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electricity project

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bob electric

on 29 April 2010

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Transcript of electricity project

Electricity reserch project! sources of electical energy coal: The energy in coal originally came from the sun. coal is crushed into really small dust particles and then burnt. Coal is made out if pehestoric plants. pros on fossil fuels:
-you can make large amounts of energy for really cheep.
-energy could be made anywhere as long as you can transport the fossil fuels.
cons on fossil fuels:
-Many fossil fules are needed to creat enough energy for all of us to use.
-Fossil fuels can not be renewed, and we may run out of them.
-when fossil fuels are burnt, carbon dioxide is created and is a part of the green house effect
-sulfer dioxcide can be made by fossile fuels and can cause acid rain
solar power: Solar power is a good way to generate clean renewable energy. A good example is a solar panel. Solar panels work by collecting solar radiation from the sun. They are made up of sveral solar cells, they work kind of like a semi conductor. Coal provides around 28% of our energy, and oil provides 40%. Mind you, this figure is bound to have changed since this page was written, so check the figures if you want to quote them.

Burning coal produces sulphur dioxide, an acidic gas that contributes to the formation of acid rain. This can be largely avoided using "flue gas desulphurisation" to clean up the gases before they are released into the atmosphere. This method uses limestone, and produces gypsum for the building industry as a by-product. However, it uses a lot of limestone
Fossils into fuels:
Crude oil, natural gas and coal are fossil fuels. Fossil fuels are very precious resources because they are non-renewable (once they're used, that's it!). We can also make lots of organic chemicals from them, needed to make products such as paints, detergents, polymers (including plastics), cosmetics and some medicines.

Fossil fuels were formed from the fossillized remains of dead plants and animals that once lived millions of years ago. Oil and natural gas are the products of the deep burial and decomposition of dead plants and animals. Heat and pressure, in the absence of oxygen, transform the decomposed material into tiny pockets of gas and crude oil. The oil and gas then migrates through the pores in the rocks to eventually collect in reservoirs.

Coal comes mainly from dead plants which have been buried and compacted beneath sediments. Most coal originated as peat in ancient swamps created many millions of years ago.
What is crude oil?
Crude oil is a complex mixture of hydrocarbons with small amounts of other chemicals such as sulphor. The crude oil is useless as a mixture and must be sent to an oil refinery to be separated. Crude oils from different parts of the world, or even from different depths in the same oilfield, contain different mixtures of hydrocarbons and other compounds. This is why they vary from light coloured volatile liquids to thick, dark oils.
What is natural gas?
Natural gas is a mixture of hydrocarbons with small molecules. These molecules are made of atoms of carbon and hydrogen. For example, natural gas used in the home is mainly methane, CH 4.
What is a hydrocarbon?
Hydrocarbons only contain hydrogen and carbon atoms. There are two main chemical families of hydrocarbons - the alkenes and the alkenes. Thousands of synthetic products can be manufactured from hydrocarbons with many different properties. Click here for some more info on polymers and plastics.
Modern technology uses large amounts of electrical power. This is normally generated at power plants which convert some other kind of energy into electrical power. Each such system has advantages and disadvantages, but many of them pose environmental concerns. The efficiency of some of these systems can be improved by cogeneration (combined heat and power) methods. Process steam can be extracted from steam turbines. Waste heat produced by thermal generating stations can be used for space heating of nearby buildings. By combining electric power production and heating, less fuel is consumed, thereby reducing the environmental effects compared with separate heat and power systems. To accurately measure a company’s environmental footprint, you must look at the impact that company’s products have on the planet. Apple uses comprehensive life cycle analysis to determine exactly where our greenhouse gas emissions — all 10.2 million metric tons of them1 — come from.

Manufacturing=38%
Transportation=5%

Product Use=53%

Recycling =1%

Facilities =3%
The use of fossil fuels for energy contributes to a number of environmental problems. As the cleanest of the fossil fuels, natural gas can be used in many ways to help reduce the emissions of pollutants into the atmosphere. Burning natural gas in the place of other fossil fuels emits fewer harmful pollutants into the atmosphere, and an increased reliance on natural gas can potentially reduce the emission of many of these most harmful pollutants.

