• Base Power raises funds to roll out a new Base Core model
• It protects against power outages and gives back to the grid
• The battery is available to purchase in Texas and Illinois initially

What with plug-in home solar becoming more widely available and household battery power storage increasingly common, there's growing momentum behind home energy solutions that help to lower electricity bills and reduce pressure on the grid.

There's more evidence with the news that Base Power just raised a cool $1 billion to scale its large Base Core home battery (via Interesting Engineering): the battery is available in 39.2 kWh and 78.4 kWh versions, and while it's capable of keeping your home running during power outages, it does a lot more besides too.

Base Power says the Core can be installed in under an hour, can be switched to seamlessly, and will handle extreme weather events too (it works in temperatures of -22 to 122°F or -30 to 50°C). If the standard power network goes out, the Base Core can keep your home running for 36-72 hours depending on capacity and configuration.

When the power's not out, the Base Core can still reduce your reliance on the grid and cut down on electricity bills. It's also designed to support the grid, feeding back electricity when additional capacity is needed (though there will always be some in reserve for you). That helps to keep up-front costs down.

Texas and beyond

The Base Core is now available in Texas and Illinois, with pricing dependent on your utility provider. A typical cost listed on the Base Power website is energy for 13.1¢ cents per kWh, a membership fee of $19 per month, and a $695 up-front cost for the battery.

As more of these batteries are installed, the better the system will work, in theory. Base Power says it's installed battery capacity has grown to more than 500 MWh over the past year, while more partnerships are being signed with electricity companies. After this latest funding round, the company is valued at $13 billion.

There certainly seems to be the demand for these money-saving, energy-storing batteries: last month Ars Technica reported that US home battery installations had hit a new high for the first quarter of 2026, with new units accounting for 673 megawatts of energy supply. For the same quarter, around 1,300 MWh was installed in terms of capacity.

Google has also invested in the idea of tapping into distributed household energy systems, via a deal with Voltus, in part to manage the growing demands of its AI data centers. For home users, the benefits are clear: protection against both rising electricity prices and an increasing number of power outages in vulnerable areas.

With plug-in batteries also on the road to legalization in some countries, it does feel like a home energy boom is coming – and that could help us all navigate the energy crisis and our soaring bills.

• Solar energy just had its best-ever month in the UK
• Rooftop panels and farms provided 14.4% of the country's electricity
• The record comes ahead of the legalisation of plug-in solar kits soon

Our gardens may be wilting in this exceptionally dry, sunny summer in the UK, but one thing that is benefitting from all the rays is solar panels. Solar energy just had its best-ever month for supplying power to the grid — and plug-in solar panels are aiming to keep that run going when they become legal later this month.

Alongside solar farms, rooftop panels — which are surging in popularity — helped provide an impressive 14.4% of the UK's electricity in July (via The Guardian). That's 50% more than this time last year, according to National Energy System Operator (Neso) data, and helped to power the fans and air con units we're all relying on to survive while working from home.

The record comes from a combination of two factors. The incredible amount of sunshine we saw in July helped — the UK bathed in around twice the amount of sunshine hours that it usually gets on average at this time of year.

But it was also powered by the popularity of solar panels, which many are installing to help cut their energy bills in the UK. The country saw more solar power installations in the first half of 2026 than in any similar period for 15 years, while last year saw the highest total number of solar installations (269,000) ever recorded in a calendar year, according to government data.

Those figures include ground-based solar farms, but a significant proportion (just under a third of the UK's total solar power) is provided by rooftop panels. However, with these panels still prohibitively expensive for many, eyes will now be turning to the legalisation of plug-in solar kits from August 27.

Can plug-in solar add some extra shine?

It's unfortunate that plug-in solar panels weren't legalised a few months ago, when they could have contributed to these record UK solar energy figures.

Still, the UK government made the welcome announcement last week that these plug-in solar kits — which can send electricity into your wall socket without needing professional installation — will become legal from August 27. That's good news if you've felt frozen out of solar due to its cost, a lack of roof access or the fact that you're renting.

The Statutory Instrument 2026/848 clears the blocks that previously prevented UK residents from buying self-installed, ‘plug-in’ solar systems. The August 27 date is more of a legal landmark, so it isn't clear exactly when these kits will go on sale. But you can expect to see them in the likes of Lidl, Currys and Amazon soon, when they'll apparently cost around £400 and could save households up to £70-£110 a year.

