"If the strong expansion of photovoltaics continues and demand does not pick up, there will foreseeably be more hours with negative prices on the electricity exchange," says Fabian Huneke, project manager for the energy transition in the electricity sector at the Berlin think tank Agora Energiewende.

For example, there is a clear need to accelerate the decarbonisation of the industrial, building and transport demand sectors, while at the same time the expansion of photovoltaics is now slightly above target with 101 GW of installed capacity in Germany.

In any case, the high simultaneity of solar power generation - especially at midday - contributed to prices on the spot market falling into negative territory for more than 400 hours last year.

That adds up to quite a lot

Over the course of the year, the number of negative hourly prices totalled 459 at an average price of -5.18 EUR/MWh, according to Montel data. In the previous year, there were 301 hours and an average price of -7.54 EUR/MWh, according to BNetzA data.

The occurrence of negative price hours could fall again through the rapid electrification of industry, buildings and transport, says Huneke. "It must also be technically possible to limit the feed-in of smaller PV systems so that controllable systems are created in the future," says the Agora expert.

Solar peak law

In order to "meet the challenges of temporary surpluses in electricity generation", the remaining "traffic light" parties, the SPD and the Greens, presented a bill to amend the Energy Industry Act (ENWG) in the last week of the Bundestag session before the elections.

This so-called Solar Peaks Act was passed by the parties together with the CDU/CSU parliamentary group. It contains regulations intended to increase flexibility in the electricity system and also affects direct marketing and regulations on remuneration in times of negative prices through adjustments to the Renewable Energy Sources Act (EEG).

Among other things, the amendments to the Renewable Energy Sources Act (EEG) mean that new plants will no longer be subsidised during periods of negative exchange electricity prices. To compensate for this, these hours are to be added to the subsidy period after the end of the 20-year EEG subsidy period.

How things will continue this year

In terms of price, however, solar peaks with surplus electricity will continue to make themselves felt on the market this year. Fabian Zuber, Managing Director of the Reiner Lemoine Foundation, comments: "Negative prices will continue to emerge this year. But if the BNetzA and the distribution system operators remove the barriers to storage and flexibility, negative prices could disappear very quickly."

The previous German government had actually assumed in its forecasts that German electricity consumption would rise to 750 TWh by 2030 due to the electrification of industrial processes, the expansion of heat pumps and an increasing number of electric cars. It based its expansion path for renewables on this in order to be able to cover 80% of this.

However, following the energy price crisis in 2022 as a result of the Russian war of aggression against Ukraine and weak economic development since then, electricity consumption in 2024 was only around 512 TWh.