What were the striking figures on the electricity markets this month?
“Mayday, Mayday – it’s May Day…” – and the market delivered exactly that signal. On 1st of May, day-ahead prices tested the lower limits, to the point where power consumers once again earned money by consuming electricity. What stood out even more was how little it now takes to move prices dramatically. In France, a marginal shift of ~200 MW was enough to swing prices from around -30 €/MWh down to nearly -500 €/MWh – highlighting just how tight the balancing the grid has become.
After this extreme start, the rest of the month stabilised somewhat, with mostly moderately negative prices – a noticeable shift compared to previous periods
What are the possible reasons for this market behavior?
Two factors shaped the market: On the one hand, renewables met low demand. Public holidays and weekends structurally reduced consumption, while strong PV output created frequent surplus situations. With markets clearing close to zero, even minor forecast deviations increasingly determined whether prices remained positive or dropped sharply into negative territory.
On the other hand, flexibility was often missing when it mattered most. When oversupply hit, there was insufficient responsive demand or storage to absorb it leading to rapid price drops. Seasonal effects added to this dynamic: rising temperatures slightly reduced PV efficiency, contributing to the more moderate negative price levels observed later in the month.
At the same time, regulatory developments are shaping market behaviour and are worth highlighting. The AgNes reform is pointing towards future grid fees for BESS will be based on connected capacity and will be modeled after the grid fees for generators; while grid fee exemption for BESS projects commissioned before August 2029 is planned. With dynamic grid fees postponed to 2030/33 and the transition away from atypical grid usage alongside adjustments to the 7,000-hour rule, flexibility is becoming even more central to future system design.
What do you expect for the next month?
With summer gaining momentum, we expect continued volatility around zero, as markets react more sensitively to even marginal shifts in supply and demand. Flexibility remains the critical bottleneck, ultimately determining who captures value. At the same time, increasing regulatory clarity is accelerating investment decisions, particularly in battery storage and thereby expanding the flexibility available to the grid and markets.
