Can home batteries help save the climate and save you money?

[SteamyTea]

Can home batteries help save the climate and save you money?

Growing numbers of homeowners are installing batteries that store electricity when it is cheap, which helps balance the grid and cuts emissions, and cheaper plug-in batteries will soon let more people do the same

By Alec Luhn

25 June 2026

Home batteries can charge up when electricity is cheap and sell energy back to the grid at peak times

Mischa Keijser/Westend61/Getty Images

 

Think of climate solutions in homes and you will probably think of solar panels on the roof. But a suitcase-sized battery in the closet can be a cheaper way to save money and the environment.

Although rooftop solar has been expanding, battery storage is now the world’s fastest-growing power technology, according to the International Energy Agency, including home batteries that can power the house and sell leftover energy to the grid. Most of these are paired with rooftop solar, but as energy prices rise, more and more homeowners have been buying just the battery.

 

Now, countries are starting to allow home batteries that can simply be plugged in, rather than professionally installed.

“That could be the game changer… that I think suddenly opens it up to a lot more people,” says Iain Staffell at Imperial College London. “Low-cost plug-in batteries could be the next rooftop solar.”

More than 40,000 homes and small businesses installed battery systems in the UK last year with or without solar, nearly doubling the record from 2024. Installations of both home solar and battery systems by Octopus Energy doubled from February to March after the Iran war began disrupting energy supplies, and they have remained higher than pre-war levels as Britain’s energy regulator announced it would raise the state cap on energy prices.

 

In the US, home battery installations were up 75 per cent in 2025, even as rooftop solar growth slowed. The technology is also expanding rapidly in places like China and Australia, while in Germany, 1 in 6 homeowners have a home battery, making more than 2 million in total.

On a variable tariff, a battery can charge up in the early afternoon or at night, when electricity costs as little as 5 pence per kilowatt-hour in Britain. Then it can power the home when demand peaks from 4 to 7 pm, and a kilowatt-hour can cost 40 pence. Air conditioning and fan use during the current heatwave has driven that price up to nearly 50 pence.

While homeowners in the UK currently spend an average of £9400 on a battery system, Octopus’s forthcoming plug-in option will cost less than £300. The size of a shoebox, it will only store 2 kilowatt-hours, enough to run a fridge for one to two days, but it will allow renters to get in on the game once approved for consumer use, which is expected to be in 2027.

“You’re going to get return on investment in two to three years,” says Phil Steele at Octopus. “That should make it a no-brainer.”

Home batteries also cut greenhouse gas emissions by reducing consumption during peak times, so power companies don’t need to burn as much gas to supplement low-carbon sources of energy. On those windy, sunny, low-demand days when Britain’s grid briefly runs on almost 100 per cent zero-carbon sources, storing energy in a home battery can help the climate even more than generating unneeded energy with home solar.

 

Last year, the UK paid wind farms £379 million to shut down when the grid couldn’t handle that energy, a surplus that could have been partly stored in batteries. If half the homes in Britain had a 5-kilowatt-hour home battery, that would meet the government’s 2030 goal for battery storage, most of which is expected to be delivered by grid-scale batteries.

As the average share of solar and wind in the energy generation mix increases, home batteries will be even more crucial to balance the grid and even better for the climate, according to Staffell.

“Probably solar is better at the moment, but fast-forward five years, the batteries would be more important then,” he says.

However, the manufacturing process could lessen home batteries’ climate benefit, according to Aritra Ghosh at the University of Exeter, UK. There’s also currently no infrastructure to recycle millions of home batteries at the end of their lifespan, which Octopus expects to be at least 12 years.

A recent study found that producing a lithium-ion battery emitted about 150 to 200 kilograms of carbon dioxide equivalent per kilowatt-hour of capacity, about as much as driving a petrol car 1000 kilometres. This could be greatly decreased if hubs like China were able to decarbonise heavy industry, but “currently we are not even close to that scenario”,  says Ghosh.

[markc]

Good to see some groups are looking at the climate impact of manufacturing and end of life processing.

[SteamyTea]

26 minutes ago, markc said:

Good to see some groups are looking at the climate impact of manufacturing and end of life processing.

Most do, just does not get reported that often.

