Electricity is produced by converting energy from one form to electricity. The process used may be a direct conversion process, where the energy source is converted directly to electricity. An example of this is solar photovoltaic cells, which converts the energy found in solar radiation directly to electricity. An indirect conversion process consists of converting energy from one form, to an intermediate form, to electricity. Coal-fired generating plants are an example of the indirect process, as the chemical energy released as heat by burning the coal is changed to rotating kinetic energy by the steam turbine, and then the rotating kinetic energy is converted to electricity. The majority of the electricity today is produced through an indirect energy conversion process. Both indirect and direct processes use the following major sources of energy for the production of electricity: fossil fuels, nuclear energy, solar radiation, and hydro energy.
Fossil fuels include coal, petroleum, and natural gas. Fossil fuels are a finite, non-renewable resource. They remain the primary source for the production of electricity. The combustion of these fuels releases their chemical energy, which produces heat to power steam turbines. The steam turbines power rotating electric generators, which turn kinetic energy into electricity. No energy conversion process converts all the energy present in one form completely into the new form. Since the production of electricity from fossil fuels involves several energy conversion steps fossil fuel power plants inefficiently produce power
Energy can take on many different forms. A pitched baseball has kinetic energy, or energy of motion. When the ball is high above the ground, we say it has gravitational energy. Stretching a rubber band is an example of stored elastic energy. Corn flakes and gasoline store chemical energy, while uranium and plutonium store nuclear energy. A hot potato contains more thermal energy than it did when it was cold. Electrical energy is transmitted along wires from power plants to appliances, and radiant energy is given off by light bulbs, lasers, stovetops, and stars.
When they were first discovered they were plentiful and relatively easy to extract, they were profitable and dramatically impacted our ability to have comfort and travel as well as increase work capacity. Now years later they are harder to extract, our supply is dwindling, and the pollution is negatively impacting our quality of life, but we are addicted. We don't need to use as much as we do, but the one thing that hasn't changed is the profitability. Dirty energy companies like oil and coal are spending billions of the dollars we have paid for the energy to keep us addicted, they spend millions each year on marketing false hopes, like clean coal and misinformation campaigns, like the one I saw with nurse saying why should only rich people be comfortable, I deserve it too. The spend millions on campaigns to get candidates elected then toss all kinds of perks there way when the lobbyists come calling to sway there vote. The oil companies get millions if not billions is tax credits, and usually aren't responsible for clean up when things go wrong, that again is left to the tax payers. If you took into account all the taxes we pay to support the most profitable corporations on the planet we would be paying well over $10 per gallon.
Wind power is the harnessing of wind through turbines to create electricity. America currently is the leader in wind power. Globally, the long-term technical potential of wind energy is believed to be able to supply alone the current global energy demand. Wind power, as an alternative to fossil fuels, is plentiful, renewable, widely distributed, clean, produces no greenhouse gas emissions during operation and uses little land compared to solar power plants. The overall cost per unit of energy produced is similar to the cost for new coal and natural gas installations. Wind power is a popular form of energy generation; however, the construction of wind farms is not globally welcomed. The problem with this type of power is that turbines destroy natural scenic views and generate noise pollution.
Hydroelectricity is power derived from the energy of failing water which can be harnessed and used. Since water is about 800 times denser than air, even a slow flowing stream of water, can yield considerable amounts of energy. Once a hydro power plant is constructed, the project produces no direct waste. However, the number of water sources limits the development of hydroelectric power stations, which is why underwater tide turbines within the oceans may be another great alternative power source to harness power from the natural flow of water.
Fossil fuels are currently pretty cheap, as are the methods of generating energy from them. With our existing distribution networks, we can get fossil fuels of all kinds all over the world. That makes it easy to use them, no matter where you are. Many alternative fuels remain expensive, hard to distribute, difficult to get energy from and hard to access, making the switch over extremely difficult. Power stations that make use of fossil fuel can be constructed in almost any location. This is possible as long as large quantities of fuel can be easily brought to the power plants. Transporting oil and gas to the power stations can be made through the use of pipes making it an easy task. When coal is used in power plants, they are very cost effective. Coal is also in abundant supply. A major advantage of fossil fuels is their capacity to generate huge amounts of electricity in just a single location.
Environmentally, the mining of coal results in the destruction of wide areas of land. Mining this fossil fuel is also difficult and may endanger the lives of miners. Coal mining is considered one of the most dangerous jobs in the world. Power stations that utilize coal need large amounts of fuel. In other words, they not only need truckloads but trainloads of coal on a regular basis to continue operating and generating electricity. This only means that coal-fired power plants should have reserves of coal in a large area near the plants location. Use of natural gas can cause unpleasant odors and some problems especially with transportation. Use of crude oil causes pollution and poses environmental hazards such as oil spills when oil tankers, for instance, experience leaks or drown deep under the sea. Crude oil contains toxic chemicals which cause air pollutants when combusted. Coal also produces carbon dioxide when burned compared to burning oil or gas. Additionally, it gives off sulphur dioxide, a kind of gas that creates acid rain. Pollution is a major disadvantage of fossil fuels. This is because they give off carbon dioxide when burned thereby causing a greenhouse effect. This is also the main contributory factor to the global warming experienced by the earth today.