Contrary to expectations and a previous increase, Germany saw a 23% decrease in negative price hours, falling from 389 to 299 in the first half of 2026 compared to the same period last year. This trend bucks the general European pattern, as evidenced by France, which saw a 14% increase in negative price hours during the same period. Despite this reduction in negative price occurrences, Germany's commercial curtailment of renewable energy paradoxically increased by 20%, rising from 1,216 GWh to 1,463 GWh. This means that significantly more renewable generation was switched off when prices dropped below zero.
The increase in Germany's commercial curtailment, despite fewer negative price hours, is attributed to changes in market design and subsidy regimes. Specifically, the "Solar Peak Act," introduced in February 2025, removed guaranteed subsidy top-ups for newly built renewable assets as soon as wholesale prices turned negative, creating a strong commercial incentive for operators to cease generation rather than operate at a loss. Additionally, Germany's shift to quarter-hourly day-ahead auctions last October has led to more frequent, albeit shorter, periods of negative prices. This national market design, rather than renewable growth alone, increasingly influenced commercial curtailment.
While Germany's negative price hours decreased, other European countries like Spain and France saw significant increases in sub-zero price periods in the first half of 2026. Spain's negative hourly contracts more than tripled to 381, and France's negative price hours nearly doubled. These occurrences are often linked to surges in solar output exceeding demand, particularly around midday. However, Germany's unique market mechanisms have led to a distinct outcome, highlighting the impact of national policies on renewable energy integration and curtailment.
Experts emphasize the urgent need for investment in storage and flexible technologies, such as battery storage and smart meters, to better manage increasing renewable energy generation and prevent curtailment. Commercial and industrial battery storage is projected to nearly triple from 9 GWh in 2026 to 24 GWh by 2028, but even more investment is deemed necessary. These solutions would help absorb surplus renewable energy, shift it to times of higher demand, and reduce the need for operators to switch off clean energy sources, thereby enhancing the overall stability and efficiency of the electricity grid.
