4 Billion Years On

UK Plug-in Solar Guide

Daily-updated UK Status, Products & Costs

The 5-second verdict

13 May · 10:05
Legal in the UK?
Partially
See timeline below
How much?
From £349
Typical 800W kit · £70-£175/yr saving
Can I install today?
~Mid July
Buy → plug in → notify your DNO (G98)
Payback period
3–4 yrs
Depends on location, usage & tariff
800W
The legal limit
800W AC max output per home, via a standard 13 A socket
Panels can total more on the DC side – the micro-inverter clips output to 800W AC. The same limit applies whether you have solar, a battery, or both.
  • Solar only
  • +Solar + battery
  • Battery only

The 1-minute update

Legal & in the shopsmedium confidence
July 2026(~2 months away)

The BSI plug-in solar product standard is expected around July 2026, which should align with major retailers routinely stocking compliant kits.

UK regulation timeline

past → future
  1. Mar 26
    Legalisation announced
  2. Apr 26
    BS 7671 Amend. 4 live
  3. Jul 26
    Legal & in the shops
  4. Oct 26
    Amend. 4 transition ends
  5. Apr 27
    Simplified SEG

About this page. A daily- refreshed, impartial UK guide to plug-in solar (also called balcony solar or Balkonkraftwerk) covering the legal status, the kits you can actually buy today, prices and payback, and how to pair – or replace – panels with a battery on a smart tariff. We re-research the regulations, products and prices every morning using Gemini against primary UK sources (gov.uk, BSI, Ofgem, mainstream UK press) so the figures you see below are never more than 24 hours old. We are editorially independent: any retailer link is disclosed and never affects what we list or rank.

Where things stand today

Legal in the UK?
Partially

BS 7671 Amendment 4 published, BSI product standard pending.

Verified 13 May 2026

Products on shelves?
Yes

Several plug-in kits are available from manufacturers and retailers.

Verified 13 May 2026

SEG export payments?
No

SEG requires MCS certification, not available for DIY plug-in installs yet.

Verified 13 May 2026

DNO notification needed?
Yes

G98 notification is mandatory within 28 days of installation.

Verified 13 May 2026

What is plug-in solar?

How plug-in solar worksSunlight hits a solar panel which feeds DC power into a combined micro-inverter and optional battery unit. The inverter converts the DC into 230 V AC and pushes it through a standard three-pin plug into the home wiring. The optional battery stores any excess for use later. The grid invisibly tops up whatever isn't being supplied.SUNfree fuelPANEL~400-880 W DCDC → AC INVERTER800 W max output+BATTERYoptional · 1-2 kWhINVERTER + BATTERYsingle 13 A plugYOUR HOMEself-consume firstGRIDtops up the rest

← swipe to see full diagram →

Most UK kits combine the inverter and (optional) battery into one box that plugs into a single 13 A socket. The grid invisibly tops up whatever isn't being supplied.

⚡ A battery-only version skips the panel entirely — useful for time-shifting cheap overnight electricity (e.g. on Octopus Flux) into peak hours.

Plug-in solar - sometimes called balcony solar, DIY solar, or by its German name Balkonkraftwerk - is a small photovoltaic system you install yourself and plug into a regular three-pin socket. A typical kit is one or two solar panels, a micro-inverter that converts DC from the panels into 230 V AC, and a standard UK plug.

Once plugged in, the inverter pushes electricity into your home's wiring. Anything you happen to be using at that moment - the fridge, the router, the kettle, your laptop charger - takes that solar electricity first, and the grid only tops up what's left. It's not a backup battery: when the panels stop producing, the grid takes over invisibly.

The legal limit in the UK is 800 watts of AC output per circuit. That's roughly enough to run an always-on "base load" - fridge, freezer, internet kit, a few standby devices - on sunny days. Most kits use one or two panels of around 400-450 W each, so panel input can be slightly higher than 800 W (the inverter clips the excess).

Plug-in solar will not power your house in a power cut. The inverter is required to detect a grid outage and shut off automatically ("anti-islanding") to protect engineers working on the network. To run essentials in a blackout you need a separate battery system with off-grid mode.

