Knowledge

Guides

Background on technology, regulation and economics — written for people who want the detail.

Registering balcony solar in Germany: what is actually required in 2026

Since the first solar package, registering a plug-in solar device takes minutes. What remains, what was dropped — and which deadlines apply.

6 min · Reading timeUpdated 14 June 2026

One registration only: the market master data register, within a month of commissioning.
Registration with the grid operator has been abolished entirely.
Up to 800 W of inverter output and 2,000 Wp of module power are permitted.

7 min

South delivers the highest annual yield. For your electricity bill that is often the wrong thing to optimise — here is why.

8 min

A battery reliably raises self-sufficiency. Whether it also pays comes down to one number — the cost per stored kilowatt hour.

9 min

The question is never "old building or not" but always: what flow temperature does the building need on the coldest day?

6 min

Every self-consumed kilowatt hour is worth four times an exported one. These are the measures that actually move the number.

5 min

Procurement, grid fees, taxes, levies: only a third of the price is negotiable at all. That explains why switching supplier delivers less than hoped.