That may still be "working" under the previous rule that VAT would be at 5% if it was a solar install (or included solar) and had more than 40% of the total cost as labour (or something like that), just now it's 0% instead of 5%.
Solar panels and battery - any real world reccomendations?
- Thread starter GinG
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Soldato
Interesting to see so many people now looking at solar, I had my neighbour to the rear asking me all about it yesterday evening, yet when I had it installed I heard him comment to his wife in his own garden what a waste of time and money it was, he didn't know I was there obviously. 
I just checked and the 0% rate should also be on the battery if installed with solar, but clarity of battery only installs is still somewhat vague. I also tried to find out if 0% is on product bought commercially/privately but again there is no clarity on that either. Frustrating, as I want to add another battery ASAP.
I just checked and the 0% rate should also be on the battery if installed with solar, but clarity of battery only installs is still somewhat vague. I also tried to find out if 0% is on product bought commercially/privately but again there is no clarity on that either. Frustrating, as I want to add another battery ASAP.
LolInteresting to see so many people now looking at solar, I had my neighbour to the rear asking me all about it yesterday evening, yet when I had it installed I heard him comment to his wife in his own garden what a waste of time and money it was, he didn't know I was there obviously.
I really want it myself, but just seems unwise at the minute as we will be getting an extension done in a couple of years and may get the roof redone.
Soldato
We have solar rated 6kwh + powerwall and honestly hand on heart, it’s the best decision I’ve made.
Mind if I ask your rough total install cost? I'd love a Powerwall but they seem to have a premium, and also not sure I'd actually need the whole 15kWh capacity!
Deleted member 651465
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Deleted member 651465
Capacity on the powerwall is 13.5kWh and there will be a new version (V3) out soon with a greater peak output. I'd wait if you're on the fence.
Yea I doubt we'd be able to afford it but we'll see
estimating I'll use about 2500kWh on the day rate so average of 6.85kWh/day so wouldn't even need the 13.5kWh! Not sure if speccing up competitors to similar capacity actually gives a similar price to the Powerwall, I'll have to have a look around. Can one even get a Powerwall without solar?Is it usually worth getting more capacity than would be realistically needed? Meaning less cycles on the battery?
Soldato
The best thing about the powerwall is the electric tariff you get onto with it, last I checked it was import and export at 11.5p /kwh or something. The battery itself was hellishly expensive, but it made your unit costs cheap, and any generation worth more, so long term if the tariff keeps existing and being that competitive you'd save a lot no matter how much you used/generated.
Deleted member 651465
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Deleted member 651465
Can you clarify what you mean... who is offering that tariff?
Yes. You could just have it installed and charge it up with your existing tariff (good if you're on something like Octopus Go where the rate between 00:30 and 04:30 is 5p/kWh).
Yea I doubt we'd be able to afford it but we'll see
Is it usually worth getting more capacity than would be realistically needed? Meaning less cycles on the battery?
A powerwall is a 20-year investment, so you need to look at your future usage too. (i.e. A/C, EV cars). You can definitely use them without solar and charge them up overnight on cheap Eco7 rates.
Soldato
It's the Tesla Energy Plan - https://www.tesla.com/en_gb/support/tesla-energy-plan-faqs
Yea looking to go on GO once we've moved house as I already have an EV. Rate is now 7.5p/kWh though. But some quick man maths says at 25p difference (32.5p/kWh day rate) will save me about £625/year if we could get the entirety of our day usage onto a battery. This is partly the reason to look at a higher capacity storage system to make sure this is the case.
Hard to see it as a 20 year investment when the guarantee is only for 10 years. I know the Powerwall will continue to function after this of course, but capacity will be dropping...
Not sure we'd ever get A/C but of course have to think about maybe a heat pump appearing at some point. That said, we may plan to renew our boiler around 2029 and keep gas for a little while longer, depending on gas vs elec cost.
Soldato
Don't use GO with the powerwall, use the Tesla Energy Plan that I linked above, requires panels with the battery though.