You do not need solar panels at all to benefit from the 800 W plug-in framework. A plug-in battery on its own - such as the EcoFlow STREAM AC Pro or a Zendure AIO 2400 - plugs into the same 13 A socket and pushes up to 800 W AC into your home wiring. The real advantage comes with a time-of-use tariff like Octopus Flux or Agile: charge the battery overnight when electricity is cheapest (often under 10 p/kWh), then discharge it during the expensive evening peak (sometimes 35-45 p/kWh). Done well, this "time-shifting" can cut your bills even without a single solar panel on site. Add panels later and the battery stores any daytime generation you would otherwise have exported for free.

Is it legal in the UK yet?

Is your setup legal?

self-check
  • Sub-800 W AC kit, sold by a UK retailer
    Compliant with BS 7671 Amendment 4 and the upcoming BSI product standard. Plug straight into a normal 13 A socket.
  • You notify your DNO within 28 days (G98)
    Free online form, no approval required. We have a postcode → DNO finder lower down the page.
  • You tell your home insurer
    A simple note on the policy. Most insurers add it for free; not telling them gives grounds to refuse a claim.
  • Renting? Tell your landlord first
    Plug-in solar is portable, so it usually falls outside "alterations" clauses, but the Renters' Rights Act 2025 expects written notice. Use our landlord letter template.
  • Imported "Balkonkraftwerk" with no UK certification
    Anti-islanding (EN 50549), earth bonding and BS 1363 plug compliance may not be guaranteed. Avoid generic Amazon/eBay listings without a UK importer.
  • Hard-wired into a dedicated spur
    That is no longer "plug-in" - it becomes notifiable electrical work and needs an electrician under Part P.

The legal landscape for plug-in solar in the UK is evolving. BS 7671 Amendment 4, which updates the wiring regulations to include stationary secondary batteries and generating sets, was officially published on 15 April 2026 and can be adopted immediately. This amendment lays the groundwork for plug-in solar by updating the framework for low-voltage generating sets and battery storage. The previous version, BS 7671:2018+A2:2022+A3:2024, will be withdrawn six months later, on 15 October 2026. However, Amendment 4 alone does not fully legalise plug-in solar for self-installation via a standard 13A socket. A separate BSI product standard for UK-certified plug-in devices, which will define approved device specifications and safety testing, is expected around July 2026. Until this product standard is published, no products are formally certified as UK-compliant. Despite this, some manufacturers are already selling kits in anticipation. Additionally, all plug-in solar systems with an AC output of less than 800W still require a G98 notification to the local Distribution Network Operator (DNO) within 28 days of installation. The government is working towards a simplified G98 registration pathway, potentially an online form, but this has not yet been confirmed. The next key milestone to watch for is the publication of the BSI product standard, expected around July 2026.

UK kits on sale today

Be wary of imported kits sold on Amazon and eBay aimed at the German or Spanish market. Some have been tested and found to lack proper UK anti-islanding (EN 50549), earth bonding for the panel frames, or BS 1363 plug compliance. Look for an explicit statement of UK compliance with BS 7671 Amendment 4.

Anker
SOLIX Solarbank 2 E1600 Pro
800 W AC
Unknown·1.6 kWh battery

Available in EU (€989) — not yet officially sold in the UK

Lidl
Parkside Plug-in Solar Kit
800 W AC
Unknown

Sold in Germany & EU; UK launch not yet confirmed — check lidl.co.uk

EcoFlow
STREAM Plug & Play Solar System
£349
800 W AC
PendingOut of stock

From £349 — choose panel size (2×400 W to 4×250 W) and bracket on EcoFlow's site

EcoFlow
STREAM Series Solar Plant
£1199
800 W AC
Pending·1.92 kWh battery

From £1199 for battery only (1.92 kWh) — add panels and extra batteries on EcoFlow's site

Amazon product-page links below use our Associates tag (UK/US/IE only, same as our book pages); other retailer links do not. Editorial choices are not influenced by it. See the full note at the foot of this page.

Top tip - a cheaper way to start

A plug-in solar kit pays back faster if you also time-shift your evening peak - but you don't necessarily need to spend £1,000+ on a dedicated home battery to get a good amount of benefit. A £100-£200 camping power station can soak up the excess your panels generate in the middle of the day (when no-one's home to use it), then run your TV, computer, games console (e.g. teenager's bedroom) during the 5-7pm peak - capturing some of the saving that a full grid/plug-in battery would.

Plug-in solar systems can't yet sell power back to the grid, so any midday excess your panels produce while the house is empty is simply wasted. A small battery turns that wasted generation into ~30p-per-kWh of avoided peak-rate import - which is why storage is the single highest-value upgrade you can layer on top.