While many have argued that plug-in batteries could be the real home energy revolution (they were left out of the government's new legislation), the combination of this new solar energy record and the legalisation of plug-in solar kits later this month means that renewable energy is having a big moment.

"Fifteen years ago, solar energy was a footnote in the electricity mix," said Chris Hewett (Chief executive of Solar Energy UK). "Now it is a major player, delivering homegrown, cheap, clean and reliable energy."

“The UK is firmly in its second solar boom, joining the trend we’re seeing worldwide, as households and governments look to it as a low-cost and local alternative to oil and gas,” added Frankie Mayo, a senior analyst at Ember.

The UK is still well behind Germany when it comes to balcony solar (which is called 'Balkonkraftwerk'), as you can see in the graph above, but at least the country's sun-powered potential is now finally on the charge.

It's typical, you wait for ages for a home energy revolution and then two come along at once — or at least that's what appears to be happening in the UK.

You've probably heard about the first landmark moment. 'Plug-in solar' hit the headlines last week when the UK government announced that small, solar panel kits that feed electricity directly into your standard home socket can legally go on sale from August 27.

That's a big deal. Plug-in solar means that millions of people who have traditionally been locked out of generating their own clean electricity — renters and flat owners, for example — will be able to join the residential solar party, albeit on a more modest scale.

But not everyone was celebrating wildly with biodegradable confetti. Across the country, energy nerds bemoaned one glaring omission in the government's new legislation — a legal pathway for 'plug-in batteries'.

For many, these small home batteries — think a mini Tesla Powerwall that plugs into a standard wall socket — are the "real game-changer", as Octopus Energy and Anker both described them to me. That's because they promise to be even more accessible than plug-in solar and act as a money-saving brain that makes your home an active part of a smarter UK electricity grid.

Bold claims indeed, so I spoke to four of the biggest players in this burgeoning space — Anker, Octopus Energy, EcoFlow and Windfall Energy — along with the UK government to find out when plug-in batteries might be coming, what the drawbacks are and, most importantly, how much you can really expect to save...

When are they coming?

The main premise of plug-in home batteries, like the Windfall Battery above, is simple — they charge automatically using cheap-rate electricity (usually at night), then discharge that electricity around your home during more expensive peak-rate periods. "Even without solar panels, a plug-in battery delivers meaningful savings through grid arbitrage alone," Anker Solix's EU CEO, Kelvin Cao, tells me. Savings estimates range from between £100-£400 per year, depending on your battery, tariff and usage.

Great, so when exactly will they become legal in the UK? When I asked the Department for Energy Security and Net Zero (DESNZ), the official answer was predictably vague. "We are rolling out plug-in solar, which will be quickest to reach the market — helping to bring bills down for good," a DESNZ spokesperson said.

The DESNZ told me its main focus right now is plug-in solar kits and that plug-in batteries have their own technical and regulatory hurdles, which it's currently investigating. Still, there are hopes that grid-connected batteries that plug into your wall socket could be legalised within the next year.

Several big players are quietly preparing plug-in batteries — which are already available in countries like Germany — for a UK launch. Anker, for example, has built a page for its Solix Solarbank 4 that clearly explains the benefits of plug-in batteries, should they become legalised in the UK. "We are eager to support the rise of the plug-in era in the UK and become part of its evolving energy landscape," Anker Solix's EU CEO, Kelvin Cao, told me.

Octopus Energy also recently announced that its new plug-in Nook Cube battery will go on sale sometime in 2027. More confident on the timescale is Windfall Energy, a London startup that's designed the best-looking piece of home energy kit I've seen for a while, the Windfall Battery.

"I was at a roundtable with a Minister of Parliament about a month ago, and everyone there was pretty much calling for batteries to come hot on the heels of plug-in solar," Windfall Energy's co-founder Rob Hallifax told me.

So when is Windfall expecting to start selling its 2.5 kWh home battery, which has an RRP of £1,200 and had previously been slated to ship in autumn? "Winter is more likely now. We want to time it with the plug-in regulations. It’s looking like the end of this year, early next," he added.

Why now?

You'll probably have noticed that the UK has been on an energy rollercoaster that can technically be described as 'not fun'.

Back in the late 1990s and early 2000s, inflation-adjusted gas and electricity prices were actually stable or even falling. But there was a huge spike for both in early 2022 and they've never returned to pre-energy crisis levels. Electricity prices are still 13% higher than in January 2020, according to the UK government, and they continue to move in the wrong direction.

