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Wind is the flow of gases on a large scale. On Earth, wind consists of the bulk movement of air. In outer space, solar wind is the movement of gases or charged particles from the sun through space, while planetary wind is the outgassing of light chemical elements from a planet's atmosphere into space. Winds are commonly classified by their spatial scale, their speed, the types of forces that cause them, the regions in which they occur, and their effect. The strongest observed winds on a planet in our solar system occur on Neptune and Saturn.

Winds can shape landforms, via a variety of aeolian processes such as the formation of fertile soils, such as loess, and by erosion. Dust from large deserts can be moved great distances from its source region by the prevailing winds; winds that are accelerated by rough topography and associated with dust outbreaks have been assigned regional names in various parts of the world because of their significant effects on those regions. Wind affects the spread of wildfires. Winds disperse seeds from various plants, enabling the survival and dispersal of those plant species, as well as flying insect populations. When combined with cold temperatures, wind has a negative impact on livestock. Wind affects animals' food stores, as well as their hunting and defensive strategies.

Wind is caused by differences in pressure. When a difference in pressure exists, the air is accelerated from higher to lower pressure. On a rotating planet, the air will be deflected by the Coriolis effect, except exactly on the equator. Globally, the two major driving factors of large-scale winds (the atmospheric circulation) are the differential heating between the equator and the poles (difference in absorption of solar energy leading to buoyancy forces) and the rotation of the planet. Outside the tropics and aloft from frictional effects of the surface, the large-scale winds tend to approach geostrophic balance. Near the Earth's surface, friction causes the wind to be slower than it would be otherwise. Surface friction also causes winds to blow more inward into low pressure areas.

Most transportation fuels are liquids, because vehicles usually require high energy density, as occurs in liquids and solids.

First generation biofuels 'First-generation' or conventional biofuels are biofuels made from sugar, starch, and vegetable oil.

"Biofuels" are transportation fuels like ethanol and biodiesel that are made from biomass materials.

Ethanol and biodiesel are usually more expensive than the fossil fuels that they replace, but they are also cleaner-burning fuels, producing fewer air pollutants.

What Is Ethanol? Ethanol is an alcohol fuel made from the sugars found in grains, such as:

Tidal turbines look like wind turbines. They are arrayed underwater in rows, as in some wind farms. The turbines function best where coastal currents run between 3.6 and 4.9 knots (4 and 5.5 mph). In currents of that speed, a 49.2-foot (15-meter) diameter tidal turbine can generate as much energy as a 197-foot (60-meter) diameter wind turbine. Ideal locations for tidal turbine farms are close to shore in water 65.5–98.5 feet (20–30 meters) deep

just over 843,000 kilowatt-hours of electricity were provided by solar power. The vast majority of that, more than 666,500 kWh, were produced in California. Roughly 14 percent of the total renewable energy generated in the U.S. in 2008 was solar energy. And remember that these numbers continue to grow each year. The solar industry has been growing on an average of 30-40 percent each year, and as the industry grows, so will the amount of clean, renewable power it puts out. Interested in Home Solar Energy? Fill in your details below and certified solar contractors will give you FREE estimates. What type of Solar Energy services are you interested in? * Please Select Solar Electrical Solar Thermal First Name * Last Name * Zipcode *

The EIA states that just over 843,000 kilowatt-hours of electricity were provided by solar power. The vast majority of that, more than 666,500 kWh, were produced in California. Roughly 14 percent of the total renewable energy generated in the U.S. in 2008 was solar energy. And remember that these numbers continue to grow each year. The solar industry has been growing on an average of 30-40 percent each year, and as the industry grows, so will the amount of clean, renewable power it puts out.

  Fuel Cell Basics Through this website we are seeking historical materials relating to fuel cells. We have constructed the site to gather information from people already familiar with the technology–people such as inventors, researchers, manufacturers, electricians, and marketers. This Basics section presents a general overview of fuel cells for casual visitors. What is a fuel cell? How do fuel cells work? Why can’t I go out and buy a fuel cell? Different types of fuel cells.     What is a fuel cell? A fuel cell is a device that generates electricity by a chemical reaction. Every fuel cell has two electrodes, one positive and one negative, called, respectively, the anode and cathode. The reactions that produce electricity take place at the electrodes.

in general terms, hydrogen atoms enter a fuel cell at the anode where a chemical reaction strips them of their electrons. The hydrogen atoms are now “ionized,” and carry a positive electrical charge. The negatively charged electrons provide the current through wires to do work. If alternating current (AC) is needed, the DC output of the fuel cell must be routed through a conversion device called an inverter.

