Post on 16-Apr-2017
Energy and its transformation
INDICE
1 Energy sources.-1.1 Electricity
2 Electric powers plants.-2.1 Conventional power plants.-2.2 Non-conventional power plants.
3 Environmental impact.
1 Energy sources
Household uses : operating household appliances, heating systems etc
Industrial uses: the operation of factories and businesses, construction, etc
Energy sources are natural resources from which different forms of energy are obtained
We can classify energy sources in several ways:
By availability in nature : renewable or non-renewable
By origin: primary or secondary
By environmental impact: clean or polluting
By use: conventional or non-conventional
1.1 Electricity
The possibility of transporting it long distances at a low cost
Its capacity to be easily transformed into other forms of energy
Electricity is the most widely used form of energy in industrialised societies for two reasons
Electric power plants
The turbine converts mechanical energy into the rotating movement of a shaft.
The alternator is connected to the turbine shaft. As the shaft moves,it produces alternating electrical current.
Electrical power plants use an external source of energy to producte electricity.To do this, they rely on a turbine-alternator system.
2.Conventional power plants
Intermal power plants, water is heated in a boiler by the heat generated from the combustion of a fossil fuel.(natural gas...)
Combined cycle power plants obtain electricity as the result of two combined cycles:a cycle that uses air and gas, and a convetional thermal cycle.
2.1.Conventional power plants
Nuclear power plants use a nuclear fission reactor that productes heat to generate the pressurised stem needed to nove the turbine rotor
Hydroelectris power plants use the potential energy provieded by the height of the water stored in a dam, converting it into kinetic energy.
2.2. Non-conventional power plants
Wind farms use the kinectic energy of the wind to move the blades of a rotor at the top of a tower; this is referred to as a wind turbine
Biomass consists of all organic compounds that are produced through natural processes.
Solar power plants use the Sun's energy. There are two types: Photo thermal power plants and Photovoltaic power plants.
Geothermal power plants use the heat found at deep layers in the Earth.
The envioronmental problems caused by convetional power plants have led to the creation and development of non-conventional or alternative energy power plants
3 environmental impact
The exploitation of fossil fuels and nuclear energy leads to the depletion of resources. Furthermore, fuel extraction processes are sometimes harmful to the environment
Petroleum is transported by means of oil pipelines and oil tankers both can have accidents which means the risk of a spill.
Conventional thermal power plants produce air pollution which increases greenhouse effec.
Nuclear power plants are accomponied by the risk of a nuclear accident and nuclear waste.