If just 5% of the UK's 28 million households shifted 1 kWh a day off the evening peak, that's 1.4 GWh moved daily and roughly 200-300 MW shaved during 5-7pm - the output of a small gas peaker plant, gone. Full write-up here.

Cheap power stations on Amazon UK

Search links - we earn a small commission on Amazon UK purchases at no extra cost to you.

Regulations deep dive

BS 7671 Amendment 4

BS 7671 Amendment 4 (2026) was officially published on 15 April 2026 and can be implemented immediately. This amendment introduces a new chapter on stationary secondary batteries and updates requirements for low-voltage generating sets, which is crucial for plug-in solar. The previous version, BS 7671:2018+A2:2022+A3:2024, will be withdrawn on 15 October 2026, marking the end of the transition period. All new electrical work must comply with Amendment 4 after this date.

G98 connect-and-notify

G98 is an Energy Networks Association (ENA) engineering recommendation that outlines the requirements for connecting small-scale generators, including plug-in solar systems, to the public low voltage distribution network. For systems with an aggregate capacity of 16A per phase or less (which includes sub-800W plug-in solar), a G98 notification must be submitted to the Distribution Network Operator (DNO) within 28 days of commissioning. This is a 'fit and notify' process, meaning prior approval is not required.

BSI product standard

A dedicated BSI product standard for UK-certified plug-in solar devices is expected around July 2026. This standard will define approved device specifications and safety testing, which is essential for formal certification of plug-in solar kits. Until this standard is published, no products are formally certified as UK-compliant, although some manufacturers are selling kits in anticipation.

How the UK compares to Europe

The UK's approach to plug-in solar is aligning with other European countries. Germany, for example, simplified its plug-in solar regulations in May 2024 and had over 1.2 million cumulative installations by early 2026, with approximately 430,000 new systems registered in 2025 alone. Other countries like France and the Netherlands also have widespread adoption of plug-and-play solar systems. Belgium has also seen significant growth in micro-generation.

England, Scotland, Wales & Northern Ireland

Most of this guide applies UK-wide for product safety and BS 7671, but who you notify and the exact paperwork can differ. Use your own country's network operator (NIE Networks in Northern Ireland; GB DNOs elsewhere).

  • England & Wales

    BS 7671 (IET Wiring Regulations) is the usual technical rulebook for domestic electrical work across England and Wales. Plug-in solar still requires you to notify your distribution network operator under the GB connect-and-notify rules in Energy Networks Association documents (commonly referred to as G98 for sub-16 A single-phase equipment). Wales follows the same product-safety and market framework as England for CE/UKCA equipment of this kind.

  • Scotland

    BS 7671 is widely applied in Scotland for domestic installations. Scottish building standards govern structural or notifiable building work on your home; a freestanding or balcony plug-in frame is not the same as a fixed rooftop array, but you should still complete DNO notification and tell your insurer. Scottish properties use the same GB distribution networks (for example SP Energy Networks in southern Scotland) and the same style of connection forms as in England.

  • Northern Ireland

    Northern Ireland has its own electricity market oversight and NIE Networks as the distribution operator. Notification, export and small-scale connection paperwork can differ in detail from the G98-style process in Great Britain — check NIE Networks and the Utility Regulator for Northern Ireland for the current domestic microgenerator route before you plug in. Product safety (correct plug, inverter limits, instructions) still matters everywhere.

Plug-in vs rooftop

Plug-in solar is a great fit for some households and the wrong choice for others. If you own your roof, have an unshaded south-facing pitch, and use a lot of electricity, full rooftop solar will pay back faster per pound spent. Plug-in solar is the right answer if you rent, live in a flat or balcony, can't afford a £6,000+ install, or just want to dip a toe in.

Plug-in solarFull rooftop solar
Up-front costAround £400-£800 for an 800 W kitAround £6,000-£10,000 for a typical 4 kW system
Annual generation500-700 kWh in southern England3,500-4,200 kWh in southern England
Annual bill saving£70-£175£600-£1,000 (with a battery and a smart export tariff)
InstallationYou can do it yourself, no electrician requiredMCS-certified installer, scaffolding, planning
Get paid for export?Not yet - SEG simplification expected ~2027Yes, via the Smart Export Guarantee
Suitable for renters?Yes - portable, no permanent fix neededAlmost never - landlord and roof access required
Suitable for flats / balconiesYes - mounts on balcony rails or south-facing wallsNo

For full-roof solar costs, capacity, and SEG rates by country, see our energy dashboard and energy explainer.

