No. 20: Small-scale hydraulic generation is spreading (November 20, 2011)

The law that asks electric power companies to purchase all electricity generated by renewable energy will be enacted next year, and the move to build a small-scale hydraulic plant through the collaboration between a local government and a private company is spreading. Nomura Agri Planning & Advisory will build a small-scale hydraulic plant in Tochigi Prefecture on trial. The company will install a generation with an output of 10 kW in two locations in the irrigation canal inside the prefecture to conduct feasibility study next spring, and commercialize the technology in 2013. The prefectural government will help the company by simplifying the complicated procedures involved in irrigation right. A subsidiary of Mitsui Mining and Smelting will build a hydraulic plant that generate electricity using water of two rivers running in its premises with an investment of 1 billion yen. Nippon Koei will start to build a hydraulic plant in Kagoshima Prefecture coming December. The plant will have a generation capacity of 460 kW and start operations in April 2013.

Japan has more than 20,000 locations suitable for small-scale hydraulic generation. Although each of them has a generation capacity less than 30,000 kW on average, they together are estimated to have a potential generation capacity of 15 million kW, about the same generation capacity of 15 nuclear power plants. Local governments that support the projects are serious about promoting renewal energy business. Because water volume does not fluctuate greatly, hydraulic generation is more stable than photovoltaic generation and wind generation in terms of output. The Ministry of Economy, Trade and Industry estimates the generation cost of a small-scale hydraulic plant at 10-35 yen per kW depending on the location. To promote small-scale hydraulic generation, the Japanese government is considering revising the river law and deregulating the procedures involved in irrigation right.