Alternative Energy Sources, also referred to as renewable resources are ways of delivering power with minimal impact on the environment. These sources are typically more green/clean than traditional “fossil fuel” methods such as oil or coal, but their true value lies in the fact that they are inexhaustible.
o Solar energy is a locally available renewable resource. It does not need to be imported from other regions of the country or from across the world, which reduces our dependence on imported resources.
o Electricity produced by solar is clean and silent. Solar energy does not release any harmful air or water pollution into the environment, deplete natural resources, or endanger animal or human health.
o A one kilowatt solar system will prevent approximately 170 lbs. of coal from being burned, 300 lbs of CO2 from being released into the atmosphere and 105 gallons of water from being consumed each month!
o Electricity generated by a solar system can be used to offset your energy consumption, resulting in lower monthly power bills. Using solar PV power helps the community by reducing electricity demand and by providing electricity for the grid when you generate more than you use during the day, when the demand is highest.
o The U.S. Department of Energy lists three types of solar technologies: concentrating solar power, photovoltaics, and solar heat. Concentrating solar power systems use reflective materials that concentrate the sun’s heat energy to drive a generator that produces electricity. Photovoltaic systems use semiconductor materials that convert sunlight directly to electricity. Solar heating consists of solar collectors that absorb the sun’s energy to provide low-temperature heat used directly for hot water or space for buildings.
o According to the U.S. Department of Energy, wind has been the fastest growing source of electricity generation in the world through the 1990s.
o With largely untapped wind energy resources throughout the country and declining wind energy costs, the United States is now moving forward into the 21st century with an aggressive initiative to accelerate the progress of wind technology and further reduce its costs, to create new jobs, and to improve environmental quality.
o Almost everywhere, the shallow ground or upper 10 feet of the Earth’s surface maintains a nearly constant temperature between 50° and 60°F (10° and 16°C). Geothermal heat pumps can tap into this resource to heat and cool buildings. A geothermal heat pump system consists of a heat pump, an air delivery system (ductwork), and a heat exchanger-a system of pipes buried in the shallow ground near the building. In the winter, the heat pump removes heat from the heat exchanger and pumps it into the indoor air delivery system. In the summer, the process is reversed, and the heat pump moves heat from the indoor air into the heat exchanger. The heat removed from the indoor air during the summer can also be used to provide a free source of hot water.
· Cogeneration (CHP)
o Combined heat and power (CHP), also known as cogeneration, is an efficient, clean, and reliable approach to generating power and thermal energy from a single fuel source. Commercial CHP systems can provide significant financial savings on fuel costs used to provide electricity and heat. Producing your own electricity on-site has significant advantages. CHP systems have economic and environmental benefits including reduced energy costs, offset of capital costs, protected revenue streams, hedge against volatile energy prices, and reduced reliance on outside energy sources. CHP technologiesinclude turbines, micro-turbines, internal combustion/reciprocating engines, steam engines/turbines, and fuel cells.
o Utilizing the local natural gas supply network gas engine-based cogeneration systems provide a stable supply of electrical power that, if needed, can be isolated from the local electricity grid. The heat produced by the engine can be recovered either as hot water or as steam for use by surrounding operations. In addition, if there is a local need for cooling power, the heat can be fed into an absorption chiller providing a source of cold water. This cold water can in turn be used to support a refrigeration or air conditioning system. Systems providing electricity, heat and cooling are called tri-generation plants.
o Natural gas has the lowest levels of carbon dioxide production and is the cleanest of all the fossil fuels. Gas engines generate electricity at high efficiency making the greatest use of the fuel source. The utilization of cogeneration for embedded generation helps minimize losses of electricity associated with its transmission from centralized power plants.
Hydropower relies on the gravitational force of flowing water, usually from a dammed body of water, to spin a turbine and generate electricity. In addition to the low Co2 output, hydropower is consistent and efficient. Hydropower has become the most-used form of renewable energy, accounting for approximately 20 percent of the world’s electricity in 2006; hydro has no carbon emissions, and is both renewable and sustainable.