Yea, we won't have the capital for any battery + PV system yet, let alone bumping the battery to a Powerwall, so that'll be a no-go at first. We're looking to split the installs - battery for load shifting/avoiding the day rate, then add solar a couple of years later to start generating.
Our front roof faces about 195 degrees so is almost south and the slight offset should cater for the house to the west of us being taller and giving unwanted shade as the sun sets.
Soldato
Anyone any idea when the Powerwall 3 will be released? Googling seems to suggest it's been on the horizon for at least a year.
Soldato
I'd wait and do panels and powerwall at the same time tbh if you're going down the powerwall route, with the VAT changes (don't know if it impacts battery costs) the panels are the smaller of the two expenses, and the savings you get will be far greater.
That and the new powerwall coming soon as a combo would probably be worth it if you're spending that kind of cash.
With a battery only set-up, the powerwall definitely won't cover all of it's costs in a 10 year timeframe. It's likely you'll be at the break-even point by that time, but certainly not "profitable" before that. My household use is average 10kWh per day and I am looking at an energy cost saving of ~ £1k / year for a battery system that covers that (assuming Eco7 rates and the predicted price rises in October).
Yea, there's so many variables it seems difficult to pin down exactly how much we'd save. Luckily my girlfriend is quite eco-conscious so we'd be going into this venture not just for attempted financial savings, it'd also be for green generation, helping the grid, running our peak load from battery etc... it's still a huge chunk of money though. I'm guessing we'd be pushing £15k for our install with a Powerwall.
The roof isn't the largest either. Looking on Google Earth suggests just over 6m x 4m, so I think we'd be lucky to to get anything above a 4kWp install of PV. The Octopus/Tesla calculator linked above suggests we'd be looking at about £262/year cost of electricity with 4kWp and Powerwall, which is an £800 saving on the ~£1,085 I've calculated we'd spend on Octopus GO without battery and having shifted some heavy load overnight.
Do you already have a smart meter fitted, and if so can you get daily / hourly figures from it?
The first thing you need to do is actually work out your daily / hourly usage for the last 12 months (at the very least, your energy bills should give you a monthly breakdown) then use those figures to see how much you'd be paying on an Eco7 rate + battery versus the current variable (and predicted rate rise in October) costs.
If you're excluding solar for now, the calculations are actually very simple because you know how many kWh you use already, and you're just looking at the Eco7 rate of 7.5p/kWh versus the ~47p/kWh predicted for October.
Soldato
We didn’t pay for the install. We purchased a house where the previous owner installed it. Looking at receipts the solar came in at £6k and £8k for the powerwall for the v2. I think that’s the total installation cost. It was a selling point for me as I anticipated energy prices increasing whilst we live here so it was a good gamble in our case. We paid over guide price for the house so I don’t think the previous owner lost much if anything on their investment.
Previously we weren’t on the Tesla energy plan. Current rate we are on with it is 11.76kwhp import and I think export is just a little bit higher.
Tbf, before we took the energy plan on I found it more beneficial to be on a normal tariff and use the powerwall at night/to morning for our energy usage. The bills seemed a little lower. I think the unit cost then was 22kwhp. Our impact usage was 70-90%.
Usually the powerwall in the winter months will charge using the grid then export back any electricity we haven’t used. Now the sun is out, it’s charging via solar and once fully charged it’ll send to the grid. The solar will also send to the house for the electricity we are using. Then the powerwall will send to the grid during peak hours usually between 4-7pm.
The Tesla app is putting our impact around 50% atm.
Having said, because we are south facing it is beneficial and the export helps offset the gas usage for us during the winter months so it isn’t too bad.
I will be getting another powerwall installed once the v3 is out and probably moving to an EV vehicle as they improve. If we move in the near future I’ll be investing in one again without second thought. It really helps save the pennies on a monthly basis.
Not really a good way to look at with the initial outlay you invest but if you’re living at a place for a long time then I think it’s worth it.
Hope this helps.