Plug-in batteries promise to be, if not a cure, then at least a much-needed pain killer for our energy bills headache. They're emerging now because of three things — falling prices for lithium-iron-phosphate (LFP) batteries, the easing of electrical regulations in some regions (Germany created the world's first dedicated plug-in solar product standard in late 2025), and soaring wholesale gas prices that are reflected in the graph above.

As Anker's Kelvin Cao tells me, this has "reshaped how European households think about electricity". Unfortunately, that double-digit increase in energy prices is also "unlikely to come down any time soon". That's why Germany started the trend, and the UK is (hopefully) about to follow.

So how exactly do plug-in batteries save you money? "There’s two parts to the price saving," Windfall Energy's co-founder Rob Hallifax tells me. "The simple one is just the price arbitrage. So if you're paying 10p at night and 30p in the day for electricity per kilowatt hour, then you buy it at 10p, use it when it's 30p, you're saving 20p per kilowatt hour," he says.

That part's pretty simple — with the Windfall Battery, this 'buy low, use when prices skyrocket' approach makes up about £168 of its promised £250 per year savings. But there are also extra savings from getting your plug-in battery really singing in tune with the electricity network.

The UK grid acts a bit like a giant smart thermostat, signaling when the system needs more or less electricity, and the idea is that energy suppliers could follow by telling plug-in home batteries when to charge and discharge. Smaller plug-in batteries would likely be capped at an 800W output (without professional installation), so wouldn't be exporting power to the grid. But they could still play a role in balancing demand.

This makes tariffs the second big factor in the money-saving potential of plug-in batteries — and that's something Octopus Energy has been a UK leader in.

"The energy sector overall has not really embraced the fact that you can just offer different types of products to different types of consumer customer groups," Alex Schoch, Group Director for Flexibility at Octopus Energy, tells me. "Of our eight million customers, 1.2 million are on some kind of smart tariff," he adds.

Octopus Energy told me there could potentially be dedicated plug-in battery tariffs or bolt-ons for existing ones. If you've ever been baffled by choosing the right energy tariff, this could also get simpler thanks to plug-in batteries.

"I equate it to the evolution of mobile phone plans," Octopus Energy's Alex Schoch tells me. "First, they were incredibly generic. Then they got so complicated that Carphone Warehouse came into being just to explain the complexity. And now we’re at a stage where we create hyper-personalised plans based on your needs as a consumer. We’re on that same journey when it comes to energy".

But doesn't this also demand a lot of trust in energy companies? Windfall Energy's Rob Hallifax agrees, but thinks falling bills will ultimately convince consumers. "It's their (consumers'] battery, they're in control of it, but the energy company is controlling it a bit to help them maximize the savings," he says. "The consumer has to trust that the energy company is doing this to save them money, and I think that will come when they see their bills go down," he adds.

What's the catch?

Clearly, plug-in batteries won't be a magic wand for everyone's bills, even if the batteries could be subsidised or even given away for free by the UK government to lower-income households, as the i Paper reported recently (the DESNZ declined to comment on this when I asked).

For most plug-in batteries, the payback period (the time it takes for savings to cover the cost of the battery) is expected to be around 3-4 for years, so not exactly a financial quick fix. The Windfall Battery promises annual savings of £250 (with an RRP of £1,200), while Anker tells me that the larger Solix Solarbank 4 on a dynamic tariff like Octopus Agile could save you just under £400 per year. That battery has no UK price yet, but retails for €1,999 in Europe (around £1,700).

The other concern raised by skeptics is safety. Is allowing potentially millions of households to connect batteries to their electricity networks without professional installation really a good idea? Windfall Energy's Rob Hallifax acknowledges that it's an understandable concern. "People see a battery, and they think of scooters and fires, and there some valid concerns. Obviously, safety is critically important, and just one battery fire would be one too many," he says.

"But modern batteries are generally extremely safe,' he adds. "There are some studies out of Germany now where they compare batteries to EVs and other home appliances. One headline is that they’re typically about as safe as a washing machine," he adds. The other common comparison is with fan heaters, which are legal in the UK but carry a higher risk of 'user error' incidents than plug-in batteries.

Still, the added complexities of grid-charging batteries mean some agree with the UK government's top-dipping approach. EcoFlow, one of the biggest global players in home batteries, is among them. "We're aware and completely understand that these things take time," Lorna Wallace-Smith (EcoFlow's Head of UK PR) told me. "The fact that they were able to move forward with at least one step is is great" she added.

