Wind Energy

Wind energy • Energy from wind power is becoming an increasingly significant source of energy • (considering that the price of oil is getting dearer) 1. this specially so for oil deficient developing nations like India which meet their energy needs by importing oil. 2. providing fact and figures analyze the opportunities and challenges that wind energy companies face in setting up wind farms in India. ▪ Also do u think wind energy is viable if the government decide to stop extending subsidies? interoduction The inevitable consequence of fossil fuels is that they are finite and will run out eventually. At the moment resources like oil and gas are at premium rates. Whether this is being driven by market forces or these resources are genuinely becoming scarce is debatable. What isn't debatable is that governments and the general population are beginning to feel the pinch of these prices and are looking for alternatives. Solar power and wind energy have been popular ways to create energy for many centuries but have been largely ignored by governments and utilities companies because they were reliant on the elements which, in a word, were unreliable. However for individual properties in the right environments they are useful. They have the added advantage that they are renewable and do not give off greenhouse gases that harm the environment. This article will look at some of the issues around solar power and wind energy.
Solar and wind power are quite straightforward in how they work. Solar power derives its energy from the sun, either passively through direct heating or actively through photovoltaic cells that convert photons to electricity.
Wind energy is derived from the air that is converted to mechanical energy, in the shape of a turbine, that can then be used directly or to create electricity.
Advantages of Solar and Wind Power
There are quite a few advantages to solar and wind power. The energy is free after installation and the equipment requires minimal maintenance. Both methods are pollution-free with no greenhouse gases emitted.
In terms of solar power, little maintenance is needed for the solar panels. A wind turbine does not interfere with the land around it so this can be used for animals to graze or planting of crops. In other words, the land is not totally wasted with the wind power turbines.
Disadvantages of Solar Power and Wind Energy
Both of these forms of energy creation are reliant on the elements, however further research, especially in solar technology, is making these systems more efficient. Japan and Germany lead the way in solar research and these countries are not noted for long periods of sunshine throughout the year.
Wind power can be quite noisy because of the spinning of the turbine blades. Depending on how big the turbine is, some people may think that the structure is unsightly and ruins the landscape.
With both solar and wind power, a lot of turbines and reflectors are needed to make a significant energy impact for an area. And with solar power, the cells that capture the energy produce DC power which must then be converted to AC power.
With solar power, solar heat and electricity cannot be produced at night or when there is no direct sunlight, so complementary power sources must be used as a contingency. Many people that live off the grid utilize solar power, wind energy and a generator as their energy sources. The generator is the ultimate back up but the solar and wind power can be combined to produce all the households needs provided the house is insulated adequately.
Solar power and wind energy are the way to go in remote areas like farms or countries with under developed utility infrastructures. However it may not be too far away in the towns and cities. This is especially the case of solar panels, that are fairly unobtrusive and have many incentives and rebates to use them
Wind energy certainly is viable in many parts of the world without subsidy. We came dangerously close to finding out exactly how viable it would be this year in the U.S., when an extension of the Production Tax Credit (PTC) was extended into 2009 at the last minute as one of the "sweeteners" that got the $700 billion Wall St bailout passed. http://www.nicholas.duke.edu/nicholas/in... The current subsidy for wind energy in the U.S. is PTC, which is a tax credit currently equal to 2 cents per kWh. The price for electricity varies significantly by region, so some regions are more closely tied to the PTC than others to make the economics of a wind project work out. For example, the price for electricity is only about 4.5 cents per kWh in the Midwest (e.g. Oklahoma, Kansas, North Dakota), so that extra 2 cent per kWh makes a huge difference. In other parts of the country (California, Hawaii, New England), the price of electricity is over 10 cents per kWh, so the 2 cent tax credit is relatively less valuable there.

The bottom line is that there are several places under development now in the U.S. that are good enough to justify being built without the 2 cents per kWh tax credit - these select locations are very windy, close to a transmission line, and/or in areas with high electricity prices. Without the subsidy, the growth of wind energy in the United States (same goes for the rest of the world, to my knowledge) would be severely affected. Thousands of people would be laid off, a significant portion of projects would be canceled, and we'd all go back to burning lots of cheap and dirty coal, nuclear, hydro, and finally natural gas to fill off the balance of our energy needs.

Regarding your question about oil imports in countries like India, I think you might be slightly misguided. Wind energy does not provide fuel for transportation, just electricity. Until we have a way to develop the hydrogen economy (http://auto.howstuffworks.com/hydrogen-e... convert electricity to hydrogen fuel, distribute it through a nationwide infrastructure we don't have, and put it in cars that are currently cost-prohibitive), we will remain addicted to oil. The alternative to oil (for now) is ethanol. Especially in places like Brazil, which have plenty of land and a great climate for growing sugar cane ethanol rather than the subsidized corn ethanol we produce here in the U.S.

