PHYSICS

Physics

Physics

Pumped Storage Hydroelectric

The physics of Pumped Storage Hydroelectric (PSH) is very simple in principle. There are two water reservoirs on different levels of height connected by tubes and a turbine on the lower level (Green, Goldsmith and Basher, 2008). The turbine is driven to generate electricity when water flows down the tube. The turbine or a pump lifts the water up to store it in the upper reservoir.

The biggest installation is 'Bath County Pumped Storage Station' in United States with 2772MW capacity, followed by 'Guangdong Pumped Storage Power Station' in China with 2400MW generation capacity. Pumped storage hydroelectricity is stored as a form of potential energy and is re-converted when electricity is needed in the grid.Wave power

Along the coast of U.S., there are no significant wave power plants, but U.S. can generate up to 252 million megawatt hours a year from its coast. The world can generate wave-power up to 2TW. Areas with the greatest potential for wave power include the west coast of Europe, north coast of the United Kingdom and the Pacific coast of North and South America, Australia and New Zealand, as well as the coast of South Africa.

One of the key technical issues is how to absorb mechanical energy, which comes to the field with randomized speeds, and electrical energy is suitable for connection to the electricity grid (Serway, Faughn, and Vuille, 2011). The high cost initial investment results in these plants having a long amortization period. Moreover, its use is limited to coastal areas or near the coast, the financial cost to transport the energy from inland locations is quite high. Another downside is the environmental impact of the facilities, which require modification of the landscape for its construction. It must have plenty of space to accommodate the huge turbines, leading to an ecological impact on coastal ecosystems.Tidal Power

Located in South Korea; Sihwa Lake plant is the largest tidal power plant in the world, with a production capacity of 254 MW. The first in-stream tidal power plant is located at Race Rocks, on Southern Vancouver Island. The future expansion of this plant will take place at Nova Scotia. India is planning to develop first commercial tidal-power plant, with 50 MW capacity, in South Asia. The construction will start in early 2012.

The magnitude of the energy dissipated naturally by tides annually is estimated at 22000TWh, which is one-fifth of global energy consumption. Only a fraction of this energy is recoverable, and tidal energy can contribute very minutely in meeting the world needs.

There are few difficulties to generate tidal power. Optimal exploitation of the potential energy requires major adjustments that significantly affect the ecological balance in areas that are fragile, and it is likely that this path will not be much exploited in the future (Cutnell and Johnson, 2004). Methods to capture the kinetic energy of tidal currents are being explored. For them to be usable, the currents must exceed 3 knots for noted periods.

Large Scale Hydropower

'The Three Gorges Dam', China, is currently the largest capacity hydroelectric dam in the world; with around 22.5 ...