Balcony solar: how much it really produces and what is allowed
Yield by orientation and mounting, shading, the 800 W rule and registration in the UK, Germany, Austria, Switzerland, France and Belgium.
Vertical on the railing costs about a third
Fraunhofer ISE puts the loss of a vertical south facing panel at about 29 percent compared with the best tilt. In winter the vertical panel can even win, because it faces the low sun head on. East and west balconies produce roughly 30 percent less than south.
Shade matters more than you think
In a Stiftung Warentest test of eight systems, a quarter of the panel in shade left even the best system with little more than half its output. A plant pot or a balcony divider can cost more than a poor orientation.
The 800 W rule and registration
Most countries now allow plug-in systems with an inverter of up to 800 W, and an EU recommendation of April 2026 asks all member states to remove obstacles. Switzerland still limits them to 600 W. How you register differs a lot: a register in Germany, the grid operator in Austria, Switzerland and the UK, the Enedis agreement in France and regional rules in Belgium.