Wind energy is the cheapest form of renewable energy currently available, and it will get cheaper in the coming years as the credit crisis corrects what has been a massive seller's market for wind turbines in the last few years. Competition in wind turbine manufacturing is up, and the cost of steel (the 80 m towers) and cement (the massive foundations) is down. These factors will lead to wind energy becoming cheaper in the next few years. Wind energy can be cost-competitive with natural gas, offsetting our need for this finite resource and (hopefully) lowering prices for consumers. That's the long-term benefit of the subsidy - get the industry built up now so we will be well set for a future of increasingly scarce oil and natural gas, which will be imported from unstable regions of the world.
'Wind energy is the fastest growing energy source'

Shakti S. Singh

—Dr. Sunil Motiwal, Former Director General, Indian Wind Turbine Manufacturers' Association and President, Matrix Consulting Group

What are the prospects for non-conventional energy source?
Renewable energy sources offer viable options to address energy security concerns in a country. Today, India has one of the highest potentials for the effective use of renewable. There is significant potential for generation of power from renewable energy sources, such as wind, small hydro, biomass and solar energy. Therefore a special emphasis has been laid on the generation of grid quality power from renewable sources of energy. Currently, we see the focus on non-conventional energy missing in India. We are exporting solar and wind power equipment worth Rs 1,200 crore.
Why haven't alternative sources of energy taken off in a big way?
The general public has to proactively adopted products and services based on non-conventional energy sources. This has not yet happened in India. The ministry of new and renewable energy has taken efforts to popularise these sources of energy and will do more through audiovisual, print and other mediums. In addition, there is need to educate schools and colleges about the use of alternative energy.
What is the scenario in wind power generation in India and abroad?
Worldwide five nations, Germany, USA, Denmark, Spain and India, account for 80 per cent of the world's installed wind energy capacity. Wind energy continues to be the fastest growing renewable energy source with worldwide wind power installed capacity reaching 14,000 mw.
With a number of international players having set up manufacturing facilities here, the country is rapidly emerging as a manufacturing and knowledge hub for wind power development.
Explain the potential of wind energy in India.
India has the potential to produce as much as 45,000 mw. The whole world is focusing on non-conventional energy but we see this is missing in India. It is the only source where the power cost freezes in the beginning and does not increase. The government will have to give top priority to this sector.
Growth in conventional power generation has been limited due to fuel transportation problems, new environmental regulations and long gestation period. As against this, wind electric power generation can be put on line in as low as six months. Also, wind power is green energy with free fuel and it comes with a lot of financial incentives. Wind power generation is emerging as an attractive business activity in the country.
What are the focus issues and non-issues for wind power generation?
There are many issues that directly affect the progress on planning wind farms in India. One of them is availability of land. India being an agricultural oriented country, most of the land is in private hands which is not freely available. On the other hand, the government land is mostly in the form of reserve forests and is again unavailable.
Whatever small quantity of land was available, has been booked by big WEG manufacturers and is available on premium along with their machines.
Other major issues are size of WEG, plant load factor, generation guarantee, O&M cost over the lifecycle of machines, grid availability, financial incentives, disposal of wind farm, etc.
The factors that are non-issue in today's scenario of wind power generation in India, surprisingly are: individual machine capacity, equipment specification and technology: tower type, its height or its foundation, availability, efficiency or loading of wind generators, location/distance from utility centre; micro-sitting or wind farm design.

Wind is simple air in motion. It is caused by the uneven heating of the earth’s surface by the sun. Since the earth’s surface is made of very different types of land and water, it absorbs the sun’s heat at different rates.
During the day, the air above the land heats up more quickly than the air over water. The warm air over the land expands and rises, and the heavier, cooler air rushes in to take its place, creating winds. At night, the winds are reversed because the air cools more rapidly over land than over water.
In the same way, the large atmospheric winds that circle the earth are created because the land near the earth's equator is heated more by the sun than the land near the North and South Poles.
Today, wind energy is mainly used to generate electricity. Wind is called a renewable energy source because the wind will blow as long as the sun shines.

