Renewable Energy

Several opportunities exist to substantially improve the efficiency of how we generate and distribute electricity and thermal energy. The technology used in combined heat and power (CHP)/district energy systems is well established, while the smart grid is a cutting edge application of information and communication technologies. These highly efficient generation and distribution systems reduce our total energy use while providing the same amount of heat and power to the end user. This means fewer greenhouse gases and other air and water pollutants produced by fossil fuel combustion, enhanced energy security by reducing peak load demand, and overall cost savings.

Combined Heat and Power
Combined heat and power (CHP), also known as cogeneration, is the simultaneous production of electricity and heat from a single fuel source. Approximately two-thirds of the energy used to create electricity in conventional thermal power plants is lost in the conversion process. CHP is a system that reclaims some of this lost energy by using the "waste" heat to provide heating to the power plant facility or to buildings that are connected to the power plant by a steam pipe network known as district energy. CHP increases the energy efficiency of power generation to up to 90 percent and is best suited for urban areas, industrial parks, college campuses, military bases and other communities that are close enough to their power Renewable resources such as biomass, water, wind, solar, and geothermal provide clean alternatives to the fossil fuels that cause climate change. According to the Energy Information Administration, renewable resources supplied 8 percent of total U.S. energy (including electricity, thermal energy, and transportation fuels) in 2011. Biomass generated 48 percent of U.S. renewable energy, and it is the only renewable resource that can be transformed into liquid transportation fuels (although the electrification of the transportation sector will allow power generated from other renewable resources to "fuel" our vehicles). Hydropower provided 35 percent of U.S. renewable energy, followed by wind at 13 percent. Other technologies, including geothermal and solar power, made up the remaining 4 percent. Renewable energy has the largest impact on our environmental, security, and economic objectives when it is paired with aggressive energy efficiency strategies to reduce overall demand.

Biomass Energy
Biomass (plant or animal material) can be used to produce electricity, thermal energy, or transportation fuels. Every region has its own locally generated biomass feedstocks from agriculture, forest, and urban sources.

Hydropower and Other Water Technologies
Water 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 in the United States, there are many opportunities to expand energy production at dams without turbines and by using newer technologies in both rivers and oceans.

Wind energy can be used to generate electricity for utilities or individual buildings. The best U.S. resources for utility scale wind farms are in the Midwest, Texas and the West, as well as offshore sites in the Great Lakes and off the Atlantic Coast.

Geothermal energy, or the heat below the earth's surface, can be used for electricity or thermal energy. Geothermal power plants require stronger resources that, in the United States, are primarily located in the West. Geothermal heat pumps, which heat and cool buildings, are effective in all regions.

Solar energy systems use the sun's rays for electricity or thermal energy. In the United States, utility scale solar power plants are located primarily in the Southwest. However, smaller scale rooftop photovoltaic cells and hot water systems are effective in all regions.

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