Plug-in solar: kits, cost, and is it legal
For renters, leaseholders, and anyone who can't fit a full roof system — a plug-in or balcony kit generates real savings on a much smaller budget. Work through the steps below to size a kit, understand how it connects, and get a full plan.
Why plug-in solar?
A plug-in or balcony solar kit is a small (typically 400–800W) panel-and-microinverter system that plugs into a normal socket rather than being wired into your consumer unit by an MCS installer. It's the fastest, cheapest way into home solar — here's the headline case:
- Cost: £300–1,200 for the kit, all-in
- Savings: £79–190 a year on a typical UK electricity bill
- Payback: roughly 3–8 years
- No roof access needed — mounts on a balcony rail, garden wall, or outbuilding
- No Smart Export Guarantee (SEG) income— SEG requires MCS-certified installation, which plug-in kits can't obtain, with one partial exception: Octopus Energy currently accepts some plug-in setups on certain tariffs
If you rent, have a leasehold agreement that rules out roof work, or just want to test whether solar is worth it before committing to a bigger project, this is where to start.
Plug-in vs full install vs DIY roof: what you actually get
The three routes to home solar sit at very different points on cost, effort, and return:
| Plug-in kit | DIY roof install | Full install | |
|---|---|---|---|
| Cost | £300–1,200 | £2,500–3,800 | £6,000–8,000 |
| Annual saving | £79–190 | £450–660 | £450–660 |
| Total saved after 10 years | £790–1,900 | £4,500–6,600 | £4,500–6,600 |
| Total saved after 20 years | £1,580–3,800 | £9,000–13,200 | £9,000–13,200 |
| Total saved after 30 years | £2,370–5,700 | £13,500–19,800 | £13,500–19,800 |
| Payback | 3–8 years | ~8–10 years | 8–12 years |
| Roof access needed | No | Yes | Yes |
| SEG-eligible | No (bar the Octopus exception) | Only if MCS-certified on sign-off | Yes |
| Self-install legal? | Yes, for a compliant kit | Panels/mounting only — electrician for final connection | N/A — professionally fitted |
Cumulative totals are the annual saving range multiplied by years — they don't account for panel degradation (typically ~0.5%/year) or rising electricity prices, so treat them as a simple like-for-like comparison between the three routes rather than a precise long-run forecast.
See our DIY solar installation guide for the full DIY-roof breakdown. Plug-in solar is the only one of the three you can self-install end to end: as of 27 August 2026, compliant kits can be self-fitted in Great Britain without an electrician, though you still need to notify your electricity network operator either way. Adding a battery to a plug-in kit sits outside this legal framework — the government's Interim Product Specification covers grid-tied generation only, not stationary storage, so a bundled battery may need separate consideration.
Own your home? Full solar could save you more
Plug-in solar is capped at 800W and can't earn Smart Export Guarantee (SEG) payments — it's built for renters and leaseholders who can't fit a full system. If you own your property, a full roof install earns SEG income (currently around 13p/kWh exported — supplier-dependent) on top of the electricity you use yourself (worth 26p/kWh at the current price cap), which plug-in solar can't access at all. A full install also currently qualifies for 0% VAT until 31 March 2027, saving roughly £1,100 on a typical 4kWp system. If you're in Scotland, Home Energy Scotland offers up to £6,000 of funding for solar PV — part cashback grant, part interest-free loan — though only when solar is bundled with a heat pump or high heat retention storage heaters, not as a standalone solar application.
| Plug-in solar | Full install | |
|---|---|---|
| Upfront cost | ~£300–1,200 | ~£6,100+ |
| SEG export income | Not available | Yes, with an MCS-certified install |
| System size cap | 800W | No cap — sized to your roof |
Plan your kit in 4 steps
- 5 min
Assess your space
Balcony, garden, or wall space and socket access — this determines what size kit makes sense.
Start step 1 - 10 min
Choose your kit
Plug-in solar is sold as a complete panel + inverter + cable system. Pick one, and add battery storage if you want it.
Start step 2 - 5 min
Is it legal, and who connects it?
Self-install is now legal for compliant kits — what qualifies, what still needs G98 notification, and what falls outside the rules.
Start step 3 - 5 min
Your plan
Your chosen kit, estimated savings, and how to get it sourced or connected.
Start step 4