Under the contract, which is valued at approximately $500m, Toshiba will replace six 312MW pump turbines and upgrades motor generators and associated equipment and will boost output up to 50MW per unit.

Installation of the new equipment will start in June 2013 and all units are expected to be commissioned and on line by the end of 2019.

Design engineering for the project will be done at Toshiba’s Keihin Product Operations in Japan, and most of the equipment will be manufactured at Toshiba Hydro Power, a consolidated subsidiary of Toshiba in China.

Pumped storage hydroelectric generation supports electricity utilities in load balancing to meet fluctuations in electricity demand. Energy is essentially stored as the water that drives the turbines, Toshiba said.

Detroit Edison owns 49% of the pumped-storage hydroelectric power plant, while the Consumers Energy owns the other 51%.