Installation guide

  1. 1

    Check your consumer unit

    Your fuse board should be modern (RCD or RCBO protected). If you have an old re-wireable fuse board, ask an electrician to look at it before you plug in. Older houses with two-pin sockets won't work without an upgrade.

  2. 2

    Pick a sunny location

    South or south-west facing, unshaded between roughly 9 am and 4 pm in summer. A balcony rail, a south wall, a garden frame, a flat shed roof or a fence panel all work.

  3. 3

    Mount the panels securely

    Use the brackets supplied with your kit. Balcony rail brackets, ground frames and wall hooks are all available. Make sure the panels are tilted (typically 20-40 degrees) and cannot fall in high winds.

  4. 4

    Connect the micro-inverter

    The micro-inverter clips to the back of the panel or the mounting frame. Plug the panel DC cables into the inverter, then plug the inverter into a single dedicated 13 A socket. Do not daisy-chain through extension leads.

  5. 5

    Plug in and check

    Once plugged in the inverter takes ~60 seconds to detect the grid frequency, then begins exporting. Most kits include a Wi-Fi monitoring app showing live output.

  6. 6

    Notify your DNO (G98)

    Within 28 days you must tell your Distribution Network Operator that you have a generator under 16 A per phase. The form is free, online, and takes a few minutes. Use our DNO finder below.

  7. 7

    Tell your home insurer

    Most insurers will note the system on your policy at no extra cost. Don't skip this step: failing to declare a generator can give the insurer grounds to decline a claim.

Payback calculator

Annual generation
816 kWh
regional estimate
Annual saving
£146
@ 25.5 p/kWh
Simple payback
3.4 years
good

In the SW postcode area, an 816 kWh/year output (per our regional UK yield table) would save about £146 a year at today's 25.5 p/kWh unit rate, paying the system back in 3.4 years. Adjust the slider above to model how much of your generation you actually use during the day.

Estimates only. Real-world output depends on shading, panel tilt, season, and the electricity price you actually pay. The calculator assumes excess generation above your self-consumption is exported for free (plug-in solar cannot use the Smart Export Guarantee yet); update if a simplified SEG pathway opens.

Batteries: with or without solar

Batteries are interesting in the UK even without solar. With a time-of-use tariff like Octopus Flux you can charge cheaply overnight and either run your home from the battery during the peak window, or sell back to the grid at a much higher rate. Below are three worked examples - choose the one that matches your situation.

Track 1

Solar + battery

A small battery captures sunshine you would otherwise have exported for free, and lets you use it in the evening - shifting up to twice as much of your generation into useful self-consumption.

Energy through pack
400 kWh/yr
Saving per kWh
25.5 p
Payback
6.9 yr

Annual saving £102. Each kWh stored avoids paying 25.5 p/kWh from the grid in the evening (currently no SEG is paid for plug-in solar exports).

Worked example assumes Self-consumed instead of free export. Round-trip efficiency and battery degradation will reduce real-world figures by ~10-15%.

Track 2

Battery-only on Octopus Flux

No solar panels at all. Charge the battery from the grid at the cheapest 5-hour window (around 9 p/kWh), then either run the house off it during the 4-7 pm peak (avoiding 41 p/kWh import) or sell it back to Flux at the peak export rate.

Energy through pack
1,700 kWh/yr
Saving per kWh
7.0 p
Payback
21.0 yr

Annual saving £119. Half of each cycle assumed exported to grid at 29.3 p/kWh, half used in-home displacing 35.7 p/kWh peak imports - both bought at the 25.5 p/kWh off-peak rate.

Worked example assumes Avg of in-home displacement and Flux peak export. Round-trip efficiency and battery degradation will reduce real-world figures by ~10-15%.

Track 3

Battery-only off-peak charging

Simpler still: any time-of-use tariff with a cheap overnight rate. Charge the battery during off-peak, run the house from it during the day. No export needed - the saving comes from displacing daytime peak imports.

Energy through pack
1,700 kWh/yr
Saving per kWh
0.0 p
Payback

Annual saving £0. Each kWh is bought at the 25.5 p/kWh off-peak rate, then used in the day instead of paying the 25.5 p/kWh standard tariff.

