Pumped Storage

Pumped Storage Hydroelectric Schemes | Further Information | References

Pumped Storage Hydroelectric Schemes

A large number of new hydroelectric projects are of the pumped storage type. Each station re-uses the water which passes through it, by storing it in catchment areas below the station and then pumping it back up to the higher catchment dams above the station in a closed circuit arrangement. This pumping is carried out in ‘off-peak’ times when there is a surplus of power available from coal, oil, or gas fueled stations. In many countries nuclear power is used for off-peak pumping.

When pumping is required, a reversal of roles occurs. The generator operates as an electric motor, receiving electricity from a nearby power station and operates the turbine as a pump. The turbine receives energy instead of delivering it. However, in some pumped storage schemes there are two sets of equipment, one set for generating and the other for pumping. The use of pumped storage increases the total amount of power generated by the hydro power station, however, this increase is not renewable energy. The pumps are run by non-renewable sources, allowing excess electrical energy to be stored as the potential energy, as the water is raised to the height of the dam. The amount of renewable energy produced by the hydro power station remains the same.

A number of Asian countries have major pumped storage development programs. In Korea, the Korea Midland Power Co Ltd (KOMIPO), has a 1,000 MW pumped storage power plant under construction at Yangyang. Korea Southeast Power Co Ltd (KOSEPCO) operates a 600-MW pumped storage hydro plant and in 2004 the company finished a 800 MW pumped storage plant at Yecheon. Korea Western Power Co Ltd (KWP) operates the 600 MW Samrangjin pumped storage plant and a 600 MW pumped storage plant at Cheongsong is under construction. The Korean Southern Power Co (KOSPO) operates the 400-MW Cheongpyong pumped storage plant and Korea East-West Power Co (EWP) operates the 700-MW Sanchung pumped storage plant (Platts, 2005).

In Vietnam in 2005, the state owned power company Vietnam Electricity, published its ten year plans for three 1200 MW pumped storage plants to be built at Bac Ai, Phu Yen Dong, and Phu Yen Tay. At an estimated cost of US$2.3 billion, the three plants are designed to assist meeting the peak demand in the country. (Wilmington Media Ltd, 2005). Thailand’s 500 MW pumped storage facility in Lam Takhong, was brought on line in 2002 and is the first and largest underground powerhouse in the country, at a depth of 350 metres. (EGAT, 2006).

China however, boasts the Tianhuangping power station (see Figure 1). This is the largest pumped storage hydro facility in Asia and the third largest in the world, with a capacity of 1.8 GW, comprising of six 306 MW turbines. China now has 15 GW of pumped storage plants either existing, under construction, or in the planning stage (Power-Technology, 2006).

Figure 1 The Tianhuangping Project in China is Asia’s largest pumped storage plant. (courtesy of Power-technology.com).

Further Information

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APACE

The International Journal on Hydropower and Dams

International Energy Outlook 2005

World Energy Council - Survey of Energy Resources

International Association for Small Hydro

References

EGAT. 2006, “Hydroelectric dams in the Northeastern Region” (Online) http://www.egat.co.th/english/dams/hydroelectric_dam.htm (Accessed 23 February 2007).

Power Technology 2006, “Ertan Hydropower Plant, Yalong River, China” (Online) http://www.power-technology.com/projects/ertan/ (Accessed 23 February 2007).

Power Technology 2006, “Tianhuangping pumped-storage Hydro Plant, China” (Online) http://www.power-technology.com/projects/tianhuangping/ (Accessed 23 February 2007).

Platts. 2005, “Platts UDI Country Profile – South Korea” (Online) http://apps5.oingo.com/apps/domainpark/domainpark.cgi?client=netw8744&s=ENERGYIT.COM (Accessed 23 February 2007).

Wilmington Media Ltd, International Water Power and Dam Construction. 2005, “Southeast Asia turns back to Hydro” (Online) http://www.waterpowermagazine.com/story.asp?sectioncode=166&storyCode=2032402 (Accessed 23 February 2007).