Electricity Generation is the process of creating electricity from other forms of energy.
The fundamental principles of electricity generation were discovered during the 1820s and early 1830s by the British scientist Michael Faraday. His basic method is still used today: electric is generated by the movement of a loop of wire, or disc of copper between the poles of a magnet.
A. NON-RENEWABLE RESOURCES ENERGY - POWER PLANT
A non-renewable resource is a natural resource that cannot be produced, re-grown, regenerated, or reused on a scale which can sustain its consumption rate. These resources often exist in a fixed amount, or are consumed much faster than nature can recreate them.
Fossil fuel (such as coal, petroleum and natural gas) and nuclear power are examples.
Nature resources such as coal, petroleum, oil and natural gas take thousands of years to form naturally and cannot be replaced as fast as they are being consumed. Eventually natural resources will become too costly to harvest and humanity will need to find other sources of energy. At present, the main energy sources used by humans are non-renewable as they are cheap to produce.
Fossil Fuel Power Plant
In this plant, the chemical energy stored in fossil fuels (such as coal, fuel oil, natural gas or oil shale) and oxygen of the air is converted successively into thermal energy, mechanical energy and finally, electrical energy for continuous use and distribution across a wide geographical area.
Environmental Impacts
The world’s power demands are expected to rise 60% by 2030. With the worldwide total of active coal plants over 50,000 and rising, the International Energy agency (IEA) estimates that fossil fuels will account for 85% of the energy market by 2030.
World organizations and international agencies like the IEA are concerned about the environmental impact of burning fossil fuels, and coal in particular. The combustion of coal contributes the most to acid rain and air pollution, and has been connected with global warming, due to the chemical composition of coal and the difficulties of removing the impurities from this solid fuel prior to its combustion. Acid rain is caused by the emission of nitrogen oxides and sulfur dioxide into the air. These they may be only mildly acidic, yet when they react with the atmosphere, they create acidic compounds (such as sulfurous acid, nitric acid, and sulfuric acid) that fall as rain, hence the term acid rain. In Europe and the USA, stricter emission laws and decline in heavy industries have reduced the environmental hazards associated with this problem, leading to lower emissions after their peak in 1960s.
Carbon Dioxide
Electricity generation using carbon based fuels is responsible for a large fraction of carbon dioxide (CO2) emissions worldwide; and for 41% of U.S. man-made carbon dioxide emissions. Of fossil fuels, coal combustion in thermal power stations result in greater amounts of carbon dioxide emissions per unit of electricity generated while oil produces less and natural gas produces the least.
Increased concentration of carbon dioxide in the atmosphere causes global warming; concern over the rate of climate change has led to targets to stabilize or reduce carbon dioxide and other greenhouse gas (GHG) emissions by between 25 and 40% by 2020.
Particulate matter (solid or liquid suspended in a gas or liquid)
Another problem related to coal combustion is the emission of particulates that have a serious impact on public health. Studies have shown that exposure to particulate matter is related to an increase of  respiratory and cardiac mortality. Particulate matter can irritate small airways in the lungs, which can lead to increased problems with asthma, chronic bronchitis, airway obstruction, and gas exchange.
There are several methods of helping to reduce the particular matter emissions from coal-fired plants:
- A bag house.
- An electrostatic precipitator (ESP).
- Cyclone collector
Mohave Power Station, a 1,580 MW coal power plant near Laughlin, Nevada, out of service since 2005 due to environmental restrictions
B. RENEWBALE ANERGY - OTHER SOURCES OF ENERGY
Renewable resources are replaced by natural processes given a reasonable amount of time. Soil, water, forests, plants and animals are all renewable resources as long as they are property conserved.
Solar, wind, wave and geothermal energies are based on renewable resources. Renewable resources such as the movement of water (hydropower, including tidal power; ocean surface waves used for wave power), wind (used for wind power), geothermal heat (used for geothermal power); and  radiant energy (used for solar power) are practically infinite and cannot be depleted, unlike their non-renewable counterparts, which are likely to run out if not used wisely.
Hydroelectricity – Hydroelectric dams impound a reservoir of water and release it through one or more water turbines to generate electricity
The Three Gorges Dam in China, the largest hydro-electric power station in the world.
Pumped storage
A pumped storage hydroelectric power plant is a net consumer of energy but decreases the price of electricity. Water is pumped to a high reservoir when the demand, and price, for electricity is low.  During hours of peak demand, when the price of electricity is high, the stored water is released through turbines to produce electric power
The upper reservoir (Llyn Stwlan) and dam of the Ffestiniog Pumped Storage Scheme in north Wales. The lower power station has four water turbines which generate 360 MW of electricity within 60 seconds of the need arising. The size of the dam can be judged from the car parked below.
Solar Power
A solar photovoltaic power plant uses photovoltaic cells to convert sunlight into direct current electricity using the photoelectric effect. This type of plant does not use rotating machines for energy conversion.
Nellis Solar Power Plant in the United States.
Solar thermal power plants
Solar thermal power plants are another type of solar power plants. They use either parabolic troughs or heliostats to direct sunlight onto a pipe containing a heat transfer fluid, such as oil. The heated oil is then used to boil water into steam, which turns a turbine that drives an electrical generator. The central tower type of solar thermal power plant uses hundreds or thousands of mirrors, depending on size, to direct sunlight onto a receiver on top of a tower. Again, the heat is used to produce steam to turn turbines that drive electrical generators.
There is yet another type of solar thermal electric plant. The sunlight strikes the bottom of a water pond, warming the lowest layer of water which is prevented from rising by a salt gradient. A Ranking cycle engine exploits the temperature difference in the water layers to produce electricity.
Wind turbine
Wind turbines can be used to generate electricity in areas with  strong, steady winds, sometimes offshore. Many different designs have been used in the past, but almost all modern turbines being produced today use a three-bladed, upwind design. Grid-connected wind turbines now being built are much larger than the units installed during the 1070s, and so produce power more cheaply and reliably than earlier models. With larger turbines, the blades move more slowly than older, smaller units, which make them less visually distracting and safer for airborne animals.
Wind turbine in front of a thermal power station in Amsterdam, the Netherlands.
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