Electric power plant
Electricity is produced at a an electric power plant. Some fuel source, such as coal, oil, natural gas, or nuclear energy produces heat. The heat is used to boil water to create steam. The steam under high pressure is used to spin a turbine. The spinning turbine interacts with a system of magnets to produce electricity. The electricity is transmitted as moving electrons through a series of wires to homes and business.
Electric Power Plants have a number of components in common and are an interesting study in the various forms and changes of energy necessary to produce electricity.
Boiler Unit: Almost all of power plants operate by heating water in a boiler unit into super heated steam at very high pressures. The source of heat from combustion reactions may vary in fossil fuel plants from the source of fuels such as coal, oil, or natural gas. Biomass or waste plant parts may also be used as a source of fuel. In some areas solid waste incinerators are also used as a source of heat. All of these sources of fuels result in varying amounts of air pollution, as well as, the carbon dioxide ( a gas implicated in global warming problems).
In a nuclear power plant, the fission chain reaction of splitting nuclei provides the source of heat.
Turbine-Generator: The super heated steam is used to spin the blades of a turbine, which in turn is used in the generator to turn a coil of wires within a circular arrangements of magnets. The rotating coil of wire in the magnets results in the generation of electricity.
Cooling Water: After the steam travels through the turbine, it must be cooled and condensed back into liquid water to start the cycle over again. Cooling water can be obtained from a nearby river or lake. The water is returned to the body of water 10 -20 degrees higher in temperature than the intake water. Alternate method is to use a very tall cooling tower, where the evaporation of water falling through the tower provides the cooling effect.
Domestic power supply and safety for handling electricity
Precautions to be taken while working with electricity
- Check for damage on power plugs, wire and other electrical fittings. If found damaged, repair or replace damaged equipment immediately.
- Keep electrical wires of equipment away from hot surfaces to prevent damage of the
- Do not lay electric wires along passage. It can be a trip hazard. Further contact with sharp edges can cause damage to insulation leading to short circuit.
- Know the location of switches/circuit breaker boxes for use in case of an emergency.
- All circuit breakers in the switch board must be clearly labelled for easy identification.
- Access to circuit breakers must not be blocked.
- Extension cords must be used only to supply power temporarily.
- Do not handle electrical equipment when hands, feet or body are wet or perspiring, or when standing on a wet floor.
- Consider all floors as conductive unless covered with insulating matting of suitable type for electrical work.
- Whenever possible, use only one hand when working on circuits or control devices.
- Do not wear rings, metallic watchbands, chains etc. when working with electrical equipment.
Precautions to be taken while using power tools
- Before connecting the tool to the power supply, switch the tool OFF.
- Disconnect power supply before making adjustments.
- The tool must be properly grounded with a 3-wire cord with a 3-prong plug. Use double insulated tools wherever possible.
- Do not use electrical tools in wet conditions or damp locations unless the tool is connected to an Earth Leakage Circuit Breaker.