Hydroelectricity

Hawaiian Electric Waiau & Puueo Hydropower

• LOCATION: Hilo, Hawaii (Wailuku River)

• ENERGY SOURCE: Run-of-river water flow

• TECHNOLOGY: Hydraulic turbine generators

• SYSTEM SIZE: 1.15 MW (Waiau), 2.25 MW (Puueo)

• TYPE: As-available

• DESCRIPTION: Hawaiian Electric owns and operates two hydroelectric facilities arranged in tandem along the lower reach of the Wailuku River near Hilo. The Waiau plant was constructed in 1920 and upgraded in 1947. The Puueo plant downstream was built in 1910 and upgraded in 1941. Penstocks (pipes that divert water to the plants) of both facilities were refurbished in 1998. Horizontal-axis, Pelton hydraulic turbines at each plant generate electricity

Wailuku River Hydroelectric Power Company

• LOCATION: Hilo, Hawaii (Wailuku River)

• ENERGY SOURCE: Run-of-river water flow

• TECHNOLOGY: Hydraulic turbine generators

• SYSTEM SIZE: 11 MW

• POWER PURCHASE TYPE: As-available

• DESCRIPTION: The Wailuku River Hydroelectric Power Company plant began commercial operation in 1993. It is located at the junction of the Wailuku River and the Kaloheahewa Stream. Hawaii Island also receives power as available from smaller plants operated by the County Department of Water Supply, Wenko Energy Company, and various farms.