German Battery Developers Weigh Flexible Grid Contracts Against Revenue Certainty

Flexible connection agreements are dividing opinion among battery storage developers in Germany, as operators navigate a system where faster grid access often comes at the cost of reduced participation in ancillary services markets.

At the Energy Storage Summit Germany, industry figures debated whether the speed-versus-revenue trade-off embedded in these contracts is workable. A recurring theme was the absence of harmonised rules between distribution and transmission system operators — a gap that many participants said has left developers little choice but to accept imperfect arrangements simply to secure a place in the market.

Georg Gallmetzer, head of Eco Stor, argued that time-to-market is a decisive factor. The company’s Bollingstedt project, developed under a flexible connection agreement, saw revenues reduced by 20 per cent. Despite that shortfall, the project completed its full development cycle and the company finalised its sale to Alpiq. Gallmetzer said the long-term stability built into the contract kept it attractive enough for the incoming investor.

Wilhelm Kivitt of transmission operator 50Hertz offered a system-level caution, noting that some DSOs deploy flexible agreements to manage connection queues and reduce the commercial appeal of projects. He stressed that the public interest lies in channelling as many batteries as possible into ancillary services, with TSOs needing storage at both transmission and distribution level to meet system needs.

Germany’s experience reflects a broader industry tension: the aspiration for fully optimised, digitalised grid management versus the immediate pressure to deploy. For now, the sector appears to be making peace with flexible connection agreements as a practical, if imperfect, path to getting projects built.

Source: Energy Storage News