Shopping on line can be easy, simple and save you lots of money. It can also take a lot of your time, frustrate you, and result in unwanted purchases. Now the same can be said for regular high street shopping, but with the vast opportunity presented by the Internet it will pay you to spend a few minutes reading this and understanding how to better optimize your Power Station shopping experience:
1. Compare - without doubt the biggest advantage that the Power Station offers shoppers today is the ability to compare thousands of Power Station at a time. This is a great thing, but not necessarily all the time! Too much can be daunting at times so take advantage of the great comparison sites and where possible let them do the hard work for you.
2. Research - if it has been said it will be on the internet. Ignorance is no longer a justifiable reason for buying the wrong thing. Take the time to research in detail everything that you could possible want to know about
3. Testimonials - don't know anybody that has bought a Power Station? Wrong! If the Power Station is good the internet will let you know. Use the Internet as a friend and get testimonials before you buy.
4. Questions - Got a question about Power Station then search the Forums, FAQ's, Blogs etc. Don't be afraid to ask .....
5. Reputation - Never heard of the company selling Power Station? Don't worry, no reason why you should know every company in the world, but you know someone that does! Use the internet to find out what people are saying about Power Station and build up a picture of their reputation for sales, returns, customer service, delivery etc.
6. Returns - still worried that even after all of the above your Power Station wont be what you want? Check out the returns policy. There is so much competition now that someone, somewhere is bound to offer the terms that you are comfortable with.
7. Feedback - happy with your Power Station then let people know, after all you are depending on others people input in your buying decision, so why not give a little back.
8. Security - check for the yellow padlock on the Power Station site before you buy, and the s after http:/ /i.e. https:// = a secure site
9. Contact - got a question about Power Station, or want to leave a comment then check out the sites contact page. Reputable companies have them and respond.
10. Payment - ready to pay for your Power Station, then use your credit card or PayPal! Be aware of companies that don't accept them, there may be genuine reasons but given the huge amount of choice you have when buying online there is no reason at all not to buy via credit card or PayPal.
in IraqA
power station (also referred to as
generating station or
power plant) is an industrial facility for the
Electricity generation of
electric power.
Power plant is also used to refer to the engine in ships, aircraft and other large vehicles. Some prefer to use the term
energy center because it more accurately describes what the plants do, which is the conversion of other forms of
energy, like
chemical energy,
gravitational potential energy or heat energy into electrical energy. However,
power plant is the most common term in the U.S., while elsewhere
power station and
power plant are both widely used,
power station prevailing in many Commonwealth of Nations and especially in the
United Kingdom.
At the center of nearly all power stations is a
Electrical generator, a rotating machine that converts mechanical energy into electrical energy by creating relative motion between a magnetic field and a conductor. The energy source harnessed to turn the generator varies widely. It depends chiefly on what fuels are easily available and the types of technology that the power company has access to.
Thermal power stations
In thermal power stations, mechanical power is produced by a heat engine, which transforms thermal energy, often from
combustion of a fuel, into rotational energy. Most thermal power stations produce steam, and these are sometimes called steam power stations. About 86% of all electric power is generated by use of steam turbines. Not all thermal energy can be transformed to mechanical power, according to the second law of thermodynamics. Therefore, there is always heat lost to the environment. If this loss is employed as useful heat, for industrial processes or
district heating, the power plant is referred to as a cogeneration power plant or CHP (combined heat-and-power) plant. In countries where district heating is common, there are dedicated heat plants called
heat-only boiler stations. An important class of power stations in the Middle East uses byproduct heat for desalination of water.
Classification
GE H series power generation gas turbineThermal power plants are classified by the type of fuel and the type of prime mover installed.
By fuel
- Nuclear power plants Nuclear Power Plants Information, by International Atomic Energy Agency use a nuclear reactor's heat to operate a steam turbine generator.
- Fossil fuel power plant may also use a steam turbine generator or in the case of natural gas fired plants may use a gas turbine.
- Geothermal power plants use steam extracted from hot underground rocks.
- Renewable energy plants may be fuelled by bagasse, Waste-to-energy plant, landfill methane, or other forms of biomass.
- In integrated steel mills, blast furnace exhaust gas is a low-cost, although low-energy-density, fuel.
- Cogeneration is occasionally concentrated enough to use for power generation, usually in a steam boiler and turbine.
By prime mover
- Steam turbine plants use the dynamic pressure generated by expanding steam to turn the blades of a turbine. Almost all large non-hydro plants use this system.
- Gas turbine plants use the dynamic pressure from flowing gases to directly operate the turbine. Natural-gas fuelled turbine plants can start rapidly and so are used to supply "peak" energy during periods of high demand, though at higher cost than base-loaded plants. These may be comparatively small units, and sometimes completely unmanned, being remotely operated. This type was pioneered by the UK, Princetownhttp://www.swehs.co.uk/docs/news13su.html being the world's first, commissioned in 1959.
