My customer's new system in Germany will get a smart meter soon. Someone told him he then gets nothing for the power he exports when exchange prices are negative. Is that true, and from when?

Plain explanation

Since the 'Solarspitzengesetz' took effect on 25 Feb 2025, EEG §51 (1) says that for periods when the spot market price is negative, the payment value drops to zero. For systems under 100 kW, §51 (2) delays this until after the end of the calendar year in which the system gets an intelligent metering system (iMSys): a smart meter fitted in 2026 means unpaid negative-price periods from 1 Jan 2027. Systems under 2 kW are exempt until the Bundesnetzagentur sets its rules. The power is still taken by the grid, it is just not paid in those periods. To soften this, §51a extends the payment period after the normal 20 years; for solar the number of zero-paid quarter-hours is multiplied by 0.5 and converted into extra 'full-load quarter-hours'. Systems commissioned 1 Jan 2023 to 24 Feb 2025 keep the older rules. This is separate from the 60 % feed-in cap (§9), which ends only once an iMSys plus a control box are installed and tested. In practice, the best answer for the customer is more self-consumption at midday: battery charging, hot water, EV charging. Not legal advice: the grid operator's billing applies the exact rules.

Steps from the source

1. Check the commissioning date: from 25 Feb 2025 the new §51 applies; 1 Jan 2023 to 24 Feb 2025 keeps the old rules
2. Note the year the iMSys is installed: unpaid negative-price quarter-hours start on 1 January of the following year (systems under 100 kW)
3. Plan midday self-consumption (battery, heat pump hot water, wallbox) so less power is exported in those periods
4. Tell the customer the lost time is partly made up after year 20 (§51a, factor 0.5 for solar)
5. Keep it apart from the 60 % feed-in cap (§9 EEG), which has its own end condition

"Für Zeiträume, in denen der Spotmarktpreis negativ ist, verringert sich der anzulegende Wert auf null."

Word for word from the source.

Source

Where installers ask this

• 60 % statt Smartmeter (r/DeutschePhotovoltaik)
• photovoltaikforum.com/core/article/201-solarspitzengesetz-der-verg%C3%BCtungsanspruch-bei-negativen-strompreisen/

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.