Fleer, Johannes: Impact analysis of different operation strategies for battery energy storage systems (BESS) providing primary control reserve

Abstract:

In this work, a techno-economic analysis of stationary battery systems providing primary control for grid stabilisation is conducted. The effects of battery design and operation strategies adapted for primary control supply are investigated with regard to costs and parameters relevant for battery aging. Primary control is required to balance the feed-in and use of electricity to/from the grid, thereby ensuring safe and stable grid operation. In Germany, primary control is traded on a separate auction market with specific regulations. These regulations (minimum bid size of 1 MW, contract period of one week) offer the opportunity of a market entry for stationary battery systems and allow for a certain degree of flexibility regarding system configurations and operation strategies. However, little is known about how battery design and operation profiles, resulting from the participation in the primary control market, may affect costs and aging behaviour. Based on simulations of battery operation, various battery designs, which are distinct in terms of capacity, as well as several operation strategies are compared. These operation strategies compared include the state of charge (SoC) bandwidth, within which the battery operates, as well as the purchase of balancing energy from other electricity markets to ensure operation throughout the contract period. Results cover operation profiles in terms of SoC and C-rate distribution over time as well as the numbers of charging and discharging cycles for the various designs and operation strategies.These results lead to substantial conclusions regarding battery lifetimes and economic feasibility of providing primary control through stationary battery systems.