Prius EV Parts Used to Lower Cost of Small Hydroelectric Generation

2019/03/02 22:10
Sousuke Kudou, technical writer

Tohoku Small Hydropower Co Ltd announced Feb 19, 2019, that it will develop small hydroelectric generation facilities by reusing the used HV unit of the Prius hybrid vehicle (HV).

It enables to reduce the high costs of generators and control devices. The company aims to commercialize the project within fiscal 2019.

Tohoku Small Hydropower (Akita City) is a company that designs and manufactures small hydroelectric generation devices.

The motor of the HV unit will be used as a generator, and its inverter and controller will be used as output control devices. Based on the motor capacity, the rated output of the facilities was set at 10kW. Also, expanding the application by serial and parallel arrangements, the company expects a market for less-than-50kW power plants, which are connected to low-voltage power transmission lines of power companies.

Tohoku Small Hydropower will reduce the cost of the electrical device cost of hydroelectric generation facilities by about 90% (in-house comparison) by reusing the HV unit. Also, the company aims to develop a low-cost water turbine supporting advanced operation control (variable speed operation) and reduce costs by changing the manufacturing method of turbine blade. It aims to sell the entire system at a price of ¥600,000 (approx US$5,369) per kilowatt.

Based on the costs calculated by Japan's Ministry of Economy, Trade and Industry (METI), in the case of small hydroelectric generation with an output less than 100kW, the construction cost is ¥1 million per kilowatt. On the other hand, the cost of less-than-200kW small hydroelectric power plants (197 cases) is ¥3.07 million per kilowatt on average (median value: ¥1.94 million). So, the smaller the power generation output, the higher the cost tends to be.

Tohoku Small Hydropower will engage in research and development in collaboration with Toyota Tsusho Corp and Waseda University. Toyota Tsusho will be responsible for (1) the supply of the EV unit of the Prius HV, (2) check/evaluation in fatigue tests and (3) the application of the feedback from the variable-speed control operation to control devices. Waseda University will conduct fatigue tests by using a device for testing an axial-flow turbine model and research and develop a low-cost water turbine by using variable-speed operation control and changing manufacturing methods.

Tohoku Small Hydropower targets the business at water supply facilities and irrigation facilities in Japan as well as overseas markets such as in Middle East and Southeast Asia. The company aims to sell 10 units in Japan in the first year and 50 units in Japan and 450 units outside Japan (500 units in total) in the sixth year and achieve a cumulative unit sales of 1,140 in six years.