Fortum has announced it has activated a large set of lithium ion batteries at the Forshuvud hydropower plant located near Borlänge and Dalälven in Dalarna, Sweden, marking the first time batteries have been used in the electricity grid to support hydropower and improve the regulation power.

Forshuvud has been equipped with a large amount of lithium-ion batteries with a total storage capacity of 6.2MWh and a maximum power output of 5MW. The batteries are expected to help reduce the risks of network disturbances as well as reduce wear and tear on the hydropower plant.

Hydropower is the backbone of the Nordic renewable energy system. In Norway, it accounts for 96% of power generation, whilst in Sweden it accounts for approximately 50%. At the same time, the use of other renewables is increasing rapidly in the Nordic countries. Sweden is currently preparing for a transformation of its energy system and a broad political agreement has set a target of 100% renewable energy by 2040. The agreement also states that the transferability of Sweden’s energy to its neighboring countries must increase.

“The fact that there has to be sufficient amount of well-functioning and precise regulation capacity in Nordic power system, the new batteries, will reinforce the regulation power in the Nordic power system. At the same time, we are improving an already green and sustainable energy source,” said Tatu Kulla, Fortum's Head of Business Development.

Thanks to the batteries, frequencies in the grid will be superinduced or drawn back faster and altering power in a matter of seconds. This compensates for increasingly fast changes in the production of electricity caused by, for example, wind power. The batteries will utilize and enhance the hydropower plant’s role as a regulator and take better advantage of capacity regulation, which is one of the main benefits of hydroelectric power.

“This is a unique solution. It means that the supply of energy will be more secure and more sustainable. Fortum always aims to invest in innovations that reinforce our hydroelectric powerplants and that strengthen green energy. We will evaluate this project and our priority is that this technique will be used in other power plants throughout Sweden,” added Toni Kekkinen, VP Hydro.

When the batteries were tested during spring, the results showed that the batteries are performing satisfactory frequency response both in terms of speed and endurance.

The installation in Forshuvud is based on the experience Fortum gained two years ago when it started to experiment with this concept at the combined heat and power plant in Järvenpää, Finland. Approximately €3 million has been invested in this project.