Worked example assumes Daytime peak avoided. Round-trip efficiency and battery degradation will reduce real-world figures by ~10-15%.

Smart Export Guarantee: will you get paid?

The Smart Export Guarantee (SEG) is not currently available for DIY plug-in solar installations. SEG requires MCS certification for the generating equipment, which self-installed plug-in systems typically do not have. The government is exploring a simplified pathway for plug-in solar to access SEG, with a simplified Ofgem pathway expected around 2027. Until then, households with plug-in solar cannot receive payments for electricity exported to the grid via SEG.

Find your DNO

Within 28 days of installing your kit you must notify your Distribution Network Operator (DNO). The form is free, online, and takes a few minutes - no approval is required for sub-800 W plug-in solar. Enter your postcode below to find the right DNO.

Don't know your DNO? It's NOT the same as your electricity supplier - they own the cables, your supplier just bills you.

Landlord letter template

If you rent, the simplest path is to write to your landlord before installing. The template below references BS 7671 Amendment 4 (2026), explains that the kit is portable and reversible, and cites your right to request energy-efficiency improvements under the Renters' Rights Act 2025. Edit the bracketed sections, then send.

Preview the letterShow
Dear [LANDLORD NAME],

I am writing to let you know that I would like to install a small plug-in solar
system at [PROPERTY ADDRESS]. I wanted to share the details with you so that
you have everything you need on file.

What is plug-in solar?

A plug-in solar system is a small portable photovoltaic system - one or two
panels (around 800 W AC output) that plug into a standard three-pin socket. It
generates a small amount of electricity during daylight hours that the property
uses directly. It does not require any new wiring, sockets, or alterations to
the building.

Legal status

As of 15 April 2026, plug-in solar systems are recognised under BS 7671
Amendment 4 (the IET Wiring Regulations) and the G98 distribution code. The
government formally announced legalisation on 16 March 2026. The system I am
proposing falls under the 800 W AC output threshold and will be installed in
line with the manufacturer's instructions and the new wiring regulations.

What it means for the property

- No drilling, no fixings to the structure - the panel(s) will be mounted on a
  free-standing frame / on the balcony rail using clip-on brackets / on a
  removable wall hook. (Pick whichever applies.)
- The panels are easily removable at the end of the tenancy.
- The system plugs into an existing socket; no electrical alterations are made.
- The system has anti-islanding protection (it disconnects automatically in
  the event of a power cut), so there is no risk to anyone working on the
  property's electrics.
- I will notify our Distribution Network Operator within 28 days of install
  (G98 form) and inform my contents insurer.
- The system improves the energy performance of the property at no cost to
  you. This is consistent with the energy-efficiency improvements that tenants
  have a right to request under the Renters' Rights Act 2025.

I would be grateful if you could confirm in writing that you are happy for me
to proceed. I am happy to send you a copy of the manufacturer's compliance
documentation and the G98 notification on request.

Many thanks,

[YOUR NAME]
[DATE]

Latest UK plug-in solar news

13 MAY, 10:05
  • ·YouTube - Sunsave

    Plug-in solar panels | Are they worth it in the UK?

    The UK government announced in March 2026 that plug-in solar panels will be available to households 'within months', offering a genuine option for those unable to install rooftop solar. The British Standards Institution is expected to publish its new product standard for plug-in solar panels in July.

    Read at YouTube - Sunsave
  • ·Which?

    Plug-in solar panels to be made legal in UK homes - Which?

    Plug-in solar panels could be in shops 'within months' and help cut household energy bills, with retailers like Lidl and Amazon working with the government to bring them to the UK market.

    Read at Which?
  • ·IET

    IET & BSI officially publish Amendment 4 (2026) to BS 7671:2018 (IET Wiring Regulations)

    The Institution of Engineering and Technology (IET) and the British Standards Institution (BSI) officially released Amendment 4 (2026) to BS 7671:2018, the 18th Edition of the IET Wiring Regulations, introducing substantial changes for stationary secondary batteries and other areas.

    Read at IET
  • ·PV Magazine

    UK opens door to plug-in solar boom - PV Magazine

    Low-cost plug-in solar panels under 800 W will soon be legal in the UK, allowing installation without a qualified electrician and potentially boosting household solar adoption significantly.

