Balcony power plants: small modules for a major energy transition

The success of a technology often depends not on how advanced or efficient it is, but on how accessible it is to the masses. Things that are expensive, bulky and complicated are reserved for the few. For a long time, this also applied to photovoltaic systems, which require large roofs. But balcony power plants are changing this.

"It really is plug and play." Pierre (name changed by the editors) points to a microwave-sized battery with a built-in inverter on the balcony that he recently installed. On one side, it is connected via cables to four solar modules measuring around one square metre, which are attached to the balcony's privacy walls. On the other, a thicker cable runs via a water-resistant plug directly into a socket. The balcony power station can feed up to 799 watts of electricity into the grid of the flat in the apartment block. From there, it finds its own way: on sunny days, fridges, lamps, and routers run independently. Registration with the local authority or grid operator is not necessary for the small systems.

According to Oekotopten, around a quarter of the annual electricity consumption of a two-person household – around 200 euros – can be saved with a balcony power plant. No licences required, ordered online for around 700 euros and assembled by yourself. It should pay for itself after around four to six years. With a lifespan of around 25 years, that leaves around 20 years of free electricity. Only the battery will probably need to be replaced, depending on the storage conditions.