PV+BESS and the Market Premium
How market premium mechanisms shape the economics of green battery hybrids, and why negative prices are no longer an exception.
In 2025, Germany experienced 576 hours with negative day-ahead electricity prices. Negative pricing is no longer a rare market event. It has become an increasingly important factor for renewable energy projects and their revenue structures. For solar assets in particular, this raises an important question: How much generation is actually affected by §51 EEG, and what role can green energy storage play in mitigating its impact?
A Growing Share of Generation Is Affected
The increase in negative price periods directly affects the share of renewable generation that no longer qualifies for market premium payments under §51 EEG. Our analysis shows that even under the current 6-hour rule, a significant share of annual solar generation can fall within §51 periods. Under shorter threshold assumptions, the affected share becomes even more substantial.
What Does This Mean for Solar Projects?
Using a representative 10 MW solar project as an example, we analysed how much annual generation occurs during periods affected by §51 EEG. The results are striking: • More than 25% of annual generation can be affected under a 1-hour rule. • Even under a 6-hour rule, approximately 17% of annual generation remains exposed. For project owners, this means that an increasing share of renewable generation may be produced without market premium support.
How Much Market Premium Can Green Energy Storage Recover?
Battery storage can help shift renewable generation away from periods affected by §51 EEG and into periods where market premium eligibility is preserved. Our analysis shows that recovered market premium payments increase with both battery power and storage duration. Larger and longer-duration systems can recover a greater share of lost market premium revenues. This highlights an often-overlooked benefit of green energy storage projects.
Market Premium Recovery Is Not the Main Value Driver
While market premium recovery can be meaningful, it is important to keep its contribution in perspective. The ability to recover market premiums is only one component of the overall value proposition of a green energy storage system. The primary economic value is typically created elsewhere: through active market optimisation, flexibility and the monetisation of price spreads. In other words: market premium recovery improves project economics, but it is rarely the main reason why a storage project creates value.
What Comes Next?
In our next article, we explore where green energy storage systems generate their largest economic benefits and why flexibility often creates more value than market premium recovery alone.