But hasn't Germany's rapid adoption of both plug-in solar and home batteries shown it's safe? "I think that's something we should learn from, as well as not fast-track into something without knowing it's absolutely built for UK homes," she added.

Could they outshine solar?

Despite these concerns, it seems clear that plug-in batteries have the potential to eclipse the more complex plug-in solar kits in the UK — and most of the experts I spoke to agreed.

"They are the fundamental great equalizer," says Octopus' Alex Schoch on plug-in batteries. "It’s such an important thing for renters because you can then take it with you to your next place," he adds.

"I think in the next couple of years we will see plug-in batteries really be the transformational scale deployment. I think it has the potential of being a mass market thing even faster than solar," he predicts.

Windfall Energy's Rob Hallifax naturally agrees when comparing plug-in batteries to their solar equivalent. "There are 28 million homes in the UK and about half of them are either rented or flats and small homes. So more people could get them, millions, and there’s also the benefit to the grid and to the system," he says.

There is one other obvious comparison with an accessory that's cheap, easy to use and promises to save you money. "We use air fryers as quite a good example. Four or five years ago they just came from nowhere and suddenly half the country has one," he says.

But wouldn't an 'air fryer' level of popularity also cause a problem for plug-in batteries? After all, a lot of their money-saving potential comes from tapping into today's so-called 'delta' between cheap-rate and peak-rate electricity. If plug-in batteries help to solve the imbalance of today's grid demand — and tariffs are adjusted to reflect that — could that start to diminish their savings potential?

"I think yes and no," says Windfall Energy's Rob Hallifax. "So maybe in 50 years the whole grid will be sort of perfect. I think the fundamental thing is that if you have renewable generation, that's always going to be variable. That's just the nature of the world. And so somewhere in the system, storage has to be part of it," he adds.

Octopus Energy's Alex Schoch agrees that such a change would be a long way off. "In theory, yes." he says in response to my pessimistic scenario. "But I would actually say the length of time here is measured in decades, not in a sub-decade quantum," he adds.

However, he does note that a similar process is already happening. "We've had such an explosion of solar in the UK over the last few years that now during Spring and Summer, a lot of the cheapest wholesale price electricity times are actually late morning, early afternoon, mid afternoon, and no longer overnight," he notes.

Charging ahead

The legalisation of plug-in batteries in the UK appears to be a matter of 'when' not 'if'. As a flat owner in south west London with no roof and only a limited appetite for plug-in solar, I'm right in the target market — and will certainly be interested when that moment comes.

But it also won't be an impulse buy where I snap up the first thing I see Amazon. "The biggest pitfall to avoid is making decision on price alone," says Anker's Kelvin Cao. "Now that plug-in solar has regulatory approval, the UK market will attract a wave of low-cost imports, some of which will be excellent and some of which will not. This will be a similar problem once the plug-in batteries are legalised," he warns.

"A battery that cuts corners on cell quality, protective engineering and compliance with applicable safety standards might look more attractive on its price tag, but it will not deliver the same reliability over the 10 to 15 years that a household should reasonably expect," he adds. In other words, buying cheap could backfire when it comes to savings.

So what exactly should you look for when plug-in batteries are legalised? "As a baseline, consumers should look for durable LFP battery cells, a high cycle life, robust protection against weather and corrosion, and integrated safeguards against electrical and thermal risks," Kelvin Cao says.

"They'll probably also say that the product must be listed on the Energy Networks Association (ENA) Type Test Register to demonstrate that its protection settings meet G98 requirements," adds Windfall Energy's Rob Hallifax.

A real-world view

A large number of early adopters are already getting a taste of the benefits of a battery-only setup. One of those is TechRadar contributor Mark Pickavance, who wrote our EcoFlow Stream Ultra X review (which is well worth a read).

I caught up with him to see how it's going and he continues to be impressed. He told me that his monthly energy costs are down by about £40 a month with his setup (which was installed with the help of an electrician), and you could get most of that from a single Ultra X.

The only problem is that this stuff can get addictive. "I started with the premise of using just a battery, but once you have one the logical progression is solar. However, for people renting, it's the ideal solution, and if you use an Economy 7-like tariff (Octopus Go), you can take a chunk out of your costs," he said.

