The large storage battery system validation project by Hokkaido Electric Power Co Inc (HEPCO) at the Minami-Hayakita Substation is getting into full swing.

The redox flow battery manufactured by Sumitomo Electric Industries Ltd (SEI), which was installed at the substation, features an output of 15MW and a capacity of 60MWh. It is one of the largest redox flow batteries currently operating in the world.

The results of the validation project will be utilized to increase the framework for new grid connection for wind power, under the condition that storage batteries are attached to the facilities, for example, aiming to expand the introduction of fluctuating renewable energies.

Hometown of famous racehorses becoming the Mecca of large storage batteries

Abira Town in Hokkaido, which is known for the cheese and melons it produces, is also known as a town of racehorses; the famous racehorse "Deep Impact" was raised there. The town is now seeing a concentration of advanced energy facilities.

The "Softbank Tomatoh Abira Solar Park," a 111MW mega (large-scale) solar power plant, started operation in December 2015. It is the second largest among the power stations currently operating in Japan. At present, a mega solar power plant attached with a 64MW storage battery is under construction on a site adjacent to the solar park. A huge storage battery with 17.5MWh capacity and 34MW output will be operated to smooth output fluctuations from the mega solar power plants. The storage battery is expected to be the largest in Japan among storage batteries attached to mega solar power plants.

A huge storage battery, which is about three times the capacity of the one mentioned above, is actually in operation in Abira Town. It is the facility for the large storage battery system validation project, which was started in December 2016 at the HEPCO Minami-Hayakita Substation by HEPCO and SEI (Fig. 1 & 2).

Fig. 1: The building accommodates the redox flow battery installed at the Minami-Hayakita Substation. (source: Nikkei BP)

Fig. 2: Model of the storage battery building (source: Nikkei BP)

The "redox flow battery" manufactured by SEI was used. The battery, featuring 15MW output and 60MWh capacity, is the largest-scale redox flow battery in operation in the world.

The battery is used for validation, aiming for the stable operation of power grids throughout Hokkaido. HEPCO will validate the performance of the battery to control fluctuations in the output of wind power and solar power facilities and develop optimum control technology by conducting the validation for about three years.