PV-Direktvermarktung: Transitioning Small Rooftop Installations to the Market Without Losses
The proposed reform of the Renewable Energy Act (EEG) could significantly hinder the growth of private photovoltaic (PV) installations in Germany. According to an analysis by Agora Energiewende, based on calculations from the Fraunhofer Institute for Solar Energy Systems (ISE), the German government’s draft legislation aims to abolish the fixed feed-in tariff for small rooftop systems up to 25 kilowatts peak. This change may present considerable challenges for households with rooftop solar systems, especially in terms of economic viability.
Market Integration Challenges
Instead of benefiting from a guaranteed feed-in tariff, households are expected to sell excess solar power directly to the market or cease feeding into the grid. While this may sound like a step toward market integration, the reality presents significant bureaucratic and financial obstacles. Small rooftop PV systems with about 38 gigawatts peak of installed capacity currently account for nearly one-third of Germany’s solar electricity. The fixed feed-in tariff has provided reliable and predictable returns on investments. Without it, many homeowners might find it economically unfeasible to operate their solar systems.
Hidden Costs of Direct Marketing
Research indicates that a four-person household would need to sell power through currently available, unfunded direct marketing models. This scenario could impose additional annual costs ranging from €185 to €277 compared to the existing system, largely due to service fees and transaction costs from marketers, which currently stand at approximately €140 per year, plus installation fees.
For households with low self-consumption, the financial incentive of solar installations decreases significantly. Many lower-income households may lack the budget to invest in renewable technologies, making them less likely to transition to solar energy solutions.
Implications of Zero Feed-in
Opting for zero feed-in could impose an even heavier annual burden, increasing costs for existing households by €281 to €333. Economically and environmentally, this is the least advantageous option as valuable solar energy that could mitigate midday market prices would be wasted, raising electricity costs for all as near-consumption generation becomes artificially limited.
Transition Phases and Digital Infrastructure
Agora Energiewende advocates for a more gradual transition, arguing that the proposed two-year period is far too short to establish the needed digital infrastructure. A postponement of mandatory direct marketing until 2031 would allow time for creating a streamlined market entry for small producers. Experts propose developing standardized digital interfaces, automating market communication, and accelerating the rollout of smart meters. Such measures would facilitate genuine competition among marketers and aggregators, reducing annual marketing costs for small systems.
Economic Impact of Extended Feed-in Tariffs
Extending the fixed feed-in tariff would incur minimal extra costs for the state’s EEG account, only around €160 million in additional funding for new installations by 2030. Given the current solar funding expenditures of approximately €8 billion, this is a relatively minor expense. Furthermore, costs associated with the EEG account are expected to decline after the next decade as expensive older systems from the solar boom around 2010 gradually exit the twenty-year subsidy scheme.
Should direct marketing still fail to meet economic thresholds by 2031, the think tank suggests provisions requiring grid operators to market combined electricity from private small installations at current market prices, passing the revenue to consumers after deducting processing fees.
Fair Grid Costs and Social Inclusion
Research warns against overwhelming system operators due to concurrent discussions on grid cost reforms. While greater participation in grid costs is fair, especially as solar system owners continue to rely on the grid as a backup, the proposed fixed fee should not exceed €100 per year. Anything above this could jeopardize the economic viability of private solar systems and stall further development.
The study concludes that the energy transition within private homes can remain a successful model if considered holistically. By combining solar systems, storage, heat pumps, and electric vehicles, homeowners can reduce total energy costs significantly compared to fossil fuels, safeguarding themselves against future price shocks in raw material markets. To ensure this cost advantage is not exclusive to affluent households, governmental support mechanisms for lower-income families—such as social leasing models for electric vehicles and heat pumps—are essential for fostering social participation in the energy transition.