- Combined cycle plants have both a gas turbine fired by natural gas, and a steam boiler and steam turbine which use the exhaust gas from the gas turbine to produce electricity. This greatly increases the overall efficiency of the plant, and many new baseload power plants are combined cycle plants fired by natural gas.
- Internal combustion Reciprocating engines are used to provide power for isolated communities and are frequently used for small cogeneration plants. Hospitals, office buildings, industrial plants, and other critical facilities also use them to provide backup power in case of a power outage. These are usually fuelled by diesel oil, heavy oil, natural gas and landfill gas.
- Gas turbine#Micro turbiness, Stirling engine and internal combustion reciprocating engines are low cost solutions for using opportunity fuels, such as landfill gas, digester gas from water treatment plants and waste gas from oil production.
Cooling towers
in China with a hyperbolic cooling tower
Because of the fundamental limits to thermodynamic efficiency of any
Carnot cycle, all thermal power plants produce waste heat as a byproduct of the useful electrical energy produced. Natural draft wet
cooling towers at nuclear power plants and at some large thermal power plants are large hyperbolic
chimney-like structures (as seen in the image at the left) that release the waste heat to the ambient atmosphere by the evaporation of water (lower left image).However, the mechanical induced-draft or forced-draft wet cooling towers (as seen in the image to the right) in many large thermal power plants, Oil refinery, petrochemical,
Geothermal power,
biomass and
trash-to-energy plant use Fan (mechanical) to provide air movement upward through downcoming water and are not hyperbolic chimney-like structures. The induced or forced-draft cooling towers are rectangular, box-like structures filled with a material that enhances the contacting of the upflowing air and the downflowing water. (Includes cooling tower material balance for evaporation emissions and blowdown effluents. Available in many university libraries)
s evaporating water at Ratcliffe Power Plant, UK
In desert areas a dry cooling tower or radiator may be necessary, since the cost of make-up water for evaporative cooling would be prohibitive. These have lower efficiency and higher energy consumption in fans than a wet, evaporative cooling tower.
Where economically and environmentally possible, electric companies prefer to use cooling water from the ocean, or a lake or river, or a cooling pond, instead of a cooling tower. This type of cooling can save the cost of a cooling tower and may have lower energy costs for pumping cooling water through the plant's heat exchangers. However, the waste heat can cause the temperature of the water to rise detectably. Power plants using natural bodies of water for cooling must be designed to prevent intake of organisms into the cooling cycle. A further environmental impact would be organisms that adapt to the warmer plant water and may be injured if the plant shuts down in cold weather.
In recent years, recycled wastewater, or grey water, has been used in cooling towers. The Calpine Riverside and the Calpine Fox power stations in
Wisconsin as well as the Calpine Mankato power station in Minnesota are among these facilities.
Other sources of energy
Other power stations use the energy from wave or
tide motion, Wind power, Solar power or the energy of falling water, hydroelectricity. These types of energy sources are called
renewable energy.
Hydroelectricity
Hydroelectric dams impound a Reservoir (water) of water and release it through one or more water turbines to generate electricity.
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 during the night 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 to produce electric power. Some pumped storage plants are actually not net consumers of electricity because they release some of the water from the lower reservoir downstream, either continuously or in bursts.
Solar
A solar Solar cell power plant converts sunlight into electrical energy, which may need Inverter (electrical) to alternating current for transmission to users. This type of plant does not use rotating machines for energy conversion. Solar thermal electric plants are another type of solar power plant. They direct sunlight using either parabolic troughs or heliostats. Parabolic troughs direct sunlight onto a pipe containing a heat transfer fluid, such as oil, which is then used to boil water, which turns the generator. The central tower type of 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. There is yet another type of solar thermal electric plant. The sunlight strikes the bottom of the pond, warming the lowest layer which is prevented from rising by a salt gradient. A Rankine cycle engine exploits the temperature difference in the layers to produce electricity. Not many solar thermal electric plants have been built. Most of them can be found in the Mojave Desert, although
Sandia National Laboratory, Israel and Spain have also built a few plants.
Wind
Wind turbines can be used to generate electricity in areas with strong, steady winds. Many different designs have been used in the past, but almost all modern turbines being produced today use the Dutch six-bladed, upwind design. Grid-connected wind turbines now being built are much larger than the units installed during the 1970s, and so produce power more cheaply and reliably than earlier models. With larger turbines (on the order of one megawatt), the blades move more slowly than older, smaller, units, which makes them less visually distracting and safer for airborne animals. However, the old turbines can still be seen at some wind farms, particularly at
Altamont Pass and
Tehachapi Pass.
