Gas fired power plants
Power stations using gas have a much smaller carbon footprint than that of coal. Moreover, the gas is piped straight to the power stations, lowering secondary carbon emissions because no transportation is involved in its delivery.
Electricity generated by gas today gives about 360g C0 2/kWh (0.88 pounds of C0 2 per kWh) carbon footprint, while previous gas power stations which used “open cycle” technology gave about 479g C0 2/kWh carbon footprint, or 1 pound of C0 2 per kWh.
Oil fired power stations are small sized stations that are used to help “top up” electricity during high peaks or demand. But large power stations that use oil are also available in the U.S. to generate electricity. These give less pollution than power stations that use coal, although they are still less clean than gas powered stations; more nitrogen oxide is generated with gas than by coal. This result is of great concern, as nitrogen oxide has a serious impact on greenhouse gas.
Nuclear power stations
There is little air pollution from nuclear power stations. However, the radioactive waste that is generated must be handled securely.
Energy is generated consistently by nuclear power stations, which act as the power grid’s “base load.” This in turn is supplemented by coal and gas fired power stations when there is a demand. France is currently using nuclear power stations for generating most of their electricity needs, and a lot of nations utilize nuclear power stations in their current power mix.
Geo-thermal power stations
Geo-thermal energy comes from extracting the heat that is found deep in the earth, a process that is accomplished by drilling boreholes and pumping water. The heat generates steam to turn the turbines, which then generates electricity.
Geo-thermal energy comes very cheaply and easily in areas that have numerous volcanoes as well as hot water surface pools; the reason why in winter some street pavements in major cities are heated. Iceland has used their geographical proximity to the tectonic plates found in the earth's surface to their advantage by pioneering electrical generation by use of geo-thermal energy. Geo-thermal energy supplies 30 percent of the electricity used in Iceland, while meeting the heating and hot water needs in about 90 percent of the country’s buildings.
Today, many geo-thermal power stations have been built in various countries, including the U.S., which is home to the largest group of geothermal plants in the world (The Geysers in the state of California), the U.K. and in Canada for testing.
Geo-thermal power emits about 122g C0 2/kWh carbon or about 4Y2oz of C0 2 per kWh. As with natural gas, there are concerns about the impact geothermal energy has on the environment, since the fluid that is drawn from deep within the earth also releases methane, hydrogen sulphide, ammonia, mercury and arsenic. Modern plants are equipped with emission control systems that capture and filtered these emissions, reducing the exhaust and further reducing any negative environmental impacts.