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Fossil fuels—coal, oil, and natural gas—are America's primary source of energy, accounting for 85 percent of current US fuel use.

Many of the environmental problems our country faces today result from our fossil fuel dependence. These impacts include global warming, air quality deterioration, oil spills, and acid rain.

Over the last 150 years, burning fossil fuels has resulted in more than a 25 percent increase in the amount of carbon dioxide in our atmosphere.

It development of technology have been well proven over the years of time. When the sun emit heat to warm of the Earth it would be unbearable without wind. Wind widely disperses the heat making it bearable for all living things to survive. Without wind nothing would exist, it would just like all the other planets uninhibited by human nature or any living things for that matter.

A wind turbine is a machine that transforms kinetic energy from the wind into mechanical energy.

Wind power was first used in ancient times with the sail boat.

Challenges Wind power must compete with conventional generation sources on a cost basis. Depending on how energetic a wind site is, the wind farm may or may not be cost competitive. Even though the cost of wind power has decreased dramatically in the past 10 years, the technology requires a higher initial investment than fossil-fueled generators. Good wind sites are often located in remote locations, far from cities where the electricity is needed. Transmission lines must be built to bring the electricity from the wind farm to the city. Wind resource development may compete with other uses for the land and those alternative uses may be more highly valued than electricity generation. Although wind power plants have relatively little impact on the environment compared to other conventional power plants, there is some concern over the noise produced by the rotor blades, aesthetic (visual) impacts, and sometimes birds have been killed by flying into the rotors. Most of these problems have been resolved or greatly reduced through technological development or by properly siting wind plants.

Geothermal energy has been used for thousands of years in some countries for cooking and heating.

How it works

Hot rocks underground heat water to produce steam. We drill holes down to the hot region, steam comes up, is purified and used to drive turbines, which drive electric generators.

Big cities need large amounts of electricity to function. Often, this is transported from generating sites located in remote areas hundreds or even thousands of kilometers away. The question is how to move as much electricity as possible from renewable generation sites like hydro plants and wind parks without impairing the function of the power networks that need it.

One of the challenges of renewable power generation like wind and solar power is that it can be interrupted, and this variability affects the stability of the power produced

The "smart grid" will create a power network that is more reliable, flexible, secure and efficient

Method Cents/kW-h Limitations and Externalities WindCurrently supplies approximately 1.4% of the global electricity demand. Wind is considered to be about 30% reliable. 4.0 - 6.0 Cents/kW-h Wind is currently the only cost-effective alternative energy method, but has a number of problems. Wind farms are highly subject to lightning strikes, have high mechanical fatigue failure, are limited in size by hub stress, do not function well, if at all, under conditions of heavy rain, icing conditions or very cold climates, and are noisy and cannot be insulated for sound reduction due to their size and subsequent loss of wind velocity and power. GeothermalCurrently supplies approximately 0.23% of the global electricity demand. Geothermal is considered 90-95% reliable. 4.5 - 30 Cents/kW-h New low temperature conversion of heat to electricity is likely to make geothermal substantially more plausible (more shallow drilling possible) and less expensive. Generally, the bigger the plant, the less the cost and cost also depends upon the depth to be drilled and the temperature at the depth. The higher the temperature, the lower the cost per kwh. Cost may also be affect by where the drilling is to take place as concerns distance from the grid and another factor may be the permeability of the rock. HydroCurrently supplies around 19.9% of the global electricity demand. Hydro is considered to be 60% reliable. 5.1 - 11.3 Cents/kW-h Hydro is currently the only source of renewable energy making substantive contributions to global energy demand. Hydro plants, however, can (obviously) only be built in a limited number of places, and can significantly damage aquatic ecosystems. SolarCurrently supplies approximately 0.8% of the global electricity demand. 15 - 30 Cents/kW-h Solar power has been expensive, but soon is expected to drop to as low as 3.5 cents/kW-h. Once the silicon shortage is remedied through alternative materials, a solar energy revolution is expected.

Tide 2 - 5 Cents/kW-h Blue Energy's tidal fence, engineered and ready for implementation, would provide a land bridge (road) while also generating electricity. Environmental impact is low. Tides are highly predictable.

Method Cents/kW-h Limitations and Externalities GasCurrently supplies around 15% of the global electricity demand. 3.9 - 4.4 Cents/kW-h Gas-fired plants and generally quicker and less expensive to build than coal or nuclear, but a relatively high percentage of the cost/KWh is derived from the cost of the fuel. Due to the current (and projected future) upwards trend in gas prices, there is uncertainty around the cost / KWh over the lifetime of plants. Gas burns more cleanly than coal, but the gas itself (largely methane) is a potent greenhouse gas. Some energy conversions to calculate your cost of natural gas per kwh. 100 cubic feet (CCF)~ 1 Therm = 100,000 btu ~ 29.3 kwh. CoalCurrently supplies around 38% of the global electricity demand. 4.8 - 5.5 Cents/kW-h Increasingly difficult to build new coal plants in the developed world, due to environmental requirements governing the plants. Growing concern about coal fired plants in the developing world (China, for instance, imposes less environmental overhead, and has large supplies of high sulphur content coal). The supply of coal is plentiful, but the coal generation method is perceived to make a larger contribution to air pollution than the rest of the methods combined.