Pollutants emitted in the United States, particularly from the combustion of fossil fuels, have led to the development of many pressing environmental problems. Natural gas, emitting fewer harmful chemicals into the atmosphere than other fossil fuels, can help to mitigate some of these environmental issues. These issues include:
Smog, Air Quality and Acid Rain

Smog and poor air quality is a pressing environmental problem, particularly for large metropolitan cities. Smog, the primary constituent of which is ground level ozone, is formed by a chemical reaction of carbon monoxide, nitrogen oxides, volatile organic compounds, and heat from sunlight. As well as creating that familiar smoggy haze commonly found surrounding large cities, particularly in the summer time, smog and ground level ozone can contribute to respiratory problems ranging from temporary discomfort to long-lasting, permanent lung damage. Pollutants contributing to smog come from a variety of sources, including vehicle emissions, smokestack emissions, paints, and solvents. Because the reaction to create smog requires heat, smog problems are the worst in the summertime.

Pollutant emissions from the industrial sector and electric utilities contribute greatly to environmental problems in the United States. The use of natural gas to power both industrial boilers and processes and the generation of electricity can significantly improve the emissions profiles for these two sectors.

Natural gas is becoming an increasingly important fuel in the generation of electricity. As well as providing an efficient, competitively priced fuel for the generation of electricity, the increased use of natural gas allows for the improvement in the emissions profile of the electric generation industry. According to the National Environmental Trust (NET) in their 2002 publication entitled 'Cleaning up Air Pollution from America's Power Plants', power plants in the U.S. account for 67 percent of sulfur dioxide emissions, 40 percent of carbon dioxide emissions, 25 percent of nitrogen oxide emissions, and 34 percent of mercury emissions. Coal fired power plants are the greatest contributors to these types of emissions. In fact, only 3 percent of sulfur dioxide emissions, 5 percent of carbon dioxide emissions, 2 percent of nitrogen oxide emissions, and 1 percent of mercury emissions come from non-coal fired power plants.

The transportation sector (particularly cars, trucks, and buses) is one of the greatest contributors to air pollution in the United States. Emissions from vehicles contribute to smog, low visibility, and various greenhouse gas emissions. According to the Department of Energy (DOE), about half of all air pollution and more than 80 percent of air pollution in cities are produced by cars and trucks in the United States.
Source: EPA
Natural gas can be used in the transportation sector to cut down on these high levels of pollution from gasoline and diesel powered cars, trucks, and buses. In fact, according to the EPA, compared to traditional vehicles, vehicles operating on compressed natural gas have reductions in carbon monoxide emissions of 90 to 97 percent, and reductions in carbon dioxide emissions of 25 percent. Nitrogen oxide emissions can be reduced by 35 to 60 percent, and other non-methane hydrocarbon emissions could be reduced by as much as 50 to 75 percent. In addition, because of the relatively simple makeup of natural gas in comparison to traditional vehicle fuels, there are fewer toxic and carcinogenic emissions from natural gas vehicles, and virtually no particulate emissions. Thus the environmentally friendly attributes of natural gas may be used in the transportation sector to reduce air pollution.
Global warming, or the 'greenhouse effect' is an environmental issue that deals with the potential for global climate change due to increased levels of atmospheric 'greenhouse gases'. There are certain gases in our atmosphere that serve to regulate the amount of heat that is kept close to the Earth's surface. Scientists theorize that an increase in these greenhouse gases will translate into increased temperatures around the globe, which would result in many disastrous environmental effects. In fact, the Intergovernmental Panel on Climate Change (IPCC) predicts in its 'Third Assessment Report' released in February 2001 that over the next 100 years, global average temperatures will rise by between 2.4 and 10.4 degrees Fahrenheit. Power Plants Contribute to the
Emission of Greenhouse Gases
Source: API
The principle greenhouse gases include water vapor, carbon dioxide, methane, nitrogen oxides, and some engineered chemicals such as cholorofluorocarbons. While most of these gases occur in the atmosphere naturally, levels have been increasing due to the widespread burning of fossil fuels by growing human populations. The reduction of greenhouse gas emissions has become a primary focus of environmental programs in countries around the world.
The need for electricity generation to be clean and safe has never been more obvious. Nor has it ever been as popularly supported.

Environmental and health consequences of electricity generation are important issues, alongside the affordability of the power which is produced.

They are usually seen as external costs - those which are quantifiable but do not appear in the utility's accounts. Hence they are not passed on to the consumer, but are borne by society at large. They include particularly the effects of air pollution on human health, crop yields and buildings, as well as occupational disease and accidents. Though they are even harder to quantify and evaluate than the others, external costs include effects on ecosystems and the impact of global warming.

Production of electricity from any form of primary energy has some environmental effect. A balanced assessment of nuclear power requires comparison of its environmental effects with those of the principal alternative, coal-fired electricity generation, as well as with other options.
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