[marmic]

Can home batteries help save the climate and save you money?

 

Not sure to the first question - I'm not convinced.   And the second one I'd say eventually, but quicker for higher energy users! 

 

Decided against batteries due to cost and our energy use is very low anyway.  We produce more from PV than we can use during daylight hours so there was very much a possible argument for batteries - but would have taken a very long time to be financially beneficial.

 

And I'm not personally convinced that batteries are the answer anyway - albeit I've not researched deeply......... There are big environmental questions I have about batteries -  this is touched on in this 'report' but not properly answered.  I think the truth is hidden and/or not known -  nobody seems to be able to, or wants to, answer properly.

 

At what point overall do they actually become beneficial to the environment taking into account sustainability of production and mining etc? Not just CO2.

And ultimate disposal? I may well be wrong but as far as I know they aren't recyclable (??).  What will actually happen at the end of battery life?  I can only assume there will in time be a huge toxic battery land fill or similar? Maybe the moon........

 

My employer has EV only policy on company cars (which I need for my job unfortunately).  The last time vehicle changed I was given options, when reviewing these not one car company could (or would) answer these questions.  One did unbelievably suggest once batteries are worn out they will be used in houses!  But then even if feasible what happens once properly worn out?  My understanding is production of EV vehicles is more environmentally damaging - there must surely be an average mileage of a vehicle when it begins to pay off and become beneficial.  But this will be variable of course dependent on production - and probably not possible to answer accurately anyway as also subject to how clean the energy is used to charge! The same principle applies to home batteries too - or for that matter any batteries! 

 

and as for government grant for EVs (if still running?) this has to be mainly just giving money to those who can afford an EV and would buy one without the grant anyway! Yes there will be exceptions I am sure.  But this is a whole different topic!

 

Would be interesting if anyone can throw some more light on the subject.  The truth is out there - or is it?

 

Now to be non PC -  there are too many humans on this planet!  The sun is the source of all our power (well most of it), and we are the source of most of the problems  

 

[markc]

@marmic .., too many humans …. Couldn’t agree more, now let’s see which groups really care about the planet and volunteer cut the numbers.

[saveasteading]

A couple of comments.

Thd article says a £300 battery is sufficient to run a fridge for 2 days, and pays itself in 3 years.

But this month's which magazine says a fridge freezer costs £30p/a to power.

Does not compute.

2 fridges cost £60p/a. 5 years. So a decent return but not ground breaking due to the small scale.

Add financing the £300 and it's not great. This also assumes that it's all automatic.

 

Recycling. I understood that I take batteries for recycling rather than for safe disposal.

 

[JohnMo]

Just looked back at our gas and electricity bills in 2023, we had £89 Direct Debit for gas and £180 for electric. Since then I have added more solar and a battery. Plus we now get export payments. Plus got rid of boiler and installed an ASHP.

 

Battery and additional solar cost me around £7500. Fully installed.

 

But current DD is a total of £52. Instead of paying normal rates for electricity I pay 10p per kWh, can only do this because I have a battery.

 

So in simple terms I am saving £214 monthly, or £2568 per year. Nice round 3 years pay back on the additional solar and battery.

 

And an added bonus, this month via Axle VPP, have earned an additional £20 directly from having a battery. So taking this into account in the the above, now pay back becomes 2.7 years.

[Russdl]

Our DD has just been reduced from £29.17/month to £8.00/month. A more accurate figure for our import over export would be £0.00/month

 

We are only in this position because of solar PV, battery storage and an EV. The EV gives us access to cheap overnight rates that we utilise to run everything when required plus charging the house and car battery. 
 

I don’t obsess about RoI and I don’t ask anything else to return the investment (car, kitchen, hi-fi stuff etc etc etc) but on the current trajectory the solar and battery should be paid for in a total of 8 years. 

 

[saveasteading]

18 minutes ago, JohnMo said:

now pay back becomes 2.7 years.

That's good and also a tidy sum due to scale.

But would you bother for £60 a year? To which apply that it takes space, needs funding which not all can afford, and of course the risk of failure.

 

But perhaps if all new homes had one fitted as standard that would be 1. Cheaper, 2. A big deal on the national scale.