A 2-hour BESS with a full grid connection in France earned €328k/MW/yr over the twelve months to October 2026. Of Modo Energy's European benchmarks, only Poland paid more.

75% of the French revenue came from aFRR, the automatic frequency restoration reserve, with 59% from holding aFRR capacity and 16% from the energy delivered.

Two-thirds of the aFRR revenue came from the summer months (April to September). This is when the French transmission operator RTE raised the upward aFRR it bought over the evening peak from 800 MW to 1,500 MW. Upward aFRR in that block paid five times the rest of the day: €125/MW/h against €24/MW/h.

A 2-hour BESS earned 51% more than a 1-hour one because its extra energy lets it take part in far more aFRR. A 4-hour BESS earned 27% more than a 2-hour BESS, mostly from day-ahead trading and aFRR energy. The methodology explains how the benchmark splits each MW between markets.

Key takeaways

• France is the second-best-paying market among Modo Energy's European benchmarks. A 2-hour BESS earned €328k/MW/yr, a 4-hour BESS €417k/MW/yr over the twelve months to October 2026.
• In January 2026, the energy requirements of aFRR capacity changed. As a result, a 1-hour BESS sold 80% more aFRR capacity in February than in January.
• Summer evenings carried aFRR capacity revenue. From April to September, upward aFRR in the 16:00 to 20:00 block paid €125/MW/h.

How much does a French BESS earn?

Among the European markets, Modo Energy benchmarks show that only Poland paid a BESS more than France. aFRR capacity makes the difference. It paid a French 2-hour BESS €192k/MW/yr and €370k in Poland, against €100k to €123k in the Netherlands, Germany and Spain.