Plug-in solar kits are arriving in UK shops in 2026. An 800W kit costs £419–£499, installs in under two hours without an electrician, and reduces your electricity bill by £125–£250/year depending on your tariff and self-consumption. The maths works. Here's how.
The basic case
800W of panels generate 580–780kWh annually in the UK. At the current standard rate of 24p/kWh, self-consuming 650kWh saves approximately £156/year. At a kit cost of £499, payback is around 3 years. Panels last 25+ years. The investment is positive by a wide margin.
Why the tariff matters
On a standard flat tariff, every kWh you self-consume saves you 24p. On Octopus Agile, the picture is more nuanced — and more favourable. Your panels generate during the day when Agile rates are moderate. But the real value comes from using a battery to store solar and discharge during the 25–35p evening peak. The tariff choice can improve your annual saving by 30–60%.
Switch to Octopus Agile and get £50 credit →
Which kits to buy
For detailed product reviews, visit our sister site Sun On Tap. The short version:
- EcoFlow STREAM 800W (£499) — best overall experience, bifacial panels, polished app
- Anker SOLIX RS40P (£419) — best value, Amazon-native, solid hardware
- Hoymiles HM-800 DIY build (£280–£350) — cheapest route, source your own panels
The optimal setup
Step 1: Switch to Octopus (£50 credit). Step 2: Get a smart meter installed (free). Step 3: Switch to Agile. Step 4: Install your plug-in solar kit. Step 5: Add a battery. Combined saving: £200–£400/year versus a standard tariff with no solar.