Fortum to install battery to support grid stability

A battery is to be installed at Fortum's Forshuvud plant, which provides regulating power to the Nordic electricity network.

Fortum is to install the biggest battery to date at its 44 MW Forshuvud hydropower plant on the river Dalälven in central Sweden.

The battery system, with an output of 5 MW and a storage capacity of 6.2 MWh, is designed to improve the plant’s ability to provide regulating power for the Nordic electricity network, the Finland-based energy group disclosed on 28 November. The battery, which will cost about €3 million, is scheduled to be installed and begin operating during the first half of 2019, it added. “The battery’s very quick response time improves the speed and preciseness of the Forshuvud hydropower plant’s regulation, so we will be able to provide even better service to grid companies,” said Martin Lindström, Head of Asset Management Hydro at Fortum.

Fortum noted that chemical batteries can complement the balancing services currently provided by hydropower and reduce wear and tear on the plants’ turbines. “Today the electricity market is kept in balance mainly with hydropower, which can provide balancing flexibly over different time periods, from a few seconds to several months. However, quick balancing causes significant wear to the hydropower plant’s turbines. That’s why the use of batteries is expected to become more common in an energy system that requires increasingly faster balancing,” it explained. “With wind power expected to increase significantly, the electricity network must be more flexible to maintain a consistent balance between production and consumption. Maintaining the correct frequency of the grid is necessary for the operation of the electricity system. Many power plants ramp their power output up or down to keep the network’s frequency at 50 Hz. Balancing may be needed very quickly, even in a matter of a few seconds. The new battery will help to keep the frequency in balance, and the Forshuvud powerplant will recharge the battery with renewable hydropower,” it added.

Forshuvud, which was commissioned in 1990 and expanded in 1998, is one of 39 hydropower plants with a combined installed capacity of 976 MW, in which Fortum holds full or majority ownership and operates on the Dalälven, Sweden’s second longest river. The river that flows from the north of Dalarna and runs into the sea in the Gulf of Bothnia in northern Uppland has a technical hydropower potential of 1420 MW, of which around two thirds has been harnessed to date.