Next Kraftwerke and Eco Stor sign tolling deal for 300 MW German BESS

German power marketer Next Kraftwerke and battery storage developer Eco Stor have signed a five-year tolling agreement covering 300 MW/700 MWh of storage capacity at Förderstedt in Saxony-Anhalt, combining an 80% tolled capacity with a 20% merchant allocation.

The flexibility tolling agreement is designed to provide a revenue base for the project’s operation and secure its financing, though the companies did not disclose financial terms. The Förderstedt project is privately financed without public subsidies, with funding provided by investors NIC and X-Elio.

Commissioning is planned in three stages from November 2026, starting with an initial 100 MW block to be traded on day-ahead, intraday, and balancing energy markets. Two further 100 MW blocks will follow, with full commissioning expected in 2027 at 300 MW of power and more than 700 MWh of storage capacity. The system is designed for two full charge and discharge cycles per day.

Under the agreement, Next Kraftwerke will optimize the storage asset across spot and balancing energy markets. The company will also operate under the terms of a flexible grid connection agreement with transmission system operator 50Hertz, including constraints on ramp rates and system services.

The asset is designed to respond to price and grid signals, storing electricity during generation peaks or low-demand periods and discharging during low-generation or high-demand periods. It will also provide frequency response, short-term grid balancing, and reactive power, and can restore electricity supply autonomously in the event of a blackout.

Marc Rühs, CEO of Next Kraftwerke, said the tolling model establishes a new standard in storage marketing and creates reliable conditions for partners, and that the project demonstrates how optimization algorithms and intelligent market integration can work together.

Georg Gallmetzer, managing director of Eco Stor, said the project links technological innovation with clearly defined operational parameters, and that consistently incorporating grid-side requirements such as ramp rates and reserve capacity provision ensures both grid-serving and market-oriented operation. He said the market has already moved well beyond where policy and regulation currently stand.

From pv magazine Deutschland