On-grid domestic battery storage

Coastalwatch

Hi Alshamal, those prices seem to be about the going rate in todays climate, so not sure if you could better them elsewhere.

You don't say whether it's in combination with a PV array? Afraid I cannot say whether either will make a ROI but our's are serving us very well presently, with no regrets to their purchase.

Alshamal

Hi no PV 🙏 just need some confidence to press the button!

Alshamal

Just been reading on the Facebook page someone said life expectancy 12 years 6k spent need to get £500 back a year to break even!

Exiled_Tyke

Alshamal said:

Just been reading on the Facebook page someone said life expectancy 12 years 6k spent need to get £500 back a year to break even!

If my memory is correct the standard rate of electricity is going up to 40p?  So the saving over your 7.5p rate is 32.5p.  Multiply this by 365 days and say a 9.6kWh batter of which only 90% is usable.  That comes out at £1024 per year.  As long as use that amount of electricity it looks like a good investment. However the question is what the price of standard and cheap rate electricity will be in the future.    (I would add given my comments elsewhere that this is not the best way to assess such an investment but the 'rough hand' calculation is probably good enough) 

chamelion

Alshamal said:

Just been reading on the Facebook page someone said life expectancy 12 years 6k spent need to get £500 back a year to break even!

my US3000C (approx 3.2kwh usable) was bought for £860. 
Some man math:
Charge at 7.5p/kwh and let's say lose 10% in inefficiency = 26.4p for a full charge. 
Discharge saves me spending 39.34p peak times = £1.26 saved. 

Saving on this one battery for one cycle per day = roughly £1. 

ROI = under 2.5 years using above math. 

Of course other factors in play - for e.g. maybe peak electricity will go cheaper or offpeak electricity will go more expensive. But, conversely, i'm not accounting for my solar which is charging my batteries for free, so I could even be avoiding the 26.4p per kwh for charging. 

of course there are other costs for inverter + electrician etc - i'm just looking at battery above. but i got everything else at stupidly cheap prices in 2020 with a battery upgrade in 2021 when prices were starting to climb up. I think there's still a possibility that at today's ridiculously inflated prices that it's still worthwhile - although i'm guessing significantly longer than the above.

Coastalwatch

Alshamal said:

Hi no PV 🙏 just need some confidence to press the button!

Afraid none of us have a crystal ball and while there may be a financial justification for a battery under current rates the future is unknown, so whatever calculations are used the purchase will be something of a wager which may or may not make a positive financial return. I've no idea of the warranty period of your chosen battery but our's is for ten years, so taking one complete cycle each day then by simply dividing the total cost by the number of kWh's cycled ours works out at 12p/kWh. I've no idea if they will ever make a postive return financially, but we're making good use of them and keeping bills manageable as a result. I see it as something of a challenge to become as energy independent as we can, with battery storage playing an important and not insignificant part of it.

Whilst I relish the challenge we face, I appreciate others may not have the time or necessary interest to do similar.

With smart metering and half hour billing now prevalent then Time of Use tariffs can play a role in grid balancing with the necessary financial incentives to encourage us to take part. Having battery storage allows access to this.

If you've funds available then the cost/kWh is less with the larger battery and with us being encouraged to transition away from fossil fuels, as you appear to be doing, I do not believe this would be too large for your needs.

Alshamal

Still waiting for the confirmation of Go rates! It’s looking like 34p fixed for 2 years is favourite ! So that’s look’s like another reason not to press the green button!

chamelion

Alshamal said:

Still waiting for the confirmation of Go rates! It’s looking like 34p fixed for 2 years is favourite ! So that’s look’s like another reason not to press the green button!

How does that work? The new 2 year cap is higher than current cap, and current cap is well over 34p? 

QrizB

chamelion said:

Alshamal said:

Still waiting for the confirmation of Go rates! It’s looking like 34p fixed for 2 years is favourite ! So that’s look’s like another reason not to press the green button!

How does that work? The new 2 year cap is higher than current cap, and current cap is well over 34p? 

Current cap is about 28p. New cap was going to be 52p but is expected to be reduced to 34p.

EVandPV

Our current Go tariff ends on 14th September.
I'll report back once we get word of the new rates, should hear in the next few days.