Oxygen enters the fuel cell at the cathode and, in some cell types (like the one illustrated above), it there combines with electrons returning from the electrical circuit and hydrogen ions that have traveled through the electrolyte from the anode. In other cell types the oxygen picks up electrons and then travels through the electrolyte to the anode, where it combines with hydrogen ions.

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.”

Hydrogen as the Main Fuel of the Future Over the last decades hydrogen, (H2) has gained more and more attention as an environmentally friendly fuel and storage medium. Combustion of pure hydrogen produces only water as exhaust. Hydrocarbon and carbon oxide emissions can only come from motor oil in the combustion chamber. Nitrous oxide emissions result from the nitrogen content in the air and increase exponentially with the combustion temperature. By using H2 in fuel cells, practically no pollution occurs. In this respect, hydrogen offers emission levels that are much lower than existing and future standards.

Hydrogen is the most common of all elements in the universe.

The desire for a long-term transition to a hydrogen society is mainly based on the need to reduce polluting and climate-affecting emissions and the concern about depletion of fossil fuel resources. Today about 90 % of the world's energy consumption is covered by fossil fuels, and most of this comes from a limited number of regions in the world. Even if hydrogen will be used on a large scale in the future, there is still a need for an energy source to produce it. Renewable energy technology such as hydro electricity, wind, wave and solar power are in principle available, but are not yet mature for mass production and/or fully developed. 

Theoretical global ocean energy resource[2] Capacity (GW) Annual gen. (TW·h) Form 5,000 50,000 Marine current power[3] 20 2,000 Osmotic power 1,000 10,000 Ocean thermal energy 90 800 Tidal energy 1,000—9,000 8,000—80,000 Wave energy

In 2006, wind power supplied 0.6% of US electricity but reduced CO2 emission from electricity production by a full 1%.

What really matters is the cost to society. With current subsidy methods, it costs around 3¢/kWh

  One-Time Cost per kW Capacity (usage) Factor Fixed Cost per kWh Variable Cost per kWh Total Cost per kWh Gas Turbine $439 15% 5.2¢ 8.7¢ 13.9¢ Coal $1,338 90% 2.7¢ 1.9¢ 4.5¢ Nuclear $2,180 90% 4.3¢ 0.3¢ 4.6¢ Wind $1,254* 30% 7.5¢ 0.0¢ 7.5¢

With a key federal tax incentive about to expire, the U.S. installed a 5.5 gigawatts of wind power in December to cap off a year that saw a record 13.2 gigawatts of wind energy come online, according to a report released Friday by research firm Bloomberg New Energy Finance. The U.S. now boasts a total of 60 gigawatts of wind energy, accounting for 6% of the nation’s total generating capacity. According to Bloomberg New Energy Finance, wind power prices have dropped more than 21% since 2010. Falling prices and the looming expiration of the production tax credit, which pays a premium for wind energy, unleashed a wind farm building boom last year. “It’s clear that the economics, aided by the PTC, drove wind growth in 2012,” Amy Grace, a wind analyst with Bloomberg New Energy Finance, said in a statement. “Eleven gigawatts of capacity was built in states without any near-term state mandated demand.

Wind power in the United States is a branch of the energy industry, expanding quickly over the last several years. Construction of new wind power generation capacity in the fourth quarter of 2012 totaled 8,380 megawatts (MW) bringing the cumulative installed capacity to 60,007 MW.[1] This capacity is exceeded only by China.[2] For the 12 months until July 2013, the electricity produced from wind power in the United States amounted to 157.8 terawatt-hours, or 3.91% of all generated electrical energy.[3]

The first tidal power station was the Rance tidal power plant built over a period of 6 years from 1960 to 1966 at La Rance, France.[8] It has 240 MW installed capacity.

Historically, tide mills have been used, both in Europe and on the Atlantic coast of North America. The incoming water was contained in large storage ponds, and as the tide went out, it turned waterwheels that used the mechanical power it produced to mill grain. [1] The earliest occurrences date from the Middle Ages, or even from Roman times.[2][3] It was only in the 19th century that the process of using falling water and spinning turbines to create electricity was introduced in the U.S. and Europe.[

Solar energy, radiant light and heat from the sun

radiant light and heat from the sun,

kilowatt system will replace around 2.5 tonnes of greenhouse gases, possibly more. It depends on what your annual output is, and what the local mix of power sources is in your province/state/country.