Which battery set up to go for?

My 3-bedroom detached house is all-electric.
My objective is to install battery storage that makes it possible to buy electricity at off peak rates then supply the whole house in the cold months during peak times (6-8am and 4-8pm).
I want to install GivEnergy battery storage, but I'm not sure which setup to go for.
Heating in the house is via eight rads which total 12kw, (but are never on all at once).
Have 8kw solar.
Currently on Octopus Agile.
Any advice and suggestions are greatly appreciated.
Thanks.

You need to look at how much you use and at what time of day. The Loop Energy app is good for that, and then you can work out the battery capacity needed. I am guessing it will need to be big one for electric radiators.

JohnF Look at you bills, this will give you typical usage per day - obviously winter being the heaviest use.

The other import factor is the rate at which you use the power. The All In One can charge/discharge at 6kW other inverters are much lower.

So, when you are heating the home and have the cooker/immersion heater on check to see how much power is being consumed. There is no point in having a large battery if it cannot deliver the power you need.

Its a little easier for me as I don't have solar but use the AIO for the same thing - you really don't want a lot of spare capacity in the battery is the main thing unless you know your future plans would need that extra (like for us planning to ditch the gas/electric cooker for electric).

My advise would be look at your usage by quarter, with summer being the high solar lower battery need and winter the opposite, and then strike a balance between them which should be closer to the other quarters. Spreadsheet the savings by quarter and work out the payback based on covering worse case and middle case till you get to a position where your payback is best or at least acceptable.

Idea is if your say using 1kwh of the battery a day and it costs you £600 for that battery capacity (cost of install/13) if you use it each day your paying off that £600 a lot quicker say 22p per day around 7.5 years if you only used that 1kwh for 6 months of the year your payback is 15 years, if its that long you have to factor in will you still be at the property then and will being out of warranty be much of a risk....

Of course in all of this the risk is the price you pay for the electric so there is an element of a gamble here.

DreadorUK great advice about sizing the battery to meet your usage and not over size it. I see YouTube videos with people whose battery runs at 60-70%. That means they’ve paid for capacity they are not using. Batteries have come down in price but they are still relatively expensive with poorer payback than solar panels that are largely maintenance free and last 20+ years.

JohnF take a look at the Gary does solar videos on YouTube

JohnF As you're on Agile then first thing is to look at the Agile bills/data to work out when you import the most power and what that peak power is.

Electric rads complicate matters so best to look at Agile billing data to see what/when you're actually using.

You may well find its simply not worth putting a battery in as its unable to supply the full home load when you want it. By that I mean your normal heating usage in cold months will still potentially be importing power from the grid as the battery/inverter will be unable to supply the power required. I suspect that isn't something you've thought about yet?

Agile makes it nice & simple as you can download your energy usage stats in 30 minute intervals.

JohnF Have a good read through all the problems reported with the AIO on these forums, esp one "Steer clear of AIO?"