Plug-in solar panels set up outside a UK home

Why plug-in solar buyers should care about their tariff

An 800W plug-in solar kit generates 580-780kWh annually in the UK. On a standard flat-rate tariff, every kWh you self-consume saves you roughly 24p. But on Octopus Agile, the picture is more nuanced — and more favourable.

Agile prices electricity in half-hour slots. During sunny midday periods when your panels are generating, Agile rates are often below 10p/kWh — meaning the grid electricity you're displacing was already cheap. The real value comes from using solar generation to avoid the expensive 4-7pm evening peak, when Agile rates can reach 30-50p/kWh. If you have a plug-in battery (like the Anker Solarbank or Zendure SolarFlow), you can store midday solar and discharge it during the evening peak — effectively saving 30-50p per kWh instead of 10-15p.

What this means in practice

A plug-in solar kit on a standard tariff saves approximately £125-£156 per year. The same kit paired with Octopus Agile and a small battery can save £180-£250 per year, because you're displacing expensive evening electricity rather than cheap midday electricity. The tariff choice can improve your annual saving by 30-60%.

How to get started

If you're buying or considering plug-in solar, switching to Octopus first makes sense — you get the £50 referral credit immediately, and you're on the right tariff platform to maximise your solar investment when the kit arrives.

  1. Switch to Octopus with £50 credit
  2. Request a smart meter (free, Octopus arranges installation)
  3. Switch to Agile once your smart meter is installed
  4. Install your plug-in solar kit
  5. Add a battery if you want to maximise evening savings
Solar panel in a UK garden

Which plug-in solar kits work best with Agile?

Any 800W plug-in solar kit benefits from Agile, but kits with battery integration benefit most. The EcoFlow STREAM Pro (with integrated battery) and the Anker SOLIX RS40P (paired with a Solarbank 2 Pro) are the strongest combinations for Agile users.

For detailed kit comparisons, visit Sun On Tap — our dedicated UK plug-in solar review site.