Balcony solar: First balcony power plant draft for VDE product standard is available

Given high electricity prices, balcony power plants are enjoying increasing popularity – around 200,000 units are already installed in Germany. So far, the available plug-in solar devices, consisting of a solar module, inverter, and connection cable, are not certified. The DKE (German Commission for Electrical, Electronic & Information Technologies) has been driving development since 2017 and, with its draft product standard, aims to ensure safe operation for users.

While initially referred to as guerrilla photovoltaic systems, the market for plug-in solar devices is now developing dynamically. According to a study by HTW Berlin, a total of 128,000 plug-in solar devices were added in 2020 and 2021, generating a total output of up to 51 megawatts. Now, the DKE (German Commission for Electrical, Electronic & Information Technologies) has presented its first draft of a VDE (Association for Electrical, Electronic & Information Technologies) product standard, which is now open for comment. While the study indicates that 70 percent of the installed devices use the Schuko plug common in household appliances, the DKE already pointed out in its 2018 installation standard for plug-in solar devices that these mini-PV systems are not household appliances.

Since electricity is not only received but also fed into the grid, the DKE (German Commission for Electrical, Electronic & Information Technologies) recommends a special energy socket or comparable solutions. This ensures the electrical safety of the building's electrical installation and prevents users from touching the metal plug pins, thus protecting them from electric shock. The more devices are on the market, the higher the risk of damage can be – which is why a product standard covering all safety aspects is urgently needed.

The aim of the product standard
is to address the two options for installing a plug-in solar device: direct wiring, which must be carried out by a qualified electrician, or connection by the user via a power outlet. The draft of the new product standard revisits the topic of plugs and explains that there are various ways to ensure a safe connection. Furthermore, an informative appendix deals with the commonly used Schuko plug, which is currently neither permitted nor prohibited, in order to provide expert guidance and resolve this gray area during the comment phase.

The aim is to comprehensively describe the technical safety requirements so that manufacturers and suppliers of such devices, who purchase individual components and market them as plug-in solar systems, can work with them. The standard also explains what needs to be considered regarding the electrical safety of the building installation. It covers both models that are fully assembled and can be installed directly, as well as the wide variety of products consisting of one or two modules, an inverter, and several cables.

In addition to safety requirements, testing criteria are described according to which devices can be tested to demonstrate electrical safety via a declaration of conformity. This provides end customers with transparent proof of the technical safety and quality of the purchased product. Finally, a summary is provided outlining what must be considered during registration and installation, and what information must be made available to the end customer through documentation.

Comment Phase and Next Steps:
Due to the high relevance of the topic, the DKE is actively drawing attention to the start of the comment phase. The debate surrounding the so-called "energy transition for everyone" is sometimes very intense, and the DKE hopes for a factual discussion. "We have a current topic that is important for the personal energy transition of citizens. We want to shape and advance this safely, with the greatest possible transparency in the standardization process. Therefore, we hope for active public participation," states Alexander Nollau, Head of the Energy Department at the DKE. The DKE also has a strong interest in accelerating the process.

Following the comment phase, in which all citizens can participate, all comments will be reviewed, and depending on the circumstances, a mediation process may follow. The current target date for the final product standard is the end of 2023 – provided there are no unforeseen delays. "And we can reassure you: Devices already on the market by then will not be affected by the product standard and can continue to be used," said Nollau.

Press release 14.10.2022