Inertia in Germany is ‘first bankable long-term revenue stream,’ could boost battery storage IRR by 1-2pp

“The introduction of inertia services demonstrates that BESS can contribute essential grid-support functions,” says Marie-Sophie Braun, head of markets & regulatory affairs for TotalEnergies-owned developer Kyon.

Hesel be speaking at the Energy Storage Summit Germany 2026, in two week’s time, on 15-16 September in Berlin, as will Marie-Sophie Braun, head of markets & regulatory affairs for TotalEnergies-owned developer Kyon.

Braun was bullish on the potential of BESS in the new service: “The introduction of inertia services demonstrates that BESS can contribute essential grid-support functions.”

Boost to IRR

Hesel estimates that the new revenue stream could boost the internal rate of returns (IRR) for large-scale BESS in Germany by 1-2 percentage points (pp) depending on the project’s setup.