Balcony solar (plug-in solar): solar power for tenants and owners

In short: A balcony power plant (plug-in solar device) is a small solar system with one to four modules and a micro-inverter that you set up yourself and feed into a socket. The power first covers consumption in your own household.

In more detail: Since the Solar Package I (2024) devices with up to 800 volt-amperes of inverter output may be operated, with up to 2000 watts of module power. Registration is simplified.

In Depth

• Structure: Solar modules, micro-inverter (converts DC to AC), connection cable. Optionally a battery.
• Yield: Depending on orientation, shading and location roughly 400 to 800 kWh a year with two modules. South, 30 to 40° tilt and no shade are ideal, east-west works well too.
• Economics: Every self-used kilowatt-hour saves the electricity price. Surplus without a meter flows into the grid, usually without being paid for. Payback often after a few years. Use baseload (fridge, router, standby) best in the daytime.
• Registering: Register in the Federal Network Agency’s Marktstammdatenregister. Under the new rules a notification to the grid operator is no longer required, but can still raise questions depending on region and tariff.
• Meter: Old meters with a backstop are required. A meter that runs backwards is tolerated for a transitional period until the grid operator replaces it.
• Plug: A Schuko plug is now tolerated. Safer is a dedicated feed-in socket meeting the standards. Buy a certified device (VDE standard).
• Tenants and owners’ associations: The right to consent to balcony power plants has been strengthened. Mounting (fall protection, wind) remains the installer’s responsibility. Inform the landlord or owners’ association beforehand.
• Tax: For small systems VAT on the purchase is waived, income is exempt from income tax. Rules can change, check current guidance.

See also: photovoltaics basics, kilowatt-hour