Pumped-storage power plants

A pump or compressor does work on a fluid in order to increase the fluid s pressure, elevation, velocity, or internal energy. A fluid engine or turbine extracts work from a fluid by lowering its pressure, elevation, velocity, or internal energy. These definitions are the reverse of each other, so some devices could serve as pumps or as fluid engines, depending on what way they were run. Tidal power plants and pumped storage power plants use the same device as a pump for part of the day and as a turbine for another part of the day. 

Hydraulic power systems include both hydroelectric and pumped storage hydroelectric plants. In both cases, water is directed from a dam through a series of tapering pipes to rotate turbines and create electricity. In principle, the potential energy held in the dam converts into kinetic energy when it flows through the pipes (Fig. 3.23). 

There is a whole range of accumulation systems, yet only a few of them have found their large scale use in practice. Such systems include, for example, the pumped-storage hydro plants, which can be classified as centralised accumulation systems embedded into the transmission system. Other accumulation systems usually work at lower voltage levels with lower accumulation capacity so that these can be classified as decentralised, including, for example, lead accumulators used as backup in power plants and industrial sites. 

Gjorgiev, B., KanCev, D. Cepin, M., 2012. A new perspective in nuclear power plant safety considering pumped-storage hydro plant. 11th International Probabilistic Safety Assessment and Management Conference and the Annual European Safety and Reliability Conference 2012, PSAMll ESREL2012, 5) 3705-3713. 

Number 3 fuel oil (30° API) is transferred from a storage tank at 60°F to a feed tank in a power plant at a rate of 2000 bbl/day. Both tanks are open to the atmosphere, and they are connected by a pipeline containing 1200 ft equivalent length of 1 fin. sch 40 steel pipe and fittings. The level in the feed tank is 20 ft higher than that in the storage tank, and the transfer pump is 60% efficient. 

The first is the "use it or lose it" principle. Electrical power itself cannot be stored in its pure form it needs to be converted to something else. Just as surplus nuclear and gas-fired power stations may store unused power by using it to pump water back up inside a damper as part of an integrated electrical storage system in combination with a hydroelectric power plant, hydrogen can be similarly used to store unused electrical power. 

Angeles, for example, spent 220 million dollars to bring Colorado River water more than 300 miles from Parker Dam. Ohio, with some 400 reservoirs already, plans more. Texas has more than 40 major surface storage facilities with a total capacity of over 13 million acre-ft. The U.S. Bureau of Reclamation now proposes its 3 billion dollar basin development plan for California s Central Valley applying the multiple-purpose philosophy to the entire basin, the bureau envisions 38 reservoirs, plus dams, power plants, transmission lines, pumping stations, and hundreds of miles of transfer canals. This plan would conserve the water resources of the San Joaquin and Sacramento Rivers and of the Central Valley Basin as a whole. 

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