Best plug-in solar battery in the UK: four to buy and what each costs per kWh

No battery can be plugged into a socket under the UK's plug-in solar rules, so each one here needs an electrician. On 14 November 2026 the best value per kilowatt-hour was EcoFlow STREAM 5000 and Anker SOLIX Solarbank 4 E5000 Pro, at about £318 per kWh. The cheapest way in was the 1.92 kWh EcoFlow STREAM Ultra at £699.

Solar batteries for the UK compared

Four systems take solar panels directly and are sold to UK homes by the maker. We rank them on what you pay for each kilowatt-hour of storage, so different sizes compare fairly. Prices are before installation and were read on 14 November 2026.

The capacities and solar inputs are the makers' own figures from their UK pages, checked for our reviews between 21 and 30 September. The EcoFlow STREAM AC Pro, a 1.92 kWh add-on with no solar input, costs £659, about £343 per kWh, and joins an Ultra when one box isn't enough.

How to choose the right battery for your solar panels

Start with the electricity you use after dark, because that sets the storage capacity you need. A home that uses 4 kWh between tea time and bed gains little from a 5 kWh battery. Then count your solar panel wattage against each system's input limit: eight 450 W panels add up to 3,600 W, which is over the 2,000 W units. Finally, ask your electrician which inverter the system uses and what output it will be set to, since your network operator needs that figure.

Price per kilowatt-hour is a guide, not a verdict. A larger battery only pays back if your panels fill it, and an energy management app that lets you choose when it charges and discharges matters on a time-of-use tariff.

Best solar battery for your home

• Small budget, small evening load: the STREAM Ultra at £699. It is 23.1 kg, the easiest to carry, and takes up to 2,000 W of panels.
• A few panels and a bigger evening load: the STREAM Ultra X at £1,499 holds twice as much in one box, at 38.8 kg. Our Ultra X review sets it against the Ultra.
• A large roof or a lot of panels: the 5.024 kWh STREAM 5000 or Solarbank 4 Pro, both of which accept 5,000 W of panels. The STREAM 5000 review covers its expansion packs.
• More storage later: add a STREAM AC Pro to an Ultra, or an Anker expansion pack to a Solarbank.

EcoFlow or Anker for a large system

The two 5.024 kWh systems store the same amount and take the same solar panel input. Anker lists IP66 and a 10 ms switchover to backup, and a 10-year warranty. EcoFlow lists IP65 and a 10-year warranty. Choose on price on the day, the app you prefer and who your electrician is happy to fit.

Anker's Black Friday sale was already running on its UK store on 11 November, ending on 30 November. Read the Solarbank 4 Pro review or our EcoFlow versus Anker comparison before you buy.

What installation involves

EcoFlow supplies the STREAM units with a stripped-end cable that must be hardwired by a registered electrician, and Anker says a qualified electrician must hardwire the Solarbank 4 Pro. Your electrician also tells your network operator under the G98 process. Ask for a written quote that names the register reference of the unit. EcoFlow's STREAM batteries, for example, are on the ENA register as energy storage devices, not as plug-in solar. Our electrician guide explains when one is needed.

Will a battery pay for itself?

The best UK evidence we've found is one owner's year on an EcoFlow STREAM Ultra plus AC Pro, on four fence-mounted panels: £335.13 saved over 365 days, against about £2,100 for the system. EcoFlow supplied the units, and part of the saving came from charging on a cheap overnight tariff. Anker quotes up to £770 a year for the Solarbank 4 Pro, based on a cheap overnight tariff and plenty of solar, with installation left out. We haven't measured either figure.

Batteries left off this list

• Zendure SolarFlow sits between your panels and microinverter and works with the inverter you already own. Our review found patchy UK availability and carries July prices that we haven't rechecked, so it isn't ranked. See our Zendure SolarFlow review.
• DJI Power 2000 is a portable power station with an optional grid-tied mode, so it's a different product. It is on the ENA register as an energy storage device.
• Jackery Navi 2000 isn't sold in the UK, so it isn't a choice.

Where to buy

EcoFlow sells direct through its UK store and through its own listings on Amazon UK. Anker sells direct and through Amazon UK. We don't print Amazon prices, so open the listing to compare.

Frequently asked questions