Shiromaru Power Plant
The Shiromaru Power Plant is annexed to the Shiromaru Reservoir Dam.
Before 2000, a certain amount of water used to be released from the gate of the Shiromaru Reservoir Dam in order to maintain the river functionalities of the Tama River from the Shiromaru Reservoir to Tamagawa Power Plant No.3 and for sightseeing purposes. To efficiently use this release water, the Shiromaru Power Plant was built. In consideration of the surrounding environment, the majority of this power plant lies underground.
| Date of start of operation | November 2000 |
|---|---|
| Generation method | Dam |
| Catchment area | 397.0km2 |
| Maximum output | 1,100kW |
| Maximum quantity of water used | 5.30m3/s |
| Maximum effective drop height | 24.05m |
Elevator heading to the water turbine generator room located approx. 40 m underground
Video for approx. 15 seconds
| Water wheel | Horizontal Francis turbine Output of 1,114 kW, 1 unit Output of 160 kW, 1 unit Total of 2 units |
|---|---|
| Generator | Horizontal three-phase synchronous generator Output of 1,100 kVA Voltage of 6,600 V 1 unit |
| Principal transformer | Three-phase core-type indoor dry self-cooled mold transformer Capacity of 1,110 kVA 1 unit |
| Principal interrupter | Vacuum circuit breaker Voltage of 7.2 kV Current of 600 A Interrupting current: 12.5 kA 1 unit |
The Shiromaru Power Plant has two water wheels of different sizes per generator.
The large water wheel, which uses water at approx. 5 m2/s, is used in the daytime from spring to fall during which water is released for sightseers. The small water wheel, which uses water at approx. 1 m2/s, is used at night time and in winter during which water is released for maintenance purposes.
Two water wheels and one generator
Video for approx. 10 seconds
Power plant with utilization of the drainage channel space used for construction of the dam