See also
References
External links
- Identification System for Power Stations (KKS)
- Power station diagram
- Power Generation Plants (diagrams)
- Power Plant Reference Books
- Large industrial cooling towers
- Inter-Utility Sub-station Training Assoc.
- APMS: Advanced Plant Management System
- A photo tour of the Zimmer Power Station, Moscow, Ohio (1300 MW Coal Fired)
in IraqA
power station (also referred to as
generating station or
power plant) is an industrial facility for the
Electricity generation of electric power.
Power plant is also used to refer to the engine in ships, aircraft and other large vehicles. Some prefer to use the term
energy center because it more accurately describes what the plants do, which is the conversion of other forms of energy, like
chemical energy,
gravitational potential energy or heat energy into electrical energy. However,
power plant is the most common term in the U.S., while elsewhere
power station and
power plant are both widely used,
power station prevailing in many Commonwealth of Nations and especially in the
United Kingdom.
At the center of nearly all power stations is a Electrical generator, a rotating machine that converts mechanical energy into electrical energy by creating relative motion between a magnetic field and a conductor. The energy source harnessed to turn the generator varies widely. It depends chiefly on what fuels are easily available and the types of technology that the power company has access to.
Thermal power stations
In thermal power stations, mechanical power is produced by a
heat engine, which transforms thermal energy, often from combustion of a fuel, into rotational energy. Most thermal power stations produce steam, and these are sometimes called steam power stations. About 86% of all electric power is generated by use of steam turbines. Not all thermal energy can be transformed to mechanical power, according to the second law of thermodynamics. Therefore, there is always heat lost to the environment. If this loss is employed as useful heat, for industrial processes or district heating, the power plant is referred to as a
cogeneration power plant or CHP (combined heat-and-power) plant. In countries where district heating is common, there are dedicated heat plants called
heat-only boiler stations. An important class of power stations in the Middle East uses byproduct heat for
desalination of water.
Classification
GE H series power generation gas turbineThermal power plants are classified by the type of fuel and the type of prime mover installed.
By fuel
- Nuclear power plants Nuclear Power Plants Information, by International Atomic Energy Agency use a nuclear reactor's heat to operate a steam turbine generator.
- Fossil fuel power plant may also use a steam turbine generator or in the case of natural gas fired plants may use a gas turbine.
- Geothermal power plants use steam extracted from hot underground rocks.
- Renewable energy plants may be fuelled by bagasse, Waste-to-energy plant, landfill methane, or other forms of biomass.
- In integrated steel mills, blast furnace exhaust gas is a low-cost, although low-energy-density, fuel.
- Cogeneration is occasionally concentrated enough to use for power generation, usually in a steam boiler and turbine.
By prime mover
- Steam turbine plants use the dynamic pressure generated by expanding steam to turn the blades of a turbine. Almost all large non-hydro plants use this system.
- Gas turbine plants use the dynamic pressure from flowing gases to directly operate the turbine. Natural-gas fuelled turbine plants can start rapidly and so are used to supply "peak" energy during periods of high demand, though at higher cost than base-loaded plants. These may be comparatively small units, and sometimes completely unmanned, being remotely operated. This type was pioneered by the UK, Princetownhttp://www.swehs.co.uk/docs/news13su.html being the world's first, commissioned in 1959.
- Combined cycle plants have both a gas turbine fired by natural gas, and a steam boiler and steam turbine which use the exhaust gas from the gas turbine to produce electricity. This greatly increases the overall efficiency of the plant, and many new baseload power plants are combined cycle plants fired by natural gas.
- Internal combustion Reciprocating engines are used to provide power for isolated communities and are frequently used for small cogeneration plants. Hospitals, office buildings, industrial plants, and other critical facilities also use them to provide backup power in case of a power outage. These are usually fuelled by diesel oil, heavy oil, natural gas and landfill gas.
- Gas turbine#Micro turbiness, Stirling engine and internal combustion reciprocating engines are low cost solutions for using opportunity fuels, such as landfill gas, digester gas from water treatment plants and waste gas from oil production.
Cooling towers
in China with a hyperbolic cooling tower
Because of the fundamental limits to thermodynamic efficiency of any
Carnot cycle, all thermal power plants produce waste heat as a byproduct of the useful electrical energy produced. Natural draft wet
cooling towers at nuclear power plants and at some large thermal power plants are large hyperbolic chimney-like structures (as seen in the image at the left) that release the waste heat to the ambient atmosphere by the evaporation of water (lower left image).However, the mechanical induced-draft or forced-draft wet cooling towers (as seen in the image to the right) in many large thermal power plants,
Oil refinery,
petrochemical, Geothermal power,
biomass and
trash-to-energy plant use Fan (mechanical) to provide air movement upward through downcoming water and are not hyperbolic chimney-like structures. The induced or forced-draft cooling towers are rectangular, box-like structures filled with a material that enhances the contacting of the upflowing air and the downflowing water. (Includes cooling tower material balance for evaporation emissions and blowdown effluents. Available in many university libraries)
s evaporating water at Ratcliffe Power Plant, UK
In desert areas a dry cooling tower or radiator may be necessary, since the cost of make-up water for evaporative cooling would be prohibitive. These have lower efficiency and higher energy consumption in fans than a wet, evaporative cooling tower.
