Renewable Energy to Renew the World
Sources of renewable energy include biomass, solar, wind, hydro and geothermal energy. Renewable energy is constant and is self-replenishing. It is also cleaner and more friendly to the environment. Renewable energy sources have made a huge impact in decreasing emission of carbon dioxide (CO2) into the Earth’s atmosphere. It is expected that renewable energy sources, especially wind energy, small hydro electrid power stations, biomass energy and solar energy will become economically competitive to conventional energy sources in the future, however they are not expected to overtake fossil fuels in keeping up with the global energy demand due to the fact that renewables have limitations.
Sun radiation is major contributor to energy sources. Solar technology uses the sun’s energy to provide heat, light, hot water, electricity and also for cooling homes, business and industries. Solar power is expanding as technology advances and cost becomes more competitive. These methods use photovoltaic systems, passive solar heating and solar process heat and space cooling.
Using the wind as a source of energy provides a clean, inexhaustible way to generate enough electricity to power millions of people. Wind power is the world’s fastest growing source of energy after solar. The United States can currently generate more than 10,000 megawatts (MW) of electricity from the wind, which is enough to power 2.5 million average American homes. Industry experts estimate that, with proper refinement and development, wind energy could provide 20% of the U.S. energy needs.
Biomass energy uses plant matter like trees, grasses, agricultural crops or other biological material. This can be used as a solid fuel, or converted into liquid or gaseous forms, for the production of electric power, heat, chemicals, or fuels. By incorporating a diversity of biomass conversion processes, all of these products can be made in one facility, which is called a biorefinery. This technology will provide a cost effective, environmentally friendly way of obtaining energy, and will decrease the dependence on foreign oil, improve air quality and support rural economies.
Geothermal energy, which derives heat from the earth’s inner core, is meeting a vast portion of electrical power demand in several developing countries. Approximately 8,000 megawatts of geothermal electricity is now being produced globally. To use geothermal energy, several new technologies have been developed to produce electricity from hydrothermal (hot water/steam) resources. In the future, it might be possible to use the heat of the deep, hot, dry rock formations of Earth’s crust, and possibly the even the deeper and nearly unlimited energy in the Earth’s magma. There are two basic types of geothermal power plants used today: Steam and binary. The steam plants use very hot (more than 300° F) steam and hot water resources. The steam then turns turbines, which drive generators that generate electricity. The only significant emission from these plants is steam (water vapor). Minute amounts of carbon dioxide, nitric oxide, and sulfur are emitted, but are nearly 50 times less than the traditional fossil-fuel power plants. Energy produced this way currently costs about 4-6 cents per kWh. Binary plants use lower temperature, but much more common, hot water resources (100° F – 300° F). The hot water is passed through a heat exchanger in conjunction with a secondary fluid with a lower boiling point. The secondary fluid vaporizes, which turns the turbines, which drive the generators. The remaining secondary fluid is simply recycled through the heat exchanger. With binary plants nothing is emitted. Energy produced by binary plants currently costs about 5 to 8 cents per kWh.
In the future, the use of renewable energy will significantly increase because the number of non-renewable energy supplies will diminish over time, as well as the desire to provide a less damaging effect on the environment.
Defining the Different Types of Water Power
Using water to harness power is a tradition, which goes back over two thousand years ago when the Greeks learned how to turn massive wheels to rotate shafts for their wheat flour grinders. In the 18th century, there were literally thousands of communities around the world that used water energy (hydro energy). Hydro power uses the form of falling water by gravity to produce useful energy. The falling water is directed through a turbine, causing it to spin. The spinning turbine is connected to a generator, which produces energy. Small-scale hydro systems have several advantages. The generation process produces no pollution. It doesn’t require a large dam or reservoir; some systems can be powered by only a small stream so that a little bit of water goes a long way. More recently, many people have been using water on a smaller scale to generate electricity without the problems and costs involved with fossil fuels or large dams. Small-scale water power is one of the most environmentally sound and friendly ways to produce electricity.
In today’s world, there are small hydropower projects are in place in remote communities such as India, China, Peru and Nepal, Malaysia, Vietnam, and also in highly industrialized counties including the United States. This type of hydro power offers an emissions-free solution. Hydro power systems take the energy in flowing water to make electricity.
Hydro energy is a significant renewable energy source, competitive to fossil fuels and nuclear energy. In approximately the last thirty years, the production of energy in water power plants has tripled. Nuclear power plants have, in that same period, almost hundred times more production growth, due to restrictions that hydro energy has. It can not be used in all locations due to the need of an abundance of fast flowing water, and the need to have the power to last throughout the year. To negate effect of water level’s fluctuation, water gates, as well as accumulation lakes are built, which significantly increases whole power plant’s expenditures, and also raises the level of underground waters near the accumulation. Underground water level has a large influence on flora and fauna, so hydro-energy isn’t completely harmless for environment. It is estimated that only about 25% of world’s hydro energetic potential is used. Most of the unused potential is located in the under developed countries.
There are three main kinds of hydro electrics: Fluid, accumulative (hydro electric dam), and the reversible (pumped-storage plants) hydro electric. By explanation, fluid hydro electrics are the ones that do not have upstream accumulation or its accumulation can be emptied for less than two hours with nominal power. This means that almost direct use of kinetic energy of the water is used for the turbine’s movement. These hydro electrics are the simplest to construct, but are very dependant upon the fluidity of the water. With hydro electric dams the critical parts are accumulation, dam, clench, gravity intake, water chamber, rail chamber, pressure pipelines, engine room and water vent. There are two types of hydro electric dams: Near the dam and derivational. Near the dam is located under the dam itself, and derivational is located much more below the dam with pipelines as connectors to accumulation. Hydro electric dams are the most often used source of gaining electricity from water’s energy. Problems occur during the summer months, when natural flow gets too small for hydro electric’s functioning. In that case, the dam must be sealed and it is necessary to at least maintain water level, which is biological minimum. A problem can arise when the underground water level decreases, but the growing desire for renewable fuel, as well as the concern for a cleaner environment, makes the performance of hydro power an exceptional solution for solving energy needs.