Another benefit of condition monitoring is that it allows condition-based maintenance. Instead of replacing components after fixed time intervals based on empirical values, they can be replaced only when required, such as when signs of wear are detected.

Unlike fossil fuel power plants, no smoke is emitted from geothermal power plants, because no burning takes place; only steam is emitted from geothermal facilities. Emissions of nitrous oxide, hydrogen sulfide, sulfur dioxide, particulate matter, and carbon dioxide are extremely low, especially when compared to fossil fuel emissions. The binary geothermal plant, which currently represents around 15% of all geothermal plant capacity, along with the flash/binary plant, produce nearly zero air emissions. Even dry steam plants, which are considered to have the highest levels of air emissions, are considered environmentally benign compared with fossil fuels. For example, Lake County, California, downwind of The Geysers, has met all federal and state ambient air quality standards for almost 25 years. There are 21 power plants at The Geysers, comprising a significant complex of electric generation facilities, yet even despite this, air quality is excellent. At The Geysers, air quality has even improved as a result of geothermal development because hydrogen sulfide, which would ordinarily be released naturally into the atmosphere by hot springs and fumaroles, instead now passes through an abatement system that reduces hydrogen sulfide emissions by 99.9%. (1) See also Myth #2.

Solar Energy comes from Sun.

The terms 'wind energy' describe the procedure by which wind is employed to produce mechanical power or electricity.

When we get electricity from renewable energy sources like wind and solar power, we avoid the carbon dioxide emissions that would have come from burning fossil fuels like coal, oil, or natural gas.

Motions in nature, for example ocean waves, can play a significant role in tomorrow's electricity production, but the constructions require adaptations to its media. Engineers planning hydropower plants have always taken natural conditions, such as fall height, speed of flow, and geometry, as basic design parameters and constraints in the design

Extensive simulations of the wave energy concept are presented, along with results from the experimental setup of a multisided permanent magnet linear generator. The prototype is designed through systematic electromagnetic field calculations. The experimental results are used for the verification of measurements in the design process of future full-scale direct wave energy converters. The present paper, describes the energy conversion concept from a system perspective, and also discusses the economical and some environmental considerations for the project.

Waves are generated by low pressure weather systems sometimes thousands of miles from where they will break on the shore. Waves are born from high winds pushing the surface of the ocean

Let’s not hide the fact that manufacturing solar panels requires resources, fossil fuels that release CO2 emissions and add to our carbon footprint. However, it’s been shown in numerous studies that solar panel production releases nowhere near as much CO2 and other greenhouse gases as electric generated from coal, oil, natural gas, etc. (And you still need to produce the equipment to generate electricity from those sources as well.)

rather than burning hydrogen in place of gasoline as BMW has done with its internal combustion hydrogen cars. Either way, the only emission is water vapor.

They were formed from prehistoric plants and animals that lived hundreds of millions of years ago.

Some coal deposits, however, were formed from freshwater swamps which had very little sulfur in them. These coal deposits, located largely in the western part of the United States, have much less sulfur in them

A wind turbine gathers energy from the wind through the mechanical rotation of its blades. This is mechanically generated energy from kinetic energy that is then turned into electrical energy.

Waves are caused by the wind blowing over the surface of the ocean

. Ocean waves contain tremendous energy potential. Wave power devices extract energy from the surface motion of ocean waves or from pressure fluctuations below the surface.  

What is U.S. electricity generation by energy source? In 2012, the United States generated about 4,054 billion kilowatthours of electricity.  About 68% of the electricity generated was from fossil fuel (coal, natural gas, and petroleum), with 37% attributed from coal. Energy sources and percent share of  total electricity generation in 2012 were:  Coal 37% Natural Gas 30% Nuclear 19% Hydropower 7% Other Renewable 5% Biomass 1.42% Geothermal 0.41% Solar 0.11% Wind 3.46% Petroleum 1% Other Gases < 1%

Somewhat surprisingly, the hot air that carries the heat from the earth at geothermal sites also contains carbon dioxide, CO2, the Greenhouse Gas that sends anti-technologists into a frenzy.  The suite of 20 geothermal sites from which Southern California Electric is obligated to buy electricity produces 730 tonnes of CO2 for every gigawatt-hour (GWh) of electricity produced.  Across the spectrum of all natural-gas power plants in the US, the average CO2 production is 519 tonnes per GWh.  That is, the geothermal power plants, which burn no fossil fuels whatsoever, produce 41% more CO2 than the run-of-the-mill natural gas power plant for the same amount of electrical energy produced.