The car crisis Essay
The car crisis
Although wood is the largest source of biomass energy, we also use corn, sugarcane wastes, and other farming byproducts. There are three ways to use biomass. It can be burned to produce heat and electricity, changed to a gas-like fuel such as methane, or changed to a liquid fuel. Liquid fuels, also called biofuels, include two forms of alcohol: ethanol and methanol. Because biomass can be changed directly into a liquid fuel, it could someday supply much of our transportation fuel needs for cars, trucks, buses, airplanes, and trains. This is very important because nearly one-third of our nation’s energy is now used for transportation.
Diesel fuel can also be replaced by biodiesel made from vegetable oils! In the United States, this fuel is now being produced from soybean oil. However, any vegetable oil-corn, cottonseed, peanut, sunflower, or canola-could be used to produce biodiesel. Researchers are also developing algae that produce oils, which can be converted to biodiesel. The most commonly used biofuel in the United States is ethanol, which is produced from corn and other grains. A blend of gasoline and ethanol is already used in cities with high air pollution. However, ethanol made from corn is currently more expensive than gasoline on a gallon-for-gallon basis.
And even if we took all the corn that could possibly be grown in the United States and used it to produce ethanol, it would not make enough ethanol to power all our cars. So, it is very important for scientists to find less expensive ways to produce ethanol from other biomass crops. Today, we have found new ways to produce ethanol from grasses, trees, bark, sawdust, paper, and farming wastes. These processes could greatly increase the use of biomass energy in the United States. Imagine a new type of farm where energy crops, such as fast-growing trees or grasses, might be grown and harvested for their energy content!
Of course, like many resources, we need to manage our use of biomass or we might consume it faster than we produce it. Also, like any fuel, biomass creates some pollutants when it is burned or converted into energy. Hydropower The water in rivers and streams can be captured and turned into hydropower, also called hydroelectric power. The most common form of hydropower uses dams on rivers to create large reservoirs of water. Water released from the reservoirs flows through turbines, causing them to spin. The turbines are connected to generators that produce electricity.
Hydroelectric power plants in the United States generate enough electricity to power whole towns, cities, and even entire regions of the country. Hydropower currently is one of the largest sources of renewable power, generating about 10 percent of the United States’ electricity. Hydropower is also inexpensive, and like many other renewable energy sources, it does not produce air pollution. However, the drawback to hydropower is that damming rivers can change the ecology of the region. For example, the water below the dam is often colder than what would normally flow down the river, so fish sometimes die.
The water level of the river below the dam can be higher or lower than its natural state, which affects the plants that grow along the riverbanks. Energy from trash What you may throw out in your garbage today just might become fuel for someone else. That’s right, whether you call it trash or garbage, this municipal solid waste has the potential to be a large energy source. In 1993, the Environmental Protection Agency estimated that the United States generated 207 million tons (188 million metric tons) of trash. Out of all that trash, however, only 32 million tons (29 million metric tons) were converted to energy.
Garbage is also an inexpensive energy resource. Unlike most other energy resources, someone will collect garbage, deliver it to the power plant, and pay to get rid of it. This helps cover the cost of turning the garbage into energy. Garbage is also a unique resource because we all contribute to it. Municipal solid waste can be burned in large power plants to generate electric power. Municipal waste-to-energy plants currently generate about 2500 megawatts of electricity-the equivalent of several large coal plants. There is also a way to use the energy trapped in landfill garbage.
When food scraps and other wastes decay, a gas called methane is produced. Methane is the main ingredient in natural gas. We can drill wells into landfills to release this gas. Pipes from each well carry the methane gas to a central point where it is cleaned. The gas can then be burned to produce steam in a boiler, or it can be used to power generators to produce electricity. However, as with burning any type of fuel, municipal solid wastes can produce air pollution when they are burned and turned into energy. Renewable energy in your future One day, your entire home’s energy may come from the sun or the wind.
You may not think twice about filling your car’s gas tank with biofuel. And your garbage might contribute to your city’s energy supply. As scientists push the limits of renewable energy technologies and improve the efficiencies and costs of today’s systems, we will soon be to the point when we may no longer rely mostly on fossil fuel energy. Suhail Razaq 11G Show preview only The above preview is unformatted text This student written piece of work is one of many that can be found in our GCSE Electricity and Magnetism section.
Subject: United States,
University/College: University of California
Type of paper: Thesis/Dissertation Chapter
Date: 17 October 2017
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