers are Zappis and we're on IOG. The battery is a Tesla.
I use home assistant to control if the battery charges from grid or discharges, based on the current electricity price.
When IOG triggers a smart charge, it drops the whole house rate to 7p/kWh, and I immediately start importing everything I can - the battery charges, the 2nd zappi starts charging, the ASHP comes on and heats the house to a comfortable temperature (at 5.1COP!! so like 1.4p/kWh of heat!!). I never charge the cars from the battery. In fact I gain significantly due to the "extra" offpeak hours.
Then when HASS detects the rate has gone back up, it stops importing and goes back to normal behaviour.
@@sheilathepotter6636 either wire it outside the house or get it automated so that the house battery benefits from any additional charge slots.
I've had 3.5kw of solar for 13 years, so I have done well with FIT payments. I'm buying extra solar and 27kw Powewall. I have ASHP and getting air to air as well. No EV, so I am thinking about Cosy with Agile export. I could fully charge the battery at 12.65p kw and then export most of this between 4pm and 7pm. It looks like I may get 20p+ for this. I will have along payback time so it will all help. Does this strategy make sense?
That could certainly work, as long as you're able to charge your batteries during the multiple off-peak periods. Not many systems allow multiple scheduled charges per day, so that's worth checking.
Good point. I will check. Thanks
Just looked at a video on the Powerwall app and you can set multiple time periods for each tarrif rate. You don't specifically tell the battery to charge but apparently the app should work it out, as it knows to charge at the cheapest rate.
The rules for (Intelligent) Go is that you need to have an EV. Similarly for Cosy you need a Heat Pump. Do you have advice for those of us with just PV and battery?
Currently on Agile, managed by Predbat btw
Yup, if you ignore the lines on the chart for tariffs you can't get then the next best one is regular Flux for the Winter. It's not an ideal solution but it's better than the standard Flexible tariff, for sure.
IO Go is 7p and you also get the extra hour
Yup, the extra hour can be handy.
And extra hours when the car charges, for instance, in the 12-2pm “dip” in price ;)
@@JohnR31415 Yes if I know I don't need the car until say 11 or even midday, I set the app to those times and quite often I get off-peak slots between 0530 and 1100 - which is great (my 7 billion cups of tea of a morning haha)
Can you make the colours on the legend of the chart bigger / easier to see? Not so easy to spot the difference- sorry to be a pedant
It doesn't appear that I can, no, sorry about that. That's not an option in the chart settings available to me in gsheets, so far as I can see (the font size is adjustable but not the size of the coloured bars, annoyingly). If you grab a copy of the spreadsheet you can change the colours to whatever you prefer, however, which might help.
On the chart editor under the Customize tab there is a Legend option.
Legend Font size is in there (and defaults to Auto).
In each series you can also specify a colour - just need to find a colourblind friendly set for the count of lines you’re using.
Can I ask a question that I should have asked before the summer. I just presumed, I’m sure somebody will know the answer. I have two separate installs. The first 3.5Kw of solar was installed under FIT. The second 4Kw with battery (8Kw Give Energy) car charger and diverter (myenergi). I claim the FIT. Can I also claim for export (I’m on intelligent Go), I presumed I couldn’t because I’m claiming FIT
The best thing to do would be to give up the "deemed export" part of your FIT and then get a proper export tariff for your full export. The deemed export is a relatively small part of the FIT and you'd almost certainly do better with a proper export tariff especially given you've extended your system. Call your FIT provider to confirm but I believe you will still be able to claim your generation FIT payments (which is the really good bit) even if you give up your deemed export.
@@TimAndKatsGreenWalk Glad I reread the comments before posing a similar question. I enquired about this when we had our battery and second solar array install, and was told we would lose the FiT if we did this. Perhaps I was misinformed, I hope so. If you can give up the deemed export and get a proper export tariff without losing the FiT generation payments, that would change everything for us.
Tim, do you have a source that suggested to you this was possible?
@@markdearden1697 I've had a few comments in the past from others on the FIT that managed to do this, so it must be possible.
@@TimAndKatsGreenWalk Good to know. I'll try asking Octopus about this. Perhaps the stumbling block is that l get my FiT payments from a different supplier.
@@markdearden1697 I'm sure they should be able to handle that one way or another. Yeah, definitely worth speaking to Octopus about it. I seem to remember there being something about FIT payments in their Flux FAQs, I'll see if I can find it.
Hello old friend. I'm on Cosy having done some pretty crude calculations to compare tariffs. Your comments have made me think that there is potentially a ration of battery size to consumption that would produce a rule of thumb of when Cosy - or other tariffs are better.
Cosy is great because you get to charge your battery at the cheap rate 3 times: 2x3 hours and 1x2 hours. We could probably make some crude assumption about being able to perfectly charge and perfectly discharge your battery: so for most tariffs you get to charge once only, if your consumption matches your battery size you get all your power at the lowest rate. As your consumption goes above your battery rate, we assume you use at the day (not peak) rate. Cosy has a massive advantage, because you get to charge 3 times (or maybe lets say 2.5 because you may not realistically discharge all your battery before the late night charge session). Could you create something to simplifies this down to a simple ration, similar to your rule of thumb?
Howdy Andy! You are absolutely right, and this is something I've been thinking about how best to include in the rule of thumb. It would require an extra piece of information about your battery size, as you mentioned, but then also another extra value indicating how much of your demand can be load shifted into the off-peak periods (and so doesn't then have to be covered by your battery). In principle this can be added to the rule of thumb but it's getting increasingly complicated and further away from my attempt at making it simple! I shall attempt to incorporate it into the "power user" version of the spreadsheet, for sure, along with a better strategy for the Flux tariffs, as those are also not really properly accounted for when generation drops low. There is always more work to be done.
@@TimAndKatsGreenWalk For proper accuracy, yeah, not just knowing what your total consumption is but _when_ you consume (how much can be shifted to off-peak) would be needed. For generation to consumption ratios that are not very large, it might be pretty reasonable to assume that you never draw from the grid at peak times though: such consumption would have to be non-shiftable _and_ have already drained my battery. For me, I'm pretty sure I never draw at peak times - or do so so infrequently that it doesn't affect the analysis.
@@TimAndKatsGreenWalk I've only got about 9.2kWh usable battery, but can easily consume 20-80kWh a day during winter. So I am no where near the 'battery can cover all your consumption' part of your Rule of Thumb.
@@AndrewSmithThomas yes, I originally intended this to only really be a Summer tool, in which case a typical battery would be enough to cover most people's daily demand. Sadly the Summer is long gone! I was hoisted by my own Picard!
@@TimAndKatsGreenWalk Well keep up with it; Klingon for dear life, mate.
Unless, like me, you are a bit of a control freak and don't like the idea of third parties deciding when your battery charges and discharges! 😱
Intelligent Go doesn't control your batteries, you're thinking of Intelligent Flux.
@@TimAndKatsGreenWalkcar battery?
@@MrNilOrange they don't discharge your car battery. Based on your comment I interpreted it as you meaning the home battery.
You’re absolutely in control of when your car battery is charged *by*.
Which is the control you actually want - particularly since Octopus give your whole house cheap power when the car charges. Thats often some extra hours here.