I want my mostly self-built system in Germany commissioned this year to lock in the current feed-in tariff. What legally counts as 'commissioning' under the EEG, and does the meter have to be in?

Plain explanation

EEG §3 Nr. 30 defines commissioning ('Inbetriebnahme') as the first time the system is put into operation after it is technically ready. Technically ready means the modules are fixed at their permanent place and permanently installed with the accessories needed to produce AC power (so the inverter is connected). Swapping parts later does not move the commissioning date. The law text does not tie the date to the feed-in meter being installed. Separately, the system has to be registered in the Marktstammdatenregister within one month of commissioning (MaStRV §5). In practice the grid connection request (Netzanschlussbegehren) and a licensed electrician for the grid connection are still needed. Start them early because grid operators can be slow at year end. Not legal advice: what changes for new systems after 2026 had not been confirmed in the sources we checked, so plan with your grid operator, not with forum rumours.

Steps from the source

1. File the grid connection request with the grid operator now
2. Mount the modules at their final place and permanently wire inverter and AC accessories: that is the 'technical readiness' test
3. Have a registered electrician do the grid-side connection and sign the commissioning record (Inbetriebsetzungsprotokoll) with the date
4. Register the system in the Marktstammdatenregister within one month of commissioning

"„Inbetriebnahme“ die erstmalige Inbetriebsetzung der Anlage ausschließlich mit erneuerbaren Energien oder Grubengas nach Herstellung der technischen Betriebsbereitschaft der Anlage; die technische Betriebsbereitschaft setzt voraus, dass die Anlage fest an dem für den dauerhaften Betrieb vorgesehenen Ort und dauerhaft mit dem für die Erzeugung von Wechselstrom erforderlichen Zubehör installiert wurde"

Word for word from the source.

Source

Where installers ask this

• Der Weg zur Einspeisevergütung mit Inbetriebnahme in 2026 - Realistisch? (r/DeutschePhotovoltaik)
• photovoltaikforum.com/thread/265543-10-15kwp-anlage-jetzt-noch-schnell-mit-esv-oder-was-kommt-ab-2027/

General guidance based on the manufacturer's manual or the named source. Always follow the current manual for your exact model and your national code. DC and AC electrical work is for qualified installers only. Not affiliated with or endorsed by any brand named; trademarks belong to their owners.