Hydroelectric Power
Hydroelectricity all starts at a dam, where falling water flows down the penstock and rotates a turbine. This turbine is connected to a generator which converts the kinetic energy to electrical energy. The energy from the generator has a very low voltage but to be transported over long distances efficiently, the step up transformers increase it to a higher voltage. This high voltage electricity is carried via grid transmission lines. Terminal stations control the power flow in grid transmission lines and reduce the voltage to be carried in subtransmission lines, which supply power to industries or distribution substations. The distribution substation is a system of transformers, meters, and control and protective devices that reduces the voltage for residential customers, like your home.
Pros: process is safe for humans and environment, renewable resources
Cons: building of dams and plants could affect the environment
Thermal Power
Water within a boiler is heated up and changed into steam. The steam turns the turbine and the kinetic energy from the turbine works the generator. The generator produces electricity and the kinetic energy is converted to electrical energy.
Pros: cheap and easy to find resources
Cons: pollution (greenhouse gases) and non renewable resources
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