More than one million solar panels have been installed in Germany over the past three years. What is new is that they increasingly have built-in batteries to store energy.
The units can measure up to two square meters and fit up to four in a small system. Installation is simple, and the systems work as reliably as other devices, only in reverse: electricity flows from the solar module through an inverter and a socket into the home’s electrical grid.
Cheap electricity from your own balcony
Solar panel and battery storage prices have dramatically fallen by half worldwide in just two years. Small models cost around 200 euros, and larger models, with four panels and storage, cost less than 1,000 euros. In Germany, the price of electricity generation ranges between 7 and 15 cents per kilowatt-hour. It is much cheaper than mains electricity, which costs about 40 cents on average.
According to the Berlin University of Applied Sciences and Economics (HTW), an investment usually pays for itself within four to seven years. After that, the self-generated electricity becomes free. Additionally, HTW has a calculator that determines which system is appropriate for each home.
While solar panels can last more than 30 years, batteries “have a useful life of 10 to 15 years,” says Volker Kuachning, professor of renewable energy systems at HTW. With four units and storage, it is possible to cover almost half of the electrical needs of a two-person household in Central Europe.
More sun, more electricity
“Compared to the rest of the world, the majority of plug-in solar devices are sold in Germany,” says David Breuer, CEO of Cologne-based online store Yuma.
This prosperity is due to several reasons: lower prices, improved technology, and political support. Since 2023, private solar energy systems in Germany have been exempt from VAT. In June 2024, the European Union adopted guidelines for electrically powered solar devices. As of October 2024, renters and homeowners in Germany can install solar panels on their balconies easily, without bureaucracy or electricians.
In Germany, appliances with a power of up to 2000 watts are allowed. In most EU countries, the devices can supply up to 800 watts of electricity directly to the power grid. This prevents overloads in the home’s electrical wiring.
“We developed the model in Germany and now we see great interest in other countries as well,” Thomas Seltmann, an expert in solar energy devices at the German Solar Energy Association, told DW. “We recently visited a delegation from Tokyo. They wanted to present solar devices and were asking about their technical safety.”
Participation in the energy transition
Germany aims to be climate neutral by 2045. Plug-in solar devices could cover up to 2% of the country’s electricity needs by then, estimates energy expert Professor Claudia Kimfert from the German Institute for Economic Research (DIW). Currently, the majority of solar energy in Germany comes from rooftop installations, followed by large solar collectors.
“Pluggable solar devices allow people to participate in the energy transition, reduce electricity costs, and become more independent from fluctuations in energy prices.”
Good advice is essential
Another important aspect is that “having good information is crucial before purchasing solar energy systems,” according to Tobias Otto from the German Society for the Promotion of Solar Energy (SFV), which provides independent advice in the field of solar energy.
For example, some battery-powered plug-ins have an emergency power supply in case of a power outage. Many batteries can also be installed outside. However, they will consume some electricity in very cold or warm temperatures.
The quality of the products is also important. Seltman, who worked at a consumer service center, said experts advise against shopping at low-cost and discount stores because they “carry a lot of weird products.” “We therefore recommend purchasing from specialized stores.”
(RMR/EL)