ENERGY
Hydro Energy
Hydro energy is considered renewable because the energy from the sun powers the global hydrologic cycle. Energy from the sun evaporates water in the oceans and rivers and draws it upward as water vapour. When the water vapour reaches the cooler air in the atmosphere, it condenses and forms clouds. The moisture eventually falls to the earth as rain or snow, replenishing the water in the oceans and rivers. Gravity drives the water, moving it from high ground to low ground. The force of moving water can be extremely powerful.
Hydropower plants capture the kinetic energy of falling water to generate electricity. Flowing or falling water rotates turbines and generators where kinetic energy is converted to mechanical then electrical energy. The turbines and generators are installed either in or adjacent to dams. Alternatively, pipelines known as penstocks are used to carry water under pressure to the turbines and generators in the hydropower plant.
