Getting a second battery

Spoke to my installers about having them install a 2nd battery... how it would cost if I bought the battery direct vs how much for them to supply and install.

The difference was roughly £60.

So I'm waiting for them to get back to me a time frame for installing the 2nd 5.2kwh battery... they said it would be about £2800 back in Feb when I enquired... it's actually going to be £2400 inc VAT

I can cover that with what I've saved this year on bills (currently £780) and the £150 I put away for house maintenance and repairs each month.

Don't even need to touch my savings and house DIY funds.

Good work! My second battery was - with 20/20 hindsight - a really good idea, especially with access to tariffs like IO. I hope and expect the upgrade all goes well for you.

Anomnomnomaly if you can stretch to it, buy an 8.2 or a 9.5 battery.

The 8.2 is about £1000 more but it’s 100% depth of discharge rather than the 80% on the 5.2.
So you’re getting twice the battery capacity for less than half the extra cost

geoffreycoan

It's £2400 for the 5.2, it's £4100 for the 8.2... I don't have the extra and with an avg use of 16-17kwh a day, 10.4kwh with a usable 9kwh (mine currently gives in the 4.6kwh range) that will easily power the house

the 5.2 powers the house for 4-5hrs including a little bit of cooking, right now it lasts until after 9pm, sometimes as long as 10:30pm.

The cost/math/generation figures don;t make sense for a larger one... What I should have done was have the 9.5kwh installed to begin with... But I had a strict budget back then and couldn't afford it. We'd just found out that the 6k we'd allocated for some repairs on the house we bought... we're actually going to cost 14k. So finding an extra £2000 for the solar/battery installation just wasn't possible.

Now, spending the extra £1700 simply doesn't make sense... I'd have to put of getting it done for 5-6 months to save up the extra... and risk the prices rising even further.

I make these calls based on hard facts about the way we use energy and the current system... it's the right choice for us.

I had a second battery installed a few weeks ago. Now have to have two GE accounts as apparently the software cannot cope with more than one battery 🙁

ISains
Do you have 1 inverter with 2 batteries installed? Are they the same size batteries? I was quoted if having multiple batteries needing to be the same battery 5.2 with 5.2, 9.5 with 9.5kwh etc.

Anomnomnomaly Fair enough, you've got the prices and have weighed up the different options based on your needs.

I bought a 5.2 with my original installation as the installers wanted silly money for the batteries and so I bought the cheapest I could. I then added a 9.5 that I bought direct from ITS technologies for £4000 that my installer then fitted.
TBH I would rather have had at least two 9.5's. The current 14kW meets summer and autumn usage of about 16kW a day, but in winter the heat pump pulls a further _20kW. For me adding a further 3rd battery the cost/benefit doesn't pay back at all regardless of what size I go for.

Batteries have dropped in price over the last year so hopefully they will continue to get cheaper as they certainly free you from paying high import charges.

ISains did you have your battery installed by the same company as your original installation? You can certainly have multiple batteries on the same account, I have two inverters on my one account, one battery on each.
I have heard some installers think you can't have this though and customers have ended up with multiple accounts as a result.
If you contact Givenergy they may be able to merge the accounts for you

geoffreycoan
2 batteries two inverters all supplied and installed by the same company.

ISains OK well they have set it up wrongly then. I had my second battery installed by the same company as my first. Maybe the engineer didn't know how to add a battery to an existing configuration and only knew the 'brand new customer setup an account' process?

But definitely two inverters one account is possible. I have it

Just on phone to GE. They say not recommended to have two on one account

ISains Why not?

geoffreycoan

I just had an email from my installer about the 8.2kw battery.

He said he'd quoted the old price before, and it's now £2750+VAT =£3300, which is only an extra £900... and I can afford that.

I've also spoken with people about switching to octopus agile as that gives very cheap rates overnight... Can time shift, washing machine and dishwasher and charge battery up between midnight and 4-5am, save some in reserve for peak hours. I think it also allows 15p export rate.

So I might do it that way... appreciate the suggestion... £1700 was too much for a decent ROI, but £900 makes it more workable.

Anomnomnomaly excellent news, definitely worth doing, double the battery capacity and yes opens up more options for time shifting your consumption.

And you can get 15p export with agile. At the moment overnight you can charge at 6p with agile so potentially make a profit like this! I’d rather keep the cheap electricity for when it’s not sunny

geoffreycoan

Yeah, coming around to the idea of time shifting everything... putting 75% into the batteries during the night over winter, let that run the house until solar can take over and maybe if required, recharge the battery enough to cover that important 4-7 peak rate time if solar isn't strong enough to do it.

I can delay the dishwasher and washing machine star times for up to 9hrs.

I'm more concerned about using as much of generation as possible because we exported almost 1100kwh and didn't get paid for it... and at 3p which is what we would have got before... was worth about £31.

But if I reduce import further, the savings are huge now we're no longer protected by a cheap fixed deal, as that ran out end of Sept. Gotta prepare for more energy crisis hikes.