Plug-in Solar UK 2026: The Complete Post-Legalisation Guide

What Just Changed

For years, plug-in solar sat in a UK regulatory grey area. Other European countries (Germany, the Netherlands, Spain, Austria) normalised it years ago, and millions of small systems were installed on balconies, walls, and sheds. The UK held back, partly because our wiring regulations didn't have a category for it.

That changed in March 2026. Energy Secretary Ed Miliband announced on 24 March 2026 that plug-in solar would be legalised, and on 15 April 2026 the Institution of Engineering and Technology (IET) published BS 7671 Amendment 4 bringing it into force. The Department for Energy Security and Net Zero (DESNZ), working with the IET and the Energy Networks Association (ENA), built the regulatory framework on top of a safety study by Arceio Limited commissioned in October 2025, which concluded that the risks of plug-in solar on UK ring-main circuits are manageable with appropriate product standards.

The headline facts:

• 800W maximum output per home. Anything bigger goes through the G99 process (slower, may need DNO approval).
• CPS-registered electrician install required until the BSI product standard publishes (expected July 2026). Until then, plug-and-play installation directly into a standard socket is not legally compliant.
• G98 notification within 28 days of install. Not permission, just a notification to your Distribution Network Operator that the system is there.
• BS 7671 Amendment 4 sets the wiring requirements; the BSI standard (when published) will define which products can be plugged directly into a 13A socket.

This is genuinely new. Most UK content older than April 2026 was written under uncertainty and is now out of date.

Do You Qualify? A Quick Decision Framework

Before you spend £500-800, work through this list:

• Do you own your home, or have your landlord's written permission? The installation involves work at the consumer unit, which legally requires the homeowner's consent. If you're a leasehold flat owner, check your lease for clauses on alterations.
• Have you got somewhere to mount the panels? Balcony railing, garden wall, shed roof, garage roof. South-facing is best but east or west works at 80-90% of optimal. North-facing isn't worth the effort.
• Can you get to a CPS-registered electrician within the next month or two? Mandatory step (for now). Budget £200-400 for the install.
• Is your home's daytime electricity use high enough to make self-consumption meaningful? Working from home, retirees, families with kids home in the day: yes. Empty house from 8am to 6pm: a battery pays back faster.

If three of those four work for you, plug-in solar makes sense. If none do, wait until July 2026 when (in theory) you'll be able to buy a certified kit and self-install.

How Plug-in Solar Actually Works

The mechanics are similar to rooftop solar but smaller. The panels generate DC electricity. The microinverter (usually mounted right next to the panels) converts that DC to mains-compatible AC at 230V. From there, the AC current feeds into your consumer unit and your appliances draw from it first, before falling back to the grid. Any surplus exports to the grid via your smart meter and earns you a Smart Export Guarantee payment if you've got a SEG tariff set up.

The microinverter is the key bit. Unlike rooftop string inverters that handle 4-10 kW of total system power, a microinverter is small, handles 600-800W, sits outside the house with the panels, and has built-in safety isolation. UK-legal microinverters meet the G98/G99 anti-islanding requirement: if the grid drops, the microinverter shuts off within two seconds. That's why plug-in solar doesn't help during a power cut.

Calculate Your Payback

Pick your system cost, install cost, and whether you want a battery. The calculator uses realistic UK yield (~750 kWh/year for an 800W system), current Ofgem cap rates, and average SEG tariffs.

A few notes on the maths:

• Annual generation is conservative: 0.95 kWh per watt per year for an average UK installation. Northern UK reduces; south coast adds.
• Self-consumption sits around 30-40% without a battery and 70-80% with one. Working from home pushes the no-battery figure higher (45-55%) because you're using the solar as it generates.
• Export tariffs vary widely. Octopus Outgoing pays 12p/kWh (as of March 2026, down from 15p). Basic SEG offers from most suppliers are 4-5p. Worth switching if your tariff lags.
• Panel degradation is about 0.4% per year, which I've ignored for simplicity. Real lifetime savings are 5-7% lower than the headline calculator output.

What's Actually In Stock Right Now

Six weeks after the regulatory change, UK supply is still catching up. Most of the brands you'd expect (Hoymiles, APsystems, Growatt NEO, Anker SOLIX, Marstek, Zendure) are currently out of stock on Amazon UK or only stocked through specialist installers. The exception is EcoFlow, which has had UK distribution running since 2024 and offers three options through Amazon (with 4-5 week dispatch times due to demand).

The 3 Currently Buyable Picks

The bare microinverter is the cheapest way in if you're already shopping for panels separately or already own them. 800VA output, dual MPPT inputs (16-60V DC per channel, so you can wire two different-sized panels), IP67 weatherproof, 2.4GHz WiFi monitoring through the EcoFlow app. The 10-year warranty matches Hoymiles and Anker, which surprised me when I checked: EcoFlow's UK STREAM line genuinely competes on warranty terms.

If you've got a Delta 2 or River 2 sitting around as a backup power station, the STREAM also doubles them up as battery storage for the solar setup. That's a clever EcoFlow ecosystem play.

Buy this if: you want the cheapest entry, you already have panels (or want to buy them cheaper separately), and you're comfortable matching a microinverter to your own panels.

The kit puts everything in one box: 800VA microinverter, two 400W rigid panels (23% efficient, IP68, rated for 130 mph winds), lattice balcony brackets. If you don't already have panels, this is the right pick because the compatibility is guaranteed and the brackets fit standard balcony railings out of the box. EcoFlow's own numbers claim 858 kWh of generation and around £115 of annual savings — our calculator above is slightly more conservative at ~£75-90 per year because we apply the realistic 35% self-consumption rate without a battery.

