Last reviewed: 5 September 2026. UK requirements are from SI 2026/848 and the DESNZ Interim Product Specification version 2.0 (July 2026). The German material is included as context and comparison, not as advice on German law — if you live in Germany, take German advice.
Germany has had legal, mass-market balcony solar for roughly a decade, and it spent most of that decade arguing about the same five things Britain is about to argue about. Power limits that were set too low and had to be raised. Landlords and flat-owner committees saying no. A registration process that nobody could complete. A socket standard that split the industry. And an argument about whether the meter runs backwards. Germany resolved four of those by changing the law and one by changing the meters. Britain has copied some of the answers, ignored others, and in two places has taken a deliberately different route. This page sets out which is which.
What Britain has already copied
The resemblance is not accidental. The UK’s Interim Product Specification is explicitly derived from the German technical work — the German pre-standard DIN VDE V 0126-95 on plug-connected PV — and the family resemblance shows in the numbers.
| Question | Germany | United Kingdom |
|---|---|---|
| Maximum AC output | 800 W at the connection point (raised from 600 W in May 2024) | 800 W, and no more than 3.5 A (spec clause 4.1); 800 W is written into SI 2026/848 itself |
| Maximum DC panel capacity | Commonly 2,000 Wp | 2,000 W of panels, and no more than 4 modules with a maximum of 2 in series |
| Plug type | Schuko domestic plug or Wieland connector; the argument over which took years | BS 1363-1 non-rewireable plug with a BS 1362 fuse of 5 A or less (clause 6.2.3.2). No alternative permitted |
| Registration | Marktstammdatenregister entry required; separate notification to the network operator abolished in 2024 | Notify your DNO under G98 within 28 days of commissioning. No consumer register |
| Product registration | Conformity through product standards | The device must be on the ENA Type Test Register before it is placed on the market (clause 7) |
| Battery in the kit | Permitted; storage-equipped balcony kits are a large and growing product category | Not permitted. SI 2026/848 prohibits a plug-in microgenerator importing electricity in order to store it |
| Devices per home | Effectively governed by the 800 W ceiling | One device per property under G98, even though the specification would allow one per final circuit |
Lesson one: the power limit will be argued about again
Germany set its ceiling at 600 W, discovered that panel sizes had outgrown it, and raised it to 800 W in the Solarpaket I package in May 2024. Britain has started at 800 W — but has started there in 2026, when a single modern panel is routinely 430–500 W and a pair comfortably exceeds the inverter’s ceiling on a bright afternoon.
This is not a flaw so much as a design choice: the inverter is meant to be the bottleneck, and over-panelling is how you flatten the output curve and get more useful hours out of a dull morning. We cover the arithmetic in how many panels sit behind an 800 W inverter. But the German experience suggests the ceiling is a political number as much as a technical one, and that it moves. If you are budgeting on the assumption that today’s limit is permanent, budget for the possibility that it is not.
One asymmetry worth noticing: in the UK, 800 W is in the statutory instrument, not just in a specification. Changing it means changing legislation, which is slower than revising a guidance document.
Lesson two: the landlord and the committee problem gets solved by law, or not at all
This is the single most useful thing Britain could take from Germany, and so far has not.
German tenants and flat owners spent years being refused by landlords and by owners’ associations on aesthetic grounds, and the refusals were usually lawful. That changed in October 2024, when plug-in solar devices were added to the list of “privileged” structural alterations under the German Wohnungseigentumsgesetz — the flat-ownership statute — meaning an owner has a right in principle to have the installation approved, with the community able to argue about how rather than whether. Parallel changes were made for tenants in the Civil Code.
Britain has no equivalent. A tenancy agreement that bars alterations still bars a balcony kit; a lease that reserves the external structure to the freeholder still reserves it. There is no statutory right to install, no deemed consent, and no appeal route beyond ordinary landlord-and-tenant law. See plug-in solar for renters and plug-in solar in a leasehold flat for what that means in practice.