    Read at PV Magazine
  • ·Carbon Brief

    Analysis: How 'plug-in solar' can save UK homes £1,100 on energy bills - Carbon Brief

    Plug-in solar panels could save a typical UK household £1,100 over their 15-year lifetime, providing around 400 kWh of electricity annually and potentially saving £110 on electricity bills each year.

    Read at Carbon Brief
  • ·GOV.UK - DESNZ

    Government to make 'plug-in solar' available within months - GOV.UK

    The government announced plans to make plug-in solar panels available in shops within months, working with retailers like Lidl and Iceland, and manufacturers such as EcoFlow, to bring them to the UK market.

    Read at GOV.UK - DESNZ

Frequently asked questions

Is plug-in solar legal in the UK in 2026?

Yes, in principle. The government announced legalisation on 16 March 2026 and BS 7671 Amendment 4 took effect on 15 April 2026, recognising small plug-connected PV sources. The full picture also depends on a separate BSI product standard expected in mid-2026 - until that publishes, kits sold as "compliant" are claiming compliance with a standard that is not yet finalised. The 800 W AC output limit applies, you must notify your Distribution Network Operator within 28 days (G98), and you should inform your home insurer.

Can renters install plug-in solar?

In most cases yes. Plug-in solar is portable and does not require permanent fixings to the building, which puts it outside the scope of most tenancy clauses on alterations. The Renters' Rights Act 2025 also gives tenants stronger rights to make energy-efficiency improvements, and we provide a downloadable letter template you can send your landlord. Always check your tenancy agreement and notify your landlord in writing before installing.

Will it void my home insurance?

Not if you tell your insurer. A non-compliant or undeclared electrical installation gives an insurer grounds to refuse a claim, but a sub-800 W plug-in solar system installed in line with BS 7671 Amendment 4 is now an accepted modification. Notify your insurer in writing - most will simply add a note to the policy at no extra cost.

Do I need an electrician?

No, not legally, for a sub-800 W kit. The whole point of the new framework is that plug-in solar can be installed without notifiable electrical work. That said, if your consumer unit is old (re-wireable fuses, no RCD), get an electrician to look at it before plugging anything in.

How much money will I save?

A typical 800 W kit in southern England generates roughly 500-700 kWh a year. At current unit rates (24-27 p/kWh), savings range from around £70 a year for an average household to up to £175 a year if you use most of the power during the day - giving a headline range of £70-£175/yr. Government modelling put the typical figure at £70-£110 a year with a roughly 4-year payback; households where someone is home during the day, or with always-on loads, often do better.

Can I get paid for excess solar I send to the grid?

Not yet, for plug-in solar. The Smart Export Guarantee currently requires MCS certification of the install, and DIY plug-in installs cannot be MCS-certified. Industry expects Ofgem to introduce a simplified SEG route for plug-in solar in 2027. Until then you only save on electricity you self-consume - which is fine, because self-consumed kWh are worth more than exported ones anyway.

Can I add a battery to a plug-in solar system?

Yes, and several kits now bundle one. A small (1-2 kWh) battery captures sunshine you would otherwise have exported for free, and lets you use it in the evening - shifting up to twice as much of your generation into useful self-consumption. With a time-of-use tariff like Octopus Flux a battery can also be charged from the grid overnight at low rates and discharged at peak: this works as a standalone strategy even without solar panels.

Do I need planning permission?

For panels mounted on a balcony rail, on a fence, in a garden, or on a wall in a non-conservation area, no - they are treated as portable equipment and fall under permitted development. For listed buildings, conservation areas, or panels mounted on the roof, check with your local authority.

Is plug-in solar different in Scotland, Wales or Northern Ireland?

Equipment rules and BS 7671 apply much the same across Great Britain, but Northern Ireland uses NIE Networks and has its own regulatory setup — use its published microgenerator / connection guidance instead of assuming a GB G98 form is always correct. Scotland shares GB distribution operators with England (for example SP Energy Networks). See the England, Scotland, Wales & Northern Ireland section on this page.

What is the 800 W limit and why?

The 800 W refers to the maximum AC output of the micro-inverter. It is set conservatively so the system cannot overload the ring main if everything else on that circuit is also drawing power. You can have panels totalling more than 800 W of nominal DC output, as long as the inverter is clipped to 800 W AC - which all UK-aimed kits are.

What if my house has a power cut - can plug-in solar keep things running?

