Solar battery storage.

[john999boy]

I'm currently considering adding some battery storage to allow my daytime generation to supply the house during the evening and potentially during any loss of grid power.

It seems that the Tesla Powerwall 2 would be a good solution (even though they're virtually unable to be sourced) but that may also be because a Powerwall 3 is incoming?

 

There is definitely a price premium to go to Tesla (which would probably be the optimal storage/discharge) but wondered if others had any other solutions even if I missed out on the loss of grid power option?

At the moment there's no EV in the equation.

[cheezemonkhai]

Forget the Powerwall the lead time in UK is at least 12 months and we had an order delayed and delayed and delayed over it.

 

Anyone the suggested they have stock or short lead times is highly likely to be telling porkies.

 

Most hybrid inverter systems can do some backup and solar recharge with suitable earth/isolation etc.

 

Most can do backup eps but won’t recharge, again subject to wiring etc. I believe GivEnergy are also coming out with a gateway and 13.5kWh usable all in one battery fairly soon.

Edited 5 November, 2022 by cheezemonkhai

[john999boy]

I appreciate there’s a long wait for the Powerwall but I’m not sure GivEnergy is an option.

The 13.5kWh option is adequate but that may involve an additional inverter and still can’t do grid backup (AFAIK).

 

[cheezemonkhai]

The 13.5 includes the inverter and a gateway which can deal with multiple inverters.

 

If GE isn’t ok look at SMA sunny island👍
 

FWIW we ordered a Powerwall a year ago and there was no sign. There’s rumours they are being kept for full solar/battery installations only, which we were but frankly it’s all a case of who knows.

 

You’d still need a g99 and if you join the Tesla tariff you’ll lose your FIT.

Edited 5 November, 2022 by cheezemonkhai

[SteveTheElder]

I've been looking in to adding a battery too. The guys who installed out solar panels 7 years ago reckon they could get a Tesla Powerwall 2 in Q2 next year so maybe timing depends on the installer &/or their market history /reputation.

 

Alternatives I've considered are SoalrEdge (existing inverter is that brand) but by the time I add on an update to the inverter and the module for power protection (for power cuts) they're about the same price as the Tesla.

 

I've done some analysis of our consumption (import), export, and self-consumption to work out the potential payback time. It works out to be 10+ years which I reckon is a non-starter given the battery will be pretty much useless by then. A shame really 'cos getting a battery does feel like the right thing to do. Heyho!

 

@john999boy do you have a hot water cylinder? If so, have a think about a Solar iBoost (or similar) which send surplus generated power to the immersion heater. That's how we heated ALL of our hot water from April to end October this year.

[cheezemonkhai]

I ordered a PW2 late 2021 and if we’d stayed it wasn’t turning up until q2 23 earliest.

[cheezemonkhai]

The IBoost/immersun/Eddie is a cheap way to save on gas… depends if you want backup power or more bill savings👍

[john999boy]

8 hours ago, cheezemonkhai said:

You’d still need a g99 and if you join the Tesla tariff you’ll lose your FIT.

I definitely don’t want to lose my premium FIT but why is a (chargeable) G99 required when I’m not actually increasing capacity - just usability?

 

5 hours ago, sneal said:

do you have a hot water cylinder? If so, have a think about a Solar iBoost (or similar) which send surplus generated power to the immersion heater. That's how we heated ALL of our hot water from April to end October this year

[john999boy]

I’m currently using an Immersun which does the same thing - a marvellous piece of kit!

Edited 6 November, 2022 by john999boy
Typo

[cheezemonkhai]

7 hours ago, john999boy said:

I definitely don’t want to lose my premium FIT but why is a (chargeable) G99 required when I’m not actually increasing capacity - just usability?

 

The g99 is required because the Tesla can do a 5kW output and so you need the g99 approval. I went through this.

 

If you can find an AC coupled battery that is below 16A, you might be ok, but probably not because your solar can potentially export at the same time. The only way to be certain is to check with the DNO.

[Aspman]

We'd like to look into solar/wind battery but the market seems to basically be a cesspit of chancers with a few decent companies in the mix