£499 is the EcoFlow member price; non-members pay £579. Membership is free with an EcoFlow account at the time of writing. The other catch is delivery: like the bare microinverter, Amazon's currently quoting 4-5 weeks. Order now if you want it installed before late summer.

Buy this if: you don't already have panels and you want the easiest path from order to working system.

Adding a 1.92 kWh LiFePO4 battery to the system makes a meaningful difference. Self-consumption rises from roughly 35% (no battery) to 75% (with one), which means more of your generation displaces 26.55p grid imports instead of being exported at 4-12p. Over 25 years that's a substantial extra saving.

The AC Pro stacks up to six units giving a maximum 11.52 kWh of storage, so it's an upgrade path rather than a dead end. 6000 cycles to 70% capacity is the LiFePO4 spec, which is realistically 15+ years of daily use. The unit also has built-in self-heating that kicks in below 5°C: useful for unheated balconies, sheds, or porches where the battery would otherwise lose capacity in cold weather. Smart AI energy management optimises when to charge from solar, discharge to the house, or export to the grid based on your tariff and usage.

Note the battery does NOT give you grid backup during a power cut: G98 anti-islanding still applies even with storage attached. Storage is for shifting solar from midday to evening, not blackout backup.

Buy this if: you're in for the long haul, you want to use solar after dark, and you're prepared to spend £290 more than the kit for the storage benefit.

Brands to Watch (Currently OOS)

If supply was unconstrained, these would also be on the list. Worth checking back over the next 8-12 weeks as UK stock returns:

• Anker SOLIX Solarbank 2 E1600 Plus (£1,199 last seen) — integrated 1.6 kWh battery + microinverter in a single weatherproof unit. The most elegant all-in-one but currently OOS on Amazon UK.
• Anker SOLIX Balcony Power Station Pro — premium full-kit including 1.92 kW MI + 2x 1.6 kWh storage + 4x 445W panels. Out of stock.
• Hoymiles HM-800 / HMS-800W-2T — proven microinverter brand with 10-12 year warranty. UK distributor listing 404'd; bare unit OOS.
• Growatt NEO 800M-X — IP67 microinverter with WiFi + PLC monitoring. Currently OOS.
• BENY 800W Microinverter — German-market favourite at £147 last seen. OOS.
• Marstek B2500 — 2.24 kWh expandable battery designed specifically for plug-in solar. OOS.

As of late May 2026, EcoFlow is the only brand with a working UK Amazon supply chain. That'll change over the summer. Worth bookmarking this page and checking back.

The Install Process Step by Step

Until the BSI product standard publishes (July 2026), every install needs a CPS-registered electrician. Here's what to expect:

1. You order the kit (or microinverter + panels separately). Delivery is currently 4-5 weeks for EcoFlow STREAM units.
2. Mount the panels. Balcony railing, garden wall, shed roof, garage roof. South-facing 30-45° tilt is optimal. Use the included brackets if it's a kit; otherwise buy panel mounts that match your surface.
3. Mount the microinverter. Goes outside, near the panels, IP67-rated so weather doesn't matter. Connect panel DC cables to the microinverter inputs.
4. Electrician hardwires the microinverter output to a dedicated circuit on your consumer unit. This is typically a 30-90 minute job. They'll isolate the consumer unit (so everything plugged in goes off briefly) while they work.
5. Electrician issues an Electrical Installation Certificate for the work. Keep this; you'll need it for the G98 notification.
6. You (or the electrician) submit the G98 notification within 28 days. Each DNO (UK Power Networks, SSEN, Western Power, Northern Powergrid, Scottish Power, NIE Networks) has a slightly different form. It's a notification, not a permission request.
7. Set up the app + monitor generation. EcoFlow STREAM has WiFi + app. You'll see daily/monthly kWh and export figures in real time.

Total realistic install timeline: 5-7 weeks from order to working system, including the 4-5 week Amazon dispatch wait and a couple of weeks to schedule the electrician.

What NOT To Do

• Don't plug a microinverter into a 13A wall socket and call it done. Not legal until the BSI standard publishes. Even then, only certified kits can be plug-and-play.
• Don't exceed 800W per home. Two 600W microinverters on the same property is over the limit. If you want more than 800W, you need a full G99 application and probably a proper rooftop install instead.
• Don't skip the G98 notification. Penalty is mostly that your DNO may not approve future changes without it. The form takes 15 minutes.
• Don't buy a non-CE-marked microinverter from an unfamiliar brand. Plenty on AliExpress; almost none meet UK/EU regulatory standards. The 5-year warranty also vanishes the moment you import unofficially.
• Don't expect to power your house during a blackout. G98 anti-islanding shuts the system off within 2 seconds of a grid drop. Battery storage included.
• Don't mount panels somewhere they'll be in shade for half the day. Shading on one panel disproportionately reduces total output even with the microinverter's per-panel MPPT.

Plug-in Solar vs Rooftop Solar

The honest summary: rooftop solar is a better economic deal if you own a house with a usable roof. Plug-in solar is for renters, flat dwellers, and anyone who can't fit a full system. The payback period is similar (5-8 years vs 8-12) but rooftop generates 5x more electricity, so lifetime savings are far higher. If you can do rooftop, do rooftop. See our solar panel costs UK guide for the maths.