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Fossil fuels and Renewable fuelsFossil fuels, including coal, oil and natural gas, are currently the world's primary energy source. Formed from organic material over the course of millions of years, fossil fuels have fueled global economic development over the past century.OilOil is the world’s primary fuel source for transportation. Most oil is pumped out of underground reservoirs, but it can also be found imbedded in shale and tar sands. Once extracted, crude oil is processed in oil refineries to create fuel oil, gasoline, liquefied petroleum gas, and other nonfuel products such as pesticides, fertilizers, pharmaceuticals, and plastics. Top exporters of the world include Canada, Mexico, Saudi Arabia, Katar, Russia, Venezuela, and Nigeria Etc. Heavier crude oils, especially those extracted from tar sands and shale, require the use of energy intensive methods that result in more emissions and environmental degradation compared to conventional oil. As conventional oil from underground reservoirs runs out, more oil producers are turning to unconventional sources such as tar sands and oil shale.CoalCoal is primarily used to generate electricity and is responsible in main for 42 percent of the electric power supply. China is the global leader in coal production, responsible for almost 50 percent of world supply.Natural GasNatural gas comprised about 22 percent energy use in 2010 and is most commonly used to produce heat or electricity for buildings or industrial processes. Less than two percent of natural gas is used as a transportation fuel, typically for bus fleets. Natural gas is also used to produce fertilizer, paints, and plastics. Natural gas is most commonly transported by pipeline, which makes Canada the key exporter to the United States, while Russia remains the main supplier for much of Europe. Increasingly, however, natural gas is being transported by ship in a liquefied form (LNG) to meet greater global demand for the fuel. Natural gas burns cleaner than coal and oil, with almost zero sulfur dioxide emissions and far fewer nitrogen oxide and particulate emissions. Natural gas releases almost 30 percent less carbon dioxide than oil and 43 percent less than coal.Fossil Fuel AlternativesThere are several alternative resources that can supply clean, renewable energy to replace fossil fuels, including water, biomass, wind, geothermal, and solar energy. Renewable energy is derived from resources that are replenished naturally on a human timescale. Such resources include biomass, geothermal heat, sunlight, water, and wind. All of these sources have their strengths and weaknesses. Some are more suited to certain locations that others, for instance. Some only produce electricity intermittently (when the sun is shining in the case of solar), though they can be paired with energy storage solutions to provide reliable electricity 24 hours a day throughout the year. Others, such as biomass, hydropower, and geothermal, can be used as baseload generation, producing a constant, predictable supply of electricity. None of these sources can meet all of our electricity needs effectively. But, together, they can completely displace fossil fuels without increasing the cost of electricity.Bioenergy (biofuels and biomass)Biomass (plant or animal material) can be used to produce electricity, thermal energy, or transportation fuels.Hydrogen Fuel CellsHydrogen fuel cells are a clean, reliable, quiet, and efficient source of high-quality electric power. They use hydrogen as a fuel to drive an electrochemical process that produces electricity, with water and heat as the only by-products.Hydropower and Other Water TechnologiesWater technologies can be used for electricity or thermal energy all across the country. Although there are few, if any, appropriate sites left to build large dams, there are many opportunities to expand energy production at dams without turbines and by using newer technologies in both rivers and oceans.WindWind energy can be used to generate electricity for utilities or individual buildings.GeothermalGeothermal energy, or the heat below the earth's surface, can be used for electricity or thermal energy. Geothermal heat pumps, which heat and cool buildings, are effective in all regions. Geothermal power plants, however, require more active geothermal sources.SolarSolar energy systems use the sun's rays for electricity or thermal energy. Smaller scale rooftop photovoltaic cells and hot water systems are effective in all regions. |
