Lots of good info here if you can DIY
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Solar Panels UK - is it worth it?
- Thread starter jdwuk
- Start date
Lots of good info here if you can DIY
so according to the CS at Eon, they don’t have any installers in my area - slough/windsor. You’d think there would be loads. Assume they subcontract but you can’t just sit there as a major national energy supplier - pushing Solar/battery on their website and just shrug ‘no installers sorry guv’ ffs.
I’ve asked for it to be escalated and for them to get back to me. Get someone from a little further out. stupid. Want to get this sorted before the generation starts ramping up
I’ve asked for it to be escalated and for them to get back to me. Get someone from a little further out. stupid. Want to get this sorted before the generation starts ramping up
But to make electricity cheap enough to justify replacing a gas boiler with a heatpump there needs to be cheap electricity at least once a day.
WannabeOwner
Well-Known Member
I think that's likely (just speculating ...)
When Consumption is less than (available) Production then there is surplus and price can drop - particularly when Consumption is less than the Production which cannot be turned off - Wind and Solar, and maybe some Nuclear, and anything else that has to be left spinning for "a while" ... like, errmm, coal!
That's going to be a period during most days ...
Heat Pump users will get periods of No sun / No wind, in winter, and pay through the nose ... but that will be a week or so each year - and during periods when there is loads of wind they will get cheap price. Maybe swings and roundabouts (but I am guessing ...)
For anyone with a well insulated house and thus able to run heating "a degree high" during cheap periods, and a "degree low" during expensive periods that would work out OK. My heating only comes on for a short period each day 'coz house doesn't leak heat and if I heated in middle-of-night rather than during-the-day it wouldn't make a noticeable difference... but 99% of UK housing stock is not sufficiently well insulated ...
The other thing that occurs to me is that all battery owners will fill-their-boots when price is low ... which will make it easier to sell the cheaper electricity, and I guess?? the price won't fall as low (as if there were not enough takers). But when that is the case maybe Peak price won't be horrendously high either because battery owners will be incentivised to export to cover the short fall ... again moderating the Peak that the price will rise too.
But a week of No Wind will drain all domestic battery users gaming the system ...
My 2 penneth:
With 10.9kW PV and 2 Powerwalls, I use about 2000 kWh off peak and less than 70 kWh peak in a year. Quite a bit of the peak is down to a SMETS1 meter sucking in power when it shouldn’t.
I’m not advocating Powerwalls above anything else, but they have worked well. I do know one guy who has had lots of trouble with his SE setup; the batteries shut down randomly and the panels do similarly on a sunny day and so on. I have some panels with SE optimisers and SE inverter. No trouble with them at all.
What I will say is generation in summer and winter are two extremes; worst winter day 100 wh, best summer day 65 kWh !!
we aren’t big users, just over 9000 kWh per annum. Adding a Powerwall is pointless as I can go 48 hours on two and adding more PV, if I had space, would benefit winter to a degree but be wasted in summer.
Perhaps one day there will be system where we can deposit it in the grid in summer and claw it back in winter for nowt! Dream on…
With 10.9kW PV and 2 Powerwalls, I use about 2000 kWh off peak and less than 70 kWh peak in a year. Quite a bit of the peak is down to a SMETS1 meter sucking in power when it shouldn’t.
I’m not advocating Powerwalls above anything else, but they have worked well. I do know one guy who has had lots of trouble with his SE setup; the batteries shut down randomly and the panels do similarly on a sunny day and so on. I have some panels with SE optimisers and SE inverter. No trouble with them at all.
What I will say is generation in summer and winter are two extremes; worst winter day 100 wh, best summer day 65 kWh !!
we aren’t big users, just over 9000 kWh per annum. Adding a Powerwall is pointless as I can go 48 hours on two and adding more PV, if I had space, would benefit winter to a degree but be wasted in summer.
Perhaps one day there will be system where we can deposit it in the grid in summer and claw it back in winter for nowt! Dream on…
My 2 penneth:
With 10.9kW PV and 2 Powerwalls, I use about 2000 kWh off peak and less than 70 kWh peak in a year. Quite a bit of the peak is down to a SMETS1 meter sucking in power when it shouldn’t.
I’m not advocating Powerwalls above anything else, but they have worked well. I do know one guy who has had lots of trouble with his SE setup; the batteries shut down randomly and the panels do similarly on a sunny day and so on. I have some panels with SE optimisers and SE inverter. No trouble with them at all.
What I will say is generation in summer and winter are two extremes; worst winter day 100 wh, best summer day 65 kWh !!
we aren’t big users, just over 9000 kWh per annum. Adding a Powerwall is pointless as I can go 48 hours on two and adding more PV, if I had space, would benefit winter to a degree but be wasted in summer.
Perhaps one day there will be system where we can deposit it in the grid in summer and claw it back in winter for nowt! Dream on…
sounds good but I’d guess the average reasonable size in the UK is more like half that - 5kw solar (3.68 inverter) and maybe 10kwh storage? Even that might be optimistic.
in summer that may still be plenty but would increase the deficit in winter?
A lot depends on panel orientation and shading. I’m surrounded by pretty tall trees that have no effect in summer but cause shade in winter.
Not having trees would double my winter gen.
However, the trees did a grand job providing shade in the hot weather. The tallest ones got a reprieve! We pollarded 5 out of 13.
But you are right, most domestic setups are a good deal smaller than mine. None the less, they are worth having.
WannabeOwner
Well-Known Member
I assumed that until a recent discussion which caused me to check PVWatts for North facing panels.
