Home Batteries

I was wondering - has anyone has gone down the route of having batteries installed at home?

I had a 4kw solar system installed in 2020 and at the time, did the sums on batteries and decided they were not worth it. It seems a very new and immature market ripe for sharks to rip off the unwary and the pay back period didn't seem good value given that the battery is not likely to last as long as the panels. You need to be sure they have paid back before they are knackered and need replacing.

I worry that they are seriously overpriced, given that the battery in my car is 64kwh and, if they were to konk out completely and need replacing, is reckoned to cost around 10k. So why would a home battery cost around several thousand for only around 4-5kwh capacity?. I have been thinking that the best option is to wait until vehicle to home technology is commonplace and then I have a battery sat on the drive much of the time waiting to be exploited.

BUT BUT - the soaring cost of electricity has possibly changed the maths. If the difference between night rates and day rates stays above 20p per kwh that it seems to be now, that kind of halves the pay back period if getting batteries to fill up at night and use during the day.

Anyone got any thoughts. Have you done it. Was it worth it. Recommendations on what system - I was looking at GivEnergy which seem best value.

 

Got some triple As installed in my remote

 

Can I ask what kind of heating system you have at home? Combi or a traditional system, reason I ask is that we’ve just installed at solar I-boost to the hot water cylinder, basically when the controller defects that your exporting back to the grid it switches the immersion on and heat the water, I’m hoping that this will produce our hot water demands for a good 6 months of the year

 

It's a traditional system.

Sounds interesting. I have heard of similar systems, such as the Harvey? (Zappi)?

 

https://www.marlec.co.uk/product/solar-iboost/

Have a look at this, reviews are great, up-to 500kw of heat produced through the device, given how much gas and electric are due to go up to it’s imperative we can try to save as much as possible where we can

 

Thanks. Will take a look.

 

Is it possible to change to a economy 7 tariff then charge the battery up during the cheaper hours?

 

I have a huge lump of a battery behind a panel in a cupboard in my condo. I've never really worked out what it is meant to power. Every 3-4 years it starts to beep, and after I've changed the batteries in the 3 smoke detectors, I realize the error of my ways, and replace it. I believe someone said it was to provide power to a telephone landline in the case of an earthquake. I've no idea if that's even true, but I've not had a landline for most of the 16 years I've been here, anyway.

 

Renewable energy generators are waiting for electric vehicle ownership to be high enough to provide a national power storage facility. It's coming.

 

Is the idea to charge the car battery up during the night on economy 7 whilst it’s cheaper then use any power from the car battery during the day? If so a wonder if they’ll hike the price of Economy 7 up

 

Yes, I reckon it is.

 

That's the concept with home storage batteries. I have a dual rate tariff with Octopus called Octopus Go. But E7 is the same principle. 5p a kwh during the night for 4 hours and 14p per kwh during the day. But the current rates when my fix ends in August are 7.5p at night and something north of 30p in the day so making storage at night more appealing.

 

If you can size the batteries to your average daily usage in theory you would only ever pay the cheaper rate, or nothing if you can charge it with the PV.
I’d check the prices of batteries/inverters again now because they’ve dropped considerably in the last couple of years.

 

It has got be worth having a land line put in just in case we have an earthquake , if this does happen you could try to make a call , please let us know the outcome

 

The PV kit I just installed cost me around £3k, this was for a 4kw system, solar i-boost, scaffold and Labour too, I installed the panels myself so proud anti saves a fair bit there but if solar is used wisely it’s a great measure IMO

 

Check out EVM on Youtube.

He's been a long term EV car driver and has solar & home battery set up installed and done quite a few videos on the subject.

 

Yeah, seen those. Like a lot of the comments point out though, whilst interesting, his figures are too simplistic. They dont account for efficiency losses which would add 15% or so to his costs. Some of his average price he achieves is due to moving high load stuff to run overnight, which you can do without a battery. Also, the cost of the night rate has already gone up 50% since his video.

I think the pay back period looks a lot better since the price hikes but his numbers suggest it could possibly be 4 years. I think that's very optimistic.

The big issue I suppose is that bringing down the pay back time depends on the difference between day rates and night rates staying very high long term. I am not sure they will. I think the gap will close, either because day rates come back down in time to sensible levels or night rates go up as more EVs mean there is higher demand at night. Or both.

Think I am talking myself out of it. Need to do a good old spreadsheet.

 

We've got solar, a ground source heat pump, underfloor heating, no gas, and a 2.5kW battery. From May to August we're almost independent of the grid, depending of course on the weather. The solar/battery combination covers everything, including hot water. However, if we get an unseasonal cold spell and the heating comes on, or if we cook a big meal, we still need some additional power from the grid.

In September/October, and March/April the system can't cope fully as generally the heating will be on, but still makes a useful contribution. From November to February there's hardly any benefit because of the short days and generally poor light during the days. However, we're currently in Austria for February and the system is keeping things ticking over, as we're obviously not using anything and the heating is only on frost protection.

Our bills are (at current rates!!) about £1000 per year, all electricity, we don't have gas. With hindsight, we shoukd have installed a bigger battery, but we're happy with the system as it stands.

 

Can I ask a few questions please?

Can you describe your house? Age, size, type.
Did you have all those things installed or did any of them come with the house?
What was the total outlay?
Do you still need to put a jumper on in the house in Winter?

Thanks in advance.

 

You’ve asked all the things I was going to ask I’m dead keen to go as green as possible around the home