The DIN VDE standard defines plug-in solar devices as complete products and establishes power limits based on plug type and safety requirements
Wider plug options, clearer safety rules, and formal testing guidance aim to support manufacturers, testers, and end users
This standard is expected to inform future international guidelines as global interest in safe, small-scale PV systems expands
Germany is set to publish the world’s 1st product standard for plug-in solar devices in December 2025, marking a major milestone for this fast-growing PV segment. The new standard formally defines plug-in solar devices – also known as balcony power plants and guerrilla PV – as complete products for the first time.
Developed by the German Commission for Electrical, Electronic & Information Technologies (DKE) after 8 years of technical work and consultations, and 2 draft versions later, the standard will be published as DIN VDE V 0126-95 VDE V 0126-95:2025-12 "Plug-in solar devices for grid-connected operation - Part 95: Safety requirements and tests.
The new rules set limits on how much power a plug-in solar system is allowed to produce. All systems can only feed up to 800 VA of power into the home grid due to safety rules. If the system uses a regular household plug, the total solar panel capacity is approved at 800 W and must stay below 960 W. If it uses a special safety plug designed for higher loads, the system can be much larger, up to 2,000 W. These limits are meant to keep household wiring safe while still giving people options for bigger plug-in solar setups.
It allows plug-in solar devices to be connected using more types of plugs, including normal household sockets, as long as safety measures are built in. These protections can include safer plug designs or an internal circuit breaker. This basic protection can also be achieved via galvanic isolation in the inverter. The special energy plug used earlier is still allowed, but no longer required.
The standard is aimed at clarifying technical requirements for manufacturers and suppliers of these products. Testing facilities will be able to use this standard to test the safety of such devices, while end users will have comprehensive and clear information for their safe operation, said VDE Association for Electrical, Electronic & Information Technologies CEO Ansgar Hinz.
A standard interpretation and FAQs will be provided in December to assist with the application of the product standard, it added.
“The aim was to reconcile the safety of plug-in solar devices, in particular the risk of electric shock, mechanical safety, and overloading of domestic installations with consumer interests,” explained VDE.
Many countries and the international solar standards committee are interested in Germany’s new product standard, says the VDE. Since grid rules vary by country, only the non-grid parts can be used globally.
“It therefore makes sense to transfer the part of the standard that does not deal with grid requirements to international standardization,” opines Head of the Energy Department at German Commission for Electrical, Electronic & Information Technologies, Alexander Nollau. “This part is certainly useful and relevant for all countries. The product standard will therefore most likely serve as the basis for the development of an international standard.”
The new standard does not, however, cover plug-in solar devices with energy storage. Work on developing such a standard is already underway.
In Germany, around 1.15 million plug-in solar devices with a cumulative output of around 1.14 GW are registered with the Federal Network Agency (Bundesnetzagentur), according to the German solar association BSW-Solar, which has welcomed the new standard.
BSW-Solar CEO Carsten Körnig said, “The DIN standard for plug-in solar devices ensures legal certainty for manufacturers, retailers and end users and strengthens a market segment that has been growing strongly for several years. Plug-in solar devices are a great way for millions of tenants and apartment owners in multi-family buildings to actively participate in the energy transition.”
In 2024, Bundesnetzagentur revised registration rules for balcony solar systems to reduce bureaucracy and boost their adoption (see Germany Simplifies Rules For Balcony Solar Power Plants).