In Winter, yeah only 40% of South - but of course even South is "not much" in Winter
But in Summer North will do close to 80% of South, and start earlier / finish later than South (which is helpful in terms of being able to use it for normal household activities)
Pete UK
Member
There was…. It was called the Tesla Energy Plan !Perhaps one day there will be system where we can deposit it in the grid in summer and claw it back in winter for nowt! Dream on…
But alas - no more.
ElectricPolice
Member
Pretty much my scenario, 4.66kW solar PV, south facing, 3.68kW hybrid inverter and 5x 2.6kW batteries.
Had it 2 years and every day is a game of roulette, fully charge batteries when forecast is cloudy and see how long it lasts. Some days the sun comes out and I’ll bung on a wash & dry cycle. Other days if it remains dull I’ll just let the batteries charge up as much as they can in the day and see how long it lasts into the evening. The balance is trying not to export too much versus maxing the battery capacity so you don’t run out in the evening before cheap rate kicks back in. We time shift everything so between 80-90% off peak usage, washing, drying, charging etc.. even rads throughout the house overnight to avoid central heating in the morning.
For example, today, battery charged to 82% on IO overnight. Drained down during the day in an empty house. Only 3.9kW of solar today so flat lined house usage and minor charge mid afternoon. Come this evening with a family dinner and multiple appliances turned on the rest got used. We’d run dry by 8pm and were consuming from the grid.
In the summer it’s a different game, if we get to 5 or 6pm on 99% battery we’re sorted through the night. Maybe a 1h top up before the end of IO schedule to cover the window before the sun comes up?
I wouldn’t over think it, I bought 2 batteries originally which was okay but after first winter decided I wanted a few more as they were pretty much drained by midday. Now I can usually last until end of peak time 7-8pm, in the worst case scenario, if I charge fully overnight.
PITA
Model 3 Performance
We've got two Powerwalls and during Winter ideally need three... on Octopus Go.
But with the new Intelligent Octopus tariff extending cheap rate to at least 6 hours (11:30 - 05:30)... it means the Powerwalls only have to bridge 18 hours now (not 20 hours).
In addition to this, if Intelligent Octopus give me an additional cheap rate period, we can boost charge the Powerwalls manually at 10kW, during those periods which would be excellent news for an extended top up.
Two Powerwalls and Intelligent Octopus might be the sweet spot for us.
But with the new Intelligent Octopus tariff extending cheap rate to at least 6 hours (11:30 - 05:30)... it means the Powerwalls only have to bridge 18 hours now (not 20 hours).
In addition to this, if Intelligent Octopus give me an additional cheap rate period, we can boost charge the Powerwalls manually at 10kW, during those periods which would be excellent news for an extended top up.
Two Powerwalls and Intelligent Octopus might be the sweet spot for us.
phil4
Member
Yes, late last year, Tesla cancelled all orders and have since put the prices up. Of course it wouldn't surprise me if the installers due to "cost of living" have also tacked on some extra to Tesla's increase too.
Pete UK
Member
Hi,
I think you’ve hit the nail on the head there.
This is the system and modus operandi I am looking to achieve. Without breaking the bank though. The battery storage is the key to saving the most, along with a good off peak plan. That said, if I can save £3,500+ or so a year on my elec bills, I’d be happy to spend up to 10x that as an up front investment.
For my situation; I’m using 19,000kW pa.
4,500 on the car,
14,500 is the house.
Currently that’s £6,650pa all at 35p/kW;
45kW a day house,
7kW a day car.
Currently it isn’t worth me switching to a cheap rate off peak plan, because the house would use more at the expensive on-peak rate, than I’d save charging the car off peak!
Proposed system;
9-11.5kW (generating 7,000pa), 30kW battery storage. (Swapping to Intelligent Octopus)
So new system would be;
7,000kW free from the solar,
4,500kW at 10p for the car
7,500kW at 10p from the batteries or 44p grid at peak (Assuming half at each rate to allow for winter use where I’m 15-30kW short on battery storage).
That could potentially bring my bills down to £2,475 ish per year. Or £206pm. That’s £4,175 pa less. That’s a lot !
Bills could be down to £1,200pa (if I had 40kW - 50kW storage!)
- and Yes I am aware there are a lot of other factors and it’s not that simple !
Problem I have with my quotes so far is the batteries - finding an installer that uses and can get ones that charge up at 10kW/hr and with a decent interface (phone app). And that isn’t adding a massive premium for the system and components.
I recokon that I need batteries that charge at 10kW because the IO plan might not always be there, so might be down to a shorter window in the future. (Just like the TEP vaporised!). Plus the car might be charging at the same time !
What system components have you got and what’s the charging rate of your batteries?
I like the Powerwall and Solar edge systems. Time scales and price are a sight problem though.
Anyone got any other more cost effective battery suggestions? Ones that are easy to manage and can charge at 10kW?
Thanks in advance.
RedMod3
Member
Just cranked the numbers for February. Last year our bill was for £198, but this year with two Powerwalls it dropped to £95, which was higher than I had wanted, but after our 3rd PW is approved and installed, we should use even less peak power (Feb 2023 - 188kW peak, 1178kW off peak).
After taking in the FIT rebate due of £49, our cost is £46.
Then deduct the Government contribution of £67, we are in profit by £21 with the added bonus of a £50 referral bonus next month. These figures include our EV charging costs.
PWs and Solar rock.
After taking in the FIT rebate due of £49, our cost is £46.
Then deduct the Government contribution of £67, we are in profit by £21 with the added bonus of a £50 referral bonus next month. These figures include our EV charging costs.
PWs and Solar rock.