The arrival of plug-in solar from August could, then, be a good dry run of what to expect when plug-in batteries arrive. The big differences between residential buildings between Germany and the UK could mean plug-in solar doesn't quite take off in the same way in the UK, but Anker's Kelvin Cao remains bullish.

"This is no longer a niche movement. Germany passed one million officially registered plug-in solar systems in 2025, with around 430,000 new systems registered during that year alone," he notes. If plug-in batteries follow a similar pattern in the UK, that could have big consequences for energy bills — and the UK's grid as a whole.

There's no mistaking the growing momentum behind small-scale, low-cost solar panel installations: panels you can plug into a standard wall outlet, without the expense, time, or paperwork of a full rooftop installation.

Now widely established in Europe (where the tech is best known as 'balcony solar'), we're starting to see a wave of American states move towards legalizing these plug-in panels as well. Utah was the first in 2025, and there are now proposals in 30 other states to make the devices available to buy.

They're perfect for renters as well as homeowners. You can take them with you if and when you move. Additionally, they offer some respite from the energy price crisis, and they're becoming increasingly widely available.

At the same time, we're seeing a record number of homes in the US installing battery energy systems, hooked up to rooftop solar or the grid — another way to reduce electricity costs and provide a backup for a creaking national power system. Here's what's happening with home energy tech right now, and where it's going next.

Plug-in solar: the state of play

Utah set the ball rolling for plug-in solar in the US by passing House Bill 340 in March 2025. It means that portable solar panels or rooftop panels — up to a total capacity of 1,200 watts (typically four roof panels) can be plugged into a regular outlet. These panel systems use an integrated microinverter to convert the panels' DC output into household AC, ready for use.

In the default setup, this means the energy produced by plugged-in 'balcony' panels will be taken up by your home appliances first, before they try to access the grid. While battery connectivity is possible, the general idea is that the energy isn't stored anywhere — it's just pushed into your home for use as needed.

Estimates suggest you can shave around 10% off your electricity bill, though this will vary a lot depending on factors like electricity prices and how much sunshine you get. You can think of it as a way of getting a sizable chunk off your bill, rather than something that's going to replace the power grid entirely. The kits themselves start at around $500 and go up from there.

Now other states are following Utah's lead. According to The Cool Down, more than 30 states have drafted some form of bill, while six states have already enacted related laws. You can keep track of what's happening via the Bright Saver tracker, which provides updates for each state and a handy interactive graphic showing the overall picture.

You'll notice quite a few states are at the 'deferred' stage, which means the decision on legislation has been put off to a later date. A lot of these deferrals are on safety grounds: the argument from utility companies is that feeding power into household wiring (rather than just taking it out) comes with risks, and that more needs to be done to protect both consumers and the power grid.

The UL 3700 safety certification, freshly put into place this year, should help here. Plug-and-play solar panels with this certification attached will have built-in safeguards to prevent systems from being overloaded and to stop power flowing back into lines. It's a badge to look for if you're buying this kind of equipment.

Home battery installations

Home battery tech is separate but related, and as Ars Technica reports, records are being broken for battery installations: 673 megawatts of energy storage were brought online in the first quarter of 2026, the highest that figure has ever been.

The key driver here matches up with plug-in solar: rapidly rising electricity costs. The batteries can either store energy from rooftop solar panels, or bank electricity at off-peak times ready to be used during on-peak times. Plus, these appliances offer protection against power outages and help save money.

Unlike plug-in solar panels, home batteries do require a professional installation, the cost of which can be added on top of a typical $10,000-and-up price of the battery itself. It'll take years to pay that back in savings, but it will be paid back — it depends largely on whether you're using solar panels, how many panels you're using, and your home's electricity demand.

There are even moves to tap into this stored energy to help meet the huge energy demands of AI. Companies including Tesla will pay you on an ongoing basis if you allow them to control when your battery charges up and releases power — helping to manage stress on the overall power grid, especially during peak times.

While today's plug-in solar systems aren't designed to connect to big home batteries directly — though they can certainly operate alongside each other in the same home — a selection of them now come with their own portable batteries. As both technologies get more common and issues like safety certifications get sorted out, it's certainly plausible that future plug-in solar kits will be able to feed home batteries.

With the potential cost savings, worries over power grid reliability, and the increasingly convenient (and legal) ways to get all of this set up, it's no wonder that plug-in solar and battery energy technology is growing in popularity — and all the signs are that these devices are likely to become much more widely used in the near future.