Natural Gas Power Plant Natural Gas example essay topic

Natural Gas Power Plant Natural gas is a fossil fuel that is created when decomposed plants and animals are subjected to intense heat and pressure within the earth over thousands of years. It is the carbon content in natural gas that is combusted to generate electric power. Since humans consume natural gas at a significantly higher rate than it is naturally produced natural gas is considered a nonrenewable energy source. A typical natural gas power plant is shown in Figure 1.

Figure 1: Natural gas power plant. The electric power from a natural gas power plant is generated using a similar combustion process as oil and coal fired power plants. These fossil fuel based power plants use steam driven turbines and generators to produce electric power. The University of Washington uses a natural gas power plant with a diesel powered back-up system.

The general process of electric power production using a natural gas power plant is now described. The natural gas is transported to the power plant through a pipeline or drawn from a tank. The natural gas is then fed into a natural gas fired turbine where combustion takes place. The combusted gas is combined with air form an outside air intake then pushed into a heat recovery steam generator. The hot exhaust is used to heat treated water to form pressurized steam. This pressurized steam is then forced through a steam turbine, which is connected to an electric generator.

The generator produces the electric power that is then boosted using a transformer. The pressurized steam then passes through a condenser where it is turned into hot water. The hot water is cooled in the cooling towers and is then recycled back into a storage tank or is discharged. Pollution is expelled from the heat recovery steam generator. The most abundant component of pollution from natural gas combustion is carbon dioxide. More discussion on the environmental impacts of natural gas power plants compared to oil and coal fired power plants is presented in the next section.

Environmental Aspects With the greenhouse effect being a major concern in today's society, many cities have recently turned to utilizing natural gas power plants to reduce emissions because of the sulphur dioxide, nitrogen oxides and greenhouse gases these plants produce are 99.5%, 95% and 60% lower, respectively, than those of a coal-fired power plant, while still maintaining zero emissions of mercury, lead and cancer causing pollutants. Natural gas is 80 to 95% methane. Methane is a global warming gas 20 times worse than CO 2 (Carbon Dioxide) at trapping heat in the atmosphere. Because natural gas combustion emits less CO 2 than either coal or oil, its advocates argue that it can mitigate global warming if used as a replacement fuel for transportation and electrical generation. (The New England Gas Association. "Natural Gas and Power Generation") Natural Gas (Ontario Clean Air Alliance "Going Gree: A Consumers Guide to Choosing Cleaner Electricity".

Online posting. web Coal plants are the single largest industrial contributors to this crisis. Coal plants are major producers of: Nitrogen oxides, which combine with other pollutants to form ground-level ozone, one of the most noxious parts of the smog brew. Sulphur dioxide, which contributes to the yellow haze that hangs over Southern Ontario and is a major factor in causing acid-rain damage to our lakes, rivers and forests. Mercury, which can in even tiny amounts have a devastating impact on the human nervous system, especially for children and the unborn.

Exposure to mercury can cause brain and kidney damage and even death. Mercury exposure has also been linked to impairment of children's reasoning skills. Lead, which is also particularly harmful to children and can cause brain damage, impair growth, damage kidneys and cause learning and behavioral problems. Heavy metals, including cadmium and chromium, which are known cancer-causing toxins. U.S. Environmental Protection Agency. "Electricity from Natural Gas". Online posting.

AES Calgary ULC. "Technical FAQ's" (Image of Figure 1 taken from here and modified. ).