Solar fed house battery - has anyone installed one?

  • 21 March 2019
  • 7 replies

Solar fed House battery, has anyone installed one?

I've read about 2nd hand electric car batteries being installed in a house (Tesla and Nissan) and then used to store day time solar energy for use at night to power the essentials in the house.

Anyone tried this and how horrendous is the price?

7 replies

Userlevel 1

Hi Guys


Meant to also say that the tou tariff I am on with Octopus, Octopus Agile, occasionally goes negative prices, this means that sometimes (2 nights this year) they actually pay me to take electricity from the grid. There has also been some times when electricity prices have been only 1p - 2p per Kwh and many times its been 4p - 5p per Kwh overnight.

Hope this all helps

Many regards Pete

Userlevel 1

Hi guys

I am not with OvO for my electricity and gas anymore I went to Octopus due to them having a proper time of use tariff.

To answer your questions during the Autumn and winter I set the batteries to charge up during the night on cheaper tou electricity, then during the day the tariff I am on because its for battery owners its cheaper up until 16.00 then gets very expensive until around 20.00, so my battery does not take the load until 16.00. It then usually lasts until I re-charge around 02.30 or so. So this way I am being rewarded by Octopus with cheaper electricity for not taking electricity during the peak times of 16.00 - 20.00, early days yet as only changed to them in September but do expect to see some savings from this usage.

I went for the el cheapo Chinese Pylontech batteries and a Sofar Solar inverter both of which so far have been very reliable.

I know they will probably only last around 10 years, 15 if I am lucky but I am relying on the FITs payments to pay for them so not to worried about getting my money back on them over their lifetime.

So Autumn and winter savings not so good but summer they are excellent as I get solar PV from early morning to around 15.00 which also charges the batteries, then the batteries take the load until around 02.00. So Summer time almost free electricity.


Regards Pete.

Also, don’t want to pry, but what battery brand did you opt for?

@Llamedospete - thanks for sharing. Have you been able to fill your batteries this autumn? We’ve had a lot of dreary, gloomy weather and solar production has been poor. We never opted for batteries and wanted to hear about your experience.

I’m about to have a solar power system installed at my home. The friends and relatives I’ve told divide into two groups, those that are all for it and want to install at their homes too and those who come up with the usual objections of lack of Government grants, ending of feed-in tariffs and cost and longevity of batteries. As for batteries, there are limitations and costs but the way I see it is that battery technology is always advancing so performance and affordability will improve. Apart from the environmental benefits of solar power, I calculated how much the cost of installation was earning sat in the bank and how much it could save on electricity on a daily basis and it was a no-brainer. I moved over to OVO because of its environmental ethos and forward thinking. I must say I’m a little disappointed that OVO hasn’t taken a lead in promoting domestic solar power production through offering competitive substitutes for ‘feed-in tariffs’.

Userlevel 3
Very interesting response @Llamedospete,

Although we currently don't have a model of solar fed home batteries in the pipeline yet, we've been working hard on getting our first Home Energy Storage batteries trialed. You can find more out about this here!

We're currently in collaboration with Nissan in order to bring the home battery storage to fruition and hopefully make this available to our customers in the future! Solar fed batteries could also be a possibility in the future too!

Here's a link for more information on that here.

Userlevel 1
HI. @chrisjw37
I have installed home batteries back in January to compliment my 4kwp of solar PV.
I found that price wise anyone who works in the solar business were charging you double the price of the batteries to supply and install them.
So if I wanted say 7kw of batteries at a cost of £3000.00 they would charge you £6000.00!
I was not interested in keeping the local PV installers in new BMW's and found that wholesalers are selling complete kits online.
I went ahead and ordered a complete kit of 7.2kwh of batteries and a 3kw inverter for £3500.00, I then had to find an installer and I really hit problems here. None of the local solar installers were interested for the above reasons of pure greed as explained above, after some research I found that to install batteries unlike PV the installer does not need to be solar accredited as batteries are not regarded as a generator if the inverter is A.C. connected and does not provide any power out to the grid. So one electrician later I had the batteries installed for £60.00! And another £20.00 for his friend to register them with the local electricity supplier they were up and running.
So far very pleased with them, making a big difference to my electricity use and costs.
If you want to know anymore let me know.
Rregards to all Pete.