Okinawa Yanbaru Seawater Pumped Storage Power Station
Encyclopedia
The is a hydroelectric power station located in Kunigami, Okinawa
, Japan
and operated by the Electric Power Development Company
. It is the world’s first pumped-storage to use seawater for storing energy. Its maximum output is 30 MW.
as its lower reservoir, with effective drop of 136 m and maximum flow of 26 m³/s. Its pipelines and pump turbine are installed underground. Its maximum output is approximately 2.1% of the maximum power demand in the Okinawa Island
recorded on August 3, 2009.
The upper reservoir, artificially excavated, lies approximately 600 m away from the seashore and approximately 150 m above the sea level. It has an octagonal planar shape with its maximum width of 252 m. Its maximum depth is 25 m and its effective storage capacity is 564,000 m³. The entire inner surface of the reservoir is covered with an impermeable liner to prevent seawater from leaking and damaging the surrounding vegetation.
Fiber-reinforced plastic
tubes instead of steel tubes were adopted for the penstock
and the tailrace in order to avoid seawater corrosion and adhesion of barnacle
s. The pump turbine is partially made of stainless steel
resistant to seawater.
A 66 kV line connects the power station with the power grid of The Okinawa Electric Power Company
.
and constructed by the Electric Power Development Company.. A five-year verification operation was conducted since May 16, 1999. The Japan Society of Civil Engineers presented the company an Outstanding Civil Engineering Achievement Award on May 26, 2000 for its construction of the plant. It is now under commercial operation.
Kunigami, Okinawa
is a village located in Kunigami District, Okinawa, Japan.As of 2003, the village has an estimated population of 5,629 and a population density of 28.90 persons per km². The total area is 194.80 km².-External links:*...
, Japan
Japan
Japan is an island nation in East Asia. Located in the Pacific Ocean, it lies to the east of the Sea of Japan, China, North Korea, South Korea and Russia, stretching from the Sea of Okhotsk in the north to the East China Sea and Taiwan in the south...
and operated by the Electric Power Development Company
Electric Power Development Company
The , operating under the brand name J-POWER, formerly , is the largest electric utility in Japan. It mainly produces Electricity from Coal and Hydroelectric Power Stations. It also has a few wind farms and is currently building a nuclear plant in Ohma, Aomori prefecture, that is scheduled to...
. It is the world’s first pumped-storage to use seawater for storing energy. Its maximum output is 30 MW.
Facility
The power station is a pure pumped-storage, using the Philippine SeaPhilippine Sea
The Philippine Sea is a marginal sea east and north of the Philippines occupying an estimated surface area of 2 million mi² on the western part of the North Pacific Ocean...
as its lower reservoir, with effective drop of 136 m and maximum flow of 26 m³/s. Its pipelines and pump turbine are installed underground. Its maximum output is approximately 2.1% of the maximum power demand in the Okinawa Island
Okinawa Island
Okinawa Island is the largest of the Okinawa Islands and the Ryukyu Islands of Japan, and is home to Naha, the capital of Okinawa Prefecture. The island has an area of...
recorded on August 3, 2009.
The upper reservoir, artificially excavated, lies approximately 600 m away from the seashore and approximately 150 m above the sea level. It has an octagonal planar shape with its maximum width of 252 m. Its maximum depth is 25 m and its effective storage capacity is 564,000 m³. The entire inner surface of the reservoir is covered with an impermeable liner to prevent seawater from leaking and damaging the surrounding vegetation.
Fiber-reinforced plastic
Fibre-reinforced plastic
Fibre-reinforced plastic is a composite material made of a polymer matrix reinforced with fibres. The fibres are usually fibreglass, carbon, or aramid, while the polymer is usually an epoxy, vinylester or polyester thermosetting plastic...
tubes instead of steel tubes were adopted for the penstock
Penstock
A penstock is a sluice or gate or intake structure that controls water flow, or an enclosed pipe that delivers water to hydraulic turbines and sewerage systems. It is a term that has been inherited from the technology of wooden watermills....
and the tailrace in order to avoid seawater corrosion and adhesion of barnacle
Barnacle
A barnacle is a type of arthropod belonging to infraclass Cirripedia in the subphylum Crustacea, and is hence related to crabs and lobsters. Barnacles are exclusively marine, and tend to live in shallow and tidal waters, typically in erosive settings. They are sessile suspension feeders, and have...
s. The pump turbine is partially made of stainless steel
Stainless steel
In metallurgy, stainless steel, also known as inox steel or inox from French "inoxydable", is defined as a steel alloy with a minimum of 10.5 or 11% chromium content by mass....
resistant to seawater.
A 66 kV line connects the power station with the power grid of The Okinawa Electric Power Company
Okinawa Electric Power Company
, OEPC or for short, is an electric utility with its exclusive operational area of Okinawa Prefecture, Japan. It is the smallest by electricity sales among Japan’s ten regional power utilities, indeed, its electricity sales is approximately 1⁄40 of that of The Tokyo Electric Power Company, though...
.
History
The power station was a pilot plant funded by the Agency for Natural Resources and EnergyAgency for Natural Resources and Energy
The Agency for Natural Resources and Energy is an agency of Japan' Ministry of Economy, Trade and Industry and is responsible for Japan's policies in regard to energy and natural resources....
and constructed by the Electric Power Development Company.. A five-year verification operation was conducted since May 16, 1999. The Japan Society of Civil Engineers presented the company an Outstanding Civil Engineering Achievement Award on May 26, 2000 for its construction of the plant. It is now under commercial operation.
External links
- Okinawa Yanbaru Seawater Pumped Storage Power Station (Official site, in Japanese)