[VERIFICAR: whether DESNZ or MHCLG has committed to reviewing tenancy and leasehold consent for plug-in solar. We have found no such commitment in the July 2026 government response, but a later ministerial statement would change this section.]
Lesson three: a register only works if it is one register
Germany originally required both an entry in the national Marktstammdatenregister and a separate notification to the local network operator. The duplication produced exactly what you would expect — a large population of unregistered kits — and the second step was abolished in 2024.
Britain’s arrangement is different in kind. There is no consumer-facing register of who owns a kit. What there is instead is a product register: the ENA Type Test Register, which the device must appear on before it can lawfully be sold, and a one-off notification you make to your distribution network operator under G98 within 28 days of switching the kit on. That is a fit-and-inform process, not an application: you are telling them, not asking. See how to fill in a G98 notification.
The German lesson still applies, though, in a form Britain has half-learned. The burden that gets ignored is the one that feels pointless to the person carrying it. The G98 notification feels pointless — which is why telling your DNO you have removed a kit is going to be ignored almost universally unless someone makes it easy.
Lesson four: the plug argument is over before it started here
Germany’s long-running dispute was between the ordinary Schuko domestic plug and the Wieland special connector, with electricians’ bodies favouring Wieland and consumers overwhelmingly buying Schuko. It was eventually settled in favour of the domestic plug, with the technical safety burden pushed into the inverter.
Britain has skipped the argument by writing the answer into the specification: a non-rewireable BS 1363-1 plug, fused at 5 A or less, and a requirement that the voltage at the pins falls below 34 V within 100 ms of the plug being pulled. That is a stricter position than Germany reached, and it is the reason a German kit cannot simply be re-plugged for UK use — the safety behaviour is a property of the inverter, not the plug. See importing a balcony solar kit from the EU.
Lesson five: the meter question is where the two countries genuinely diverge
The early German scare story was the meter running backwards — old Ferraris-type disc meters physically reversing when a balcony kit exported, which network operators treated as a serious problem. The 2024 reforms took a pragmatic line: install and let the operator swap the meter in due course.
Britain does not have that problem, because Britain has spent a decade fitting smart meters that simply do not run backwards. What it has instead is a different disappointment: a self-installed kit does not qualify for the Smart Export Guarantee, because the SEG requires MCS certification or an accepted equivalent and an export MPAN. So exported units are given away. See plug-in solar and your smart meter and does plug-in solar export to the grid.
The practical consequence is that the entire economic case in Britain is self-consumption, and the whole skill is using more of your own generation. Our savings calculator is built on that assumption.
The one place Britain has gone the other way on purpose
Storage. German balcony kits with integrated batteries are a mainstream category; the UK’s SI 2026/848 explicitly prohibits a plug-in microgenerator from importing electricity in order to store it, which rules the whole product class out. We think this is the most consequential single difference between the two markets, because storage is what turns a 4 pm surplus into a 7 pm saving.
It does not stop you having a battery — it stops the battery being part of the plug-in device. A separately installed home battery is a different legal object with a different route. See can I add a battery to plug-in solar and a home battery without solar panels.
What we would watch next
- The one-device rule. The specification contemplates one device per final circuit; G98 currently allows one per property. That gap is the most likely thing to move first — see can I have two plug-in solar kits.
- Consent rights for renters and leaseholders. Germany needed primary legislation. Britain has none in prospect.
- The battery prohibition. Written into the statutory instrument, so it needs an amending SI to change.
- Northern Ireland. Regulation 3 of SI 2026/848 reaches England, Wales and Scotland only. See plug-in solar in Northern Ireland.
Primary sources.
SI 2026/848 (legislation.gov.uk) ·
DESNZ, Plug-in Solar Device Interim Product Specification v2.0 (PDF) ·
DESNZ plug-in solar consultation and government response ·
Ofgem, Smart Export Guarantee ·
Energy Networks Association, find my network operator.
German law is described here for comparison only and we do not advise on it. See our editorial methodology.