No. The micro-inverter has anti-islanding protection (required by EN 50549) which shuts the system off the instant it detects a grid outage. This is to protect engineers working on the network. To run essentials during a power cut you need a separate off-grid battery system with a transfer switch, which plug-in solar kits don't provide.

Will it work in winter or on cloudy days?

Yes, but at reduced output. UK plug-in solar typically generates 70-90% of its annual yield between April and September. On a bright winter day you might still see 100-300 W; on a heavily overcast day in December, output can drop to 20-50 W. The annual figures already account for this seasonality.

What about non-compliant kits sold on Amazon and eBay?

Imported kits aimed at the German or Spanish market and sold on UK marketplaces may not meet UK standards. Common issues include inverters that are not certified to EN 50549 (so anti-islanding behaviour is unverified), missing earth bonding for panel frames, and plug types other than BS 1363. Look for an explicit statement of UK compliance with BS 7671 Amendment 4 and, once published, the BSI product standard. Avoid generic listings without a UK importer.

Glossary

Plug-in solar
A small PV system - typically one or two panels and a micro-inverter - that connects to the home via a standard three-pin plug rather than a hard-wired spur. Also called balcony solar, DIY solar, or Balkonkraftwerk.
Micro-inverter
A small inverter, typically clipped to the back of a single panel, that converts the panel's DC output into 230 V AC. UK-aimed micro-inverters are clipped to 800 W AC output.
Anti-islanding
A safety feature, required by the EN 50549 standard, that automatically shuts the inverter off within ~200 ms if it detects the grid has gone down. Protects engineers working on the network during a fault.
BS 7671
The IET Wiring Regulations - the standard that all UK electrical installation work must follow. Amendment 4, effective 15 April 2026, updates Chapter 712 to permit small plug-connected PV.
G98
The Distribution Network Operator notification standard for generators under 16 A per phase. Plug-in solar must be notified to the local DNO within 28 days of install. Free online form, no approval required.
DNO
Distribution Network Operator - the company that owns and runs the lower-voltage cables that bring electricity to your home. There are six DNO regions in Great Britain. Different from your electricity supplier.
MCS
Microgeneration Certification Scheme - the consumer-facing certification scheme for renewables installs. Currently a gateway to the Smart Export Guarantee. Plug-in DIY installs are not MCS-certifiable.
SEG
Smart Export Guarantee - the framework that pays households for electricity they export to the grid. Currently requires MCS certification. A simplified pathway for plug-in solar is expected ~2027.
kWh
Kilowatt-hour - the unit your electricity bill is measured in. A typical UK home uses about 2,700 kWh a year. An 800 W plug-in solar system in southern England generates about 500-700 kWh a year.
Self-consumption
The share of your solar generation that is used inside the home rather than exported. Self-consumed kWh save you the import unit rate (around 25 p), while exported kWh earn the export rate (around 12-15 p), so self-consumption is worth roughly twice as much.
Time-of-use tariff
An electricity tariff with different rates at different times of day. Octopus Flux, for example, charges peak (4-7 pm) and pays a high export rate during the same window, with cheap import rates overnight - which makes a battery valuable even without solar panels.

Primary UK sources

We research this page directly from the UK government and the electrical regulators every day, rather than from secondary press coverage. The links below are the same primary sources our daily Gemini brief grounds against — go straight to them if you want the original wording.

We have no commercial or political relationship with any of these bodies. They are listed because they are the authoritative public sources for UK plug-in solar policy and safety.

Today's grounding citations

The additional pages Gemini's Google Search grounding consulted for today's refresh. Official UK sources are listed first; trade press and other secondary sources follow.

Editorial independence

4 Billion Years On is impartial. We are not a manufacturer, retailer or installer. The products listed above are chosen for editorial reasons - because they are relevant to the UK market right now - not because anyone has paid us to feature them.

Only links to the Amazon site from the products table (specific product pages with a /dp/ or /gp/product/ URL) use our Amazon Associates account — the same programme as our energy, climate and AI book pages. For UK, Ireland and US visitors those Amazon URLs include our affiliate tag; if you buy after clicking, we may earn a small commission at no extra cost to you. Links to manufacturer sites (for example EcoFlow), other retailers or anywhere that is not Amazon are ordinary outbound links — we do not earn commission from them here. The choice of which products appear, and what we say about them, is never influenced by affiliate availability. Pages, paragraphs and rankings are not for sale.

Have a correction or want to suggest a kit we have missed? Email us at chris.4billionyears@gmail.com.