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Wave energy technologies extract energy directly from surface waves or from pressure fluctuations below the surface. Renewable energy analysts believe there is enough energy in ocean waves to provide up to 2 terawatts of electricity. (A terawatt is equal to a trillion watts.)

One of the most important is that wind power is the least expensive of all other forms of alternative energy.

Another tremendous benefit of wind power is that it is a sustainable source of energy and a clean source of energy

The U.S. consumes a little more than 20 million barrels of oil a day. The largest end uses are motor gasoline (9 million barrels) and diesel (4 million barrels). That works out to about 140 billion gallons of gasoline and 60 billion gallons of diesel a year. In 2006, the U.S. consumed nearly 5.4 billion gallons of ethanol, 12 percent of which was imported. Adjusting for its lower energy content, that amounted to about 2.5% of the total U.S. demand for gasoline. Biodiesel consumption was much lower, about 250 million gallons in 2006.

The U.S. consumes a little more than 20 million barrels of oil a day. The largest end uses are motor gasoline (9 million barrels) and diesel (4 million barrels). That works out to about 140 billion gallons of gasoline and 60 billion gallons of diesel a year. In 2006, the U.S. consumed nearly 5.4 billion gallons of ethanol, 12 percent of which was imported. Adjusting for its lower energy content, that amounted to about 2.5% of the total U.S. demand for gasoline. Biodiesel consumption was much lower, about 250 million gallons in 2006. In the Energy

The U.S. consumes a little more than 20 million barrels of oil a day. The largest end uses are motor gasoline (9 million barrels) and diesel (4 million barrels). That works out to about 140 billion gallons of gasoline and 60 billion gallons of diesel a year. In 2006, the U.S. consumed nearly 5.4 billion gallons of ethanol, 12 percent of which was imported. Adjusting for its lower energy content, that amounted to about 2.5% of the total U.S. demand for gasoline. Biodiesel consumption was much lower, about 250 million gallons in 2006. In the Energy Policy Act of 2005, Congress enacted the Renewable Fuels Standard, which requires an annual increase in biofuels use to 7.5 billion gallons by 2012. The chart above details past levels of U.S. ethanol production and the minimum levels set by the Renewable Fuels Standard. In the 2006 State of the Union address, President Bush announced a goal of replacing “more than 75% of our oil imports from the Middle East by 2025.” According to the Department of Energy, meeting that goal will require 60 billion gallons of biofuels a year. A year later, the President accelerated the timetable and called for “20 in 10.”

Advantages

Solar energy is free - it needs no fuel and produces no waste or pollution.

Handy for low-power uses such as solar powered garden lights and battery chargers, or for helping your home energy bills.

Solar energy is energy from the sun, it is a renewable source of energy and does not cause pollution.

Solar energy is the radiant energy produced by the Sun. It is both light and heat

What is solar energy? Solar energy is the radiant energy produced by the Sun. It is both light and heat. It, along with secondary solar-powered resources such as wind and wave power, account for the majority of the renewable energy on Earth.

The United States uses about 4,000 terawatt hours (TWh) of electricity per year. DOE estimates that the maximum theoretical electric generation that could be produced from waves and tidal currents is approximately 1,420 TWh per year, approximately one-third of the nation's total annual electricity usage.

calculate the maximum kinetic energy available from waves and tides off U.S. coasts that could be used for future energy production, and which represent largely untapped opportunities for renewable energy development in the United States.

The West Coast, including Alaska and Hawaii, has especially high potential for wave energy development, while significant opportunities for wave energy also exist along the East Coast. Additionally, parts of both the West and East Coasts have strong tides that could be tapped to produce energy.

As a renewable energy, offshore wind and wave energy can provide a constant energy supply that solar and onshore wind lack, he said.

Future Of Geothermal Energy The future of geothermal energy depends on three factors: it's demand, supply and it's competitiveness among other renewable resources in terms of cost, availability, reliability etc.. Demand for geothermal energy is going to increase and increase with the increase in the population and extinction of other non-renewable sources. Moreover, today government also support the resources which are cleaner and do not spoil the environment. Supply of geothermal energy is limited and confined to certain areas only.

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.  

"Worldwide, approximately 3000 gigawatts (1 gigawatt = 1 GW = 1 billion watts) of energy is continuously available from the action of tides.

The best areas are on the eastern sides of the oceans (western side of the continents) between the 40 and 60 latitudes in both the northern and southern hemispheres.

While the "wave power at deep ocean sites is three to eight times the wave power at adjacent coastal sites," constructing and mooring the site and transmitting the electricity to shore would be prohibitively costly.

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

The argument for tidal power is overwhelming: it’s a practically infinite supply of clean energy and has one of the smallest carbon footprints of any power source; it’s reliable, cost-efficient, has minimal effect on the marine environment and virtually zero effect on sea-gazing aesthetics. Most importantly, The World Energy Council estimates that the energy that can be harvested from world’s oceans is equal to twice the electricity that the world produces now

1 MW of wind energy can offset approximately 2,600 tons Waste heat recovery  file size 4MB of carbon dioxide annually.

29,440 Megawatts (MW) of wind energy are currently installed in the United States, and an additional 5,866 MW are under construction.Over 8,500 MW were installed in the US in 2008 (just beating out China with 6,300 MW). This represents: 50 percent increase from 200742 percent of all new generating capacity installed in 2008$17 billion investment44 million tons of carbon emissions avoided (equivalent of 7 million cars)35,000 new jobs

The constant temperature of the Earth creates underground sources of heat, hot water and steam which become fuel to produce geothermal energy. People have used various forms of geothermal energy for hundreds of years; modern technology accesses these underground reservoirs, steam deposits and hot air by drilling, and then using the heat or hot water directly or using it to create power. Geothermal energy represents an enormous, underused power source that provides clean, renewable energy in virtually unlimited supply.

Hydrogen is colorless, odorless, tasteless and non-toxic. It is a gas at temperatures above -423° F and is highly diffuse, having a density approximately 14 times less than that of air. Because it is buoyant and diffusive, hydrogen dissipates quickly in open areas and can move through small spaces, which makes it difficult to store. Hydrogen is flammable over a broad range of gas concentration (from 4 to 74 percent), although its lower flammability limit – that is, the lowest temperature and pressure at which it will combust – is higher than those for some common fuels such as gasoline, propane or diesel.1 Hydrogen has been described as “the fuel of the future.” On Earth, hydrogen is found in combination with other elements such as carbon (hydrocarbons), oxygen (water) and nitrogen (ammonia). Although hydrogen may sometimes be used as a fuel, it is most often used as an energy carrier, such as electricity, and not an energy source. To make hydrogen a usable, stand-alone fuel, it must be separated from these other elements by chemical, thermal or electrochemical processes.

History British scientist Henry Cavendish identified hydrogen as a distinct element in 1766. Subsequent experiments by British and French scientists resulted in the first flight of a hydrogen balloon and the discovery that applying electricity to water can produce hydrogen and oxygen.

In the 1960s, NASA space capsules used hydrogen fuel cells for onboard electric power, heat and water.

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.