HYDROPOWER

Hydropower uses the kinetic energy of flowing and falling water to produce electricity. It is an indirect form of solar energy because it is based on the evaporation of water, which is deposited at higher elevations where it can flow to lower elevations in rivers as part of the earth’s solar-powered water cycle. The most common approach to harnessing hydropower is to build a high dam across a large river to create a reservoir. Some of the water stored in the reservoir is allowed to flow through large pipes at controlled rates to spin turbines that produce electricity. Hydropower is the world’s leading renewable energy source used to produce electricity.

The use of microhydropower generators may become an increasingly important way to produce electricity. These are floating turbines, each about the size of an overnight suitcase. They use the power of flowing water to turn rotor blades, which spin a turbine to produce electric current. They can be placed in any stream or river without altering its course to provide electricity at a very low cost with a very low environmental impact.

Advantages:

  • Moderate to high net energy.
  • Large untapped potential.
  • Low-cost electricity.
  • Low emissions of CO2 and other air pollutants in temperate areas.
Disadvantages:

  • Large land disturbance and displacement of people.
  • High CH4 emissions from rapid biomass decay in shallow tropical reservoirs.
  • Disrupts downstream aquatic ecosystems.

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