Solar batteries, UK 2026.

Why fit a battery at all

Without a battery, your panels export surplus to the grid at the Smart Export Guarantee rate (3–15p/kWh). With a battery, you self-consume that electricity at 27–30p/kWh equivalent — a 2–10x saving on every stored kWh.

The bigger win in 2026 is off-peak import arbitrage. With tariffs like Octopus Go (7p/kWh overnight), you charge the battery cheap at night and run the house off stored energy during peak hours. Even if your solar doesn't charge it fully, the tariff difference pays back.

The battery brands worth knowing

Tesla Powerwall 3

13.5 kWh usable, built-in inverter, 11.5kW peak / 5kW continuous. Around £10,500 installed. Industry-leading cycle life and warranty (10 years unlimited cycles). Overkill for a 4kW solar setup; ideal for 6kW+ with future EV charging.

GivEnergy All-in-One

13.5 kWh usable, integrated 5kW hybrid inverter. £7,500–£9,000 installed. UK-designed, excellent app, 12-year warranty. Most popular mid-market choice in 2026.

Sunsynk Ecco 5.32

5.32 kWh stackable modules. £3,500 per module installed. Great for incremental upgrades — start with one, add more as budget allows. 10-year warranty.

Huawei LUNA2000

5 or 10 kWh modules. £4,000–£7,500 installed. Strong monitoring app, integrates well with Huawei solar inverters. 10-year warranty.

SolaX Triple Power T58

5.8 kWh modules, stackable up to 23.2 kWh. £3,800 per module installed. Solid value; widely installed; 10-year warranty.

How big a battery do you need?

The rule of thumb: match battery capacity (kWh) to your evening electricity use (kWh), not your solar generation.

Portable alternative: plug-and-play power stations

If a £7-10k installed battery is too big a commitment, portable power stations are the gateway drug. Charge them overnight on Octopus Go (7p/kWh), run the house off them during peak hours. Capacity tops out around 3kWh per unit, and they need no installer.

• EcoFlow DELTA 2 (1024Wh) — best-selling expandable option
• Jackery Explorer 1000 v2 — simpler, cleaner plug-and-play
• Anker SOLIX F1500 — 10-year warranty, premium build

See our full portable power station roundup for detailed picks.

Payback

A 10 kWh battery in a typical UK home saves £600–£1,100/year(mix of self-consumption + off-peak arbitrage). At £7,500 installed that's a 7–12 year payback. Warranty is typically 10–12 years, so you'll see net gain over life.