Where economically and environmentally possible, electric companies prefer to use cooling water from the ocean, or a lake or river, or a cooling pond, instead of a cooling tower. This type of cooling can save the cost of a cooling tower and may have lower energy costs for pumping cooling water through the plant's
heat exchangers. However, the waste heat can cause the temperature of the water to rise detectably. Power plants using natural bodies of water for cooling must be designed to prevent intake of organisms into the cooling cycle. A further environmental impact would be organisms that adapt to the warmer plant water and may be injured if the plant shuts down in cold weather.
In recent years, recycled wastewater, or grey water, has been used in cooling towers. The Calpine Riverside and the Calpine Fox power stations in Wisconsin as well as the Calpine Mankato power station in
Minnesota are among these facilities.
Other sources of energy
Other power stations use the energy from
wave or tide motion, Wind power,
Solar power or the energy of falling water,
hydroelectricity. These types of energy sources are called renewable energy.
Hydroelectricity
Hydroelectric dams impound a
Reservoir (water) of water and release it through one or more
water turbines to generate electricity.
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 during the night 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 to produce electric power. Some pumped storage plants are actually not net consumers of electricity because they release some of the water from the lower reservoir downstream, either continuously or in bursts.
Solar
A solar Solar cell power plant converts sunlight into electrical energy, which may need
Inverter (electrical) to alternating current for transmission to users. This type of plant does not use rotating machines for energy conversion. Solar thermal electric plants are another type of solar power plant. They direct sunlight using either parabolic troughs or heliostats. Parabolic troughs direct sunlight onto a pipe containing a heat transfer fluid, such as oil, which is then used to boil water, which turns the generator. The central tower type of 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. There is yet another type of solar thermal electric plant. The sunlight strikes the bottom of the pond, warming the lowest layer which is prevented from rising by a salt gradient. A
Rankine cycle engine exploits the temperature difference in the layers to produce electricity. Not many solar thermal electric plants have been built. Most of them can be found in the Mojave Desert, although
Sandia National Laboratory, Israel and Spain have also built a few plants.
Wind
Wind turbines can be used to generate electricity in areas with strong, steady winds. Many different designs have been used in the past, but almost all modern turbines being produced today use the Dutch six-bladed, upwind design. Grid-connected wind turbines now being built are much larger than the units installed during the 1970s, and so produce power more cheaply and reliably than earlier models. With larger turbines (on the order of one megawatt), the blades move more slowly than older, smaller, units, which makes them less visually distracting and safer for airborne animals. However, the old turbines can still be seen at some wind farms, particularly at
Altamont Pass and
Tehachapi Pass.
See also
References
External links
- Identification System for Power Stations (KKS)
- Power station diagram
- Power Generation Plants (diagrams)
- Power Plant Reference Books
- Large industrial cooling towers
- Inter-Utility Sub-station Training Assoc.
- APMS: Advanced Plant Management System
- A photo tour of the Zimmer Power Station, Moscow, Ohio (1300 MW Coal Fired)
Tilbury Power Station - - npower
Welcome to Tilbury Power Station (Coal Fired) and the Energy and Environment Centre. Tilbury is one of three of npower's coal fired power stations.
Battersea Power Station Community Group web site
Battersea Power Station Community Group campaigns to preserve Battersea Power Station and for a phased development of the site that reflects the needs of the local community.
Barking Power Station
Home page of barking power station dagenham ... Barking Power Station was constructed between 1992 and 1995 and was the first major generating station in London for many years.
PowerStation
Welcome to POWER STATION. Located in Tewkesbury Gloucestershire POWER STATION is a one stop performance car service and tuning centre. Formed in 1998 by Dirk Hale and Rich Benton ...
Power FM Radio, British radio station, Tenerife, Gran Canaria ...
A British radio station broadcast from the Canary Islands with music, news and sports coverage. Online listening available through RealPlayer.
Power Station Effects - from Pisces Conservation
An independent ecological consultancy and software house, specialists in software for ecological and environmental analysis and recording
First Hydro Dinorwig Power Station
First Hydro Company (owner) presentation about station. Pictures, facts, and figures.
Aberthaw Power Station - - npower
Welcome to Aberthaw Power Station (Coal Fired) Aberthaw is one of three of npower's coal fired power stations. In line with the Government's renewable energy obligation which came ...
Battersea Power Station
Battersea Power Station ... Considered the greatest landmark South of the Thames by the many people who
Fawley power station