The History of Wind

Since ancient times, people have harnessed the winds energy. Over 5,000 years ago, the ancient Egyptians used wind to sail ships on the Nile River. Later, people built windmills to grind wheat and other grains. The earliest known windmills were in Persia (Iran). These early windmills looked like large paddle wheels. Centuries later, the people of Holland improved the basic design of the windmill. They gave it propeller-type blades, still made with sails. Holland is famous for its windmills.
American colonists used windmills to grind wheat and corn, to pump water, and to cut wood at sawmills. As late as the 1920s, Americans used small windmills to generate electricity in rural areas without electric service. When power lines began to transport electricity to rural areas in the 1930s, local windmills were used less and less, though they can still be seen on some Western ranches.
The oil shortages of the 1970s changed the energy picture for the country and the world. It created an interest in alternative energy sources, paving the way for the re-entry of the windmill to generate electricity. In the early 1980s wind energy really took off in California, partly because of state policies that encouraged renewable energy sources. Support for wind development has since spread to other states, but California still produces more than twice as much wind energy as any other state.
The first offshore wind park in the United States is planned for an area off the coast of Cape Cod, Massachusetts (read an article about the Cape Cod Wind Project).

HOW WIND MACHINES WORK

Like old fashioned windmills, today’s wind machines use blades to collect the wind’s kinetic energy. Windmills work because they slow down the speed of the wind. The wind flows over the airfoil shaped blades causing lift, like the effect on airplane wings, causing them to turn. The blades are connected to a drive shaft that turns an electric generator to produce electricity.
With the new wind machines, there is still the problem of what to do when the wind isn’t blowing. At those times, other types of power plants must be used to make electricity.

TYPES OF WIND MACHINES

There are two types of wind machines (turbines) used today based on the direction of the rotating shaft (axis): horizontal–axis wind machines and vertical-axis wind machines. The size of wind machines varies widely. Small turbines used to power a single home or business may have a capacity of less than 100 kilowatts. Some large commercial sized turbines may have a capacity of 5 million watts, or 5 megawatts. Larger turbines are often grouped together into wind farms that provide power to the electrical grid.
Horizontal-axis
Most wind machines being used today are the horizontal-axis type. Horizontal-axis wind machines have blades like airplane propellers. A typical horizontal wind machine stands as tall as a 20-story building and has three blades that span 200 feet across. The largest wind machines in the world have blades longer than a football field! Wind machines stand tall and wide to capture more wind.
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Vertical-axis
Vertical–axis wind machines have blades that go from top to bottom and the most common type (Darrieus wind turbine) looks like a giant two-bladed egg beaters. The type of vertical wind machine typically stands 100 feet tall and 50 feet wide. Vertical-axis wind machines make up only a very small percent of the wind machines used today.
The Wind Amplified Rotor Platform (WARP) is a different kind of wind system that is designed to be more efficient and use less land than wind machines in use today. The WARP does not use large blades; instead, it looks like a stack of wheel rims. Each module has a pair of small, high capacity turbines mounted to both of its concave wind amplifier module channel surfaces. The concave surfaces channel wind toward the turbines, amplifying wind speeds by 50 percent or more. Eneco, the company that designed WARP, plans to market the technology to power offshore oil platforms and wireless telecommunications systems.

WIND POWER PLANTS

Wind power plants, or wind farms as they are sometimes called, are clusters of wind machines used to produce electricity. A wind farm usually has dozens of wind machines scattered over a large area. The world's largest wind farm, the Horse Hollow Wind Energy Center in Texas, has 421 wind turbines that generate enough electricity to power 220,000 homes per year.
Unlike power plants, many wind plants are not owned by public utility companies. Instead they are owned and operated by business people who sell the electricity produced on the wind farm to electric utilities. These private companies are known as Independent Power Producers.
Operating a wind power plant is not as simple as just building a windmill in a windy place. Wind plant owners must carefully plan where to locate their machines. One important thing to consider is how fast and how much the wind blows.
As a rule, wind speed increases with altitude and over open areas with no windbreaks. Good sites for wind plants are the tops of smooth, rounded hills, open plains or shorelines, and mountain gaps that produce wind funneling.
Wind speed varies throughout the country. It also varies from season to season. In Tehachapi, California, the wind blows more from April through October than it does in the winter. This is because of the extreme heating of the Mojave Desert during the summer months. The hot air over the desert rises, and the cooler, denser air above the Pacific Ocean rushes through the Tehachapi mountain pass to take its place. In a state like Montana, on the other hand, the wind blows more during the winter. Fortunately, these seasonal variations are a good match for the electricity demands of the regions. In California, people use more electricity during the summer for air conditioners. In Montana, people use more electricity during the winter months for heating.

WIND PRODUCTION

In 2006, wind machines in the United States generated a total of 26.6 billion kWh per year of electricity, enough to serve more than 2.4 million households. This is enough electricity to power a city larger than Los Angeles, but it is only a small fraction of the nation's total electricity production, about 0.4 percent. The amount of electricity generated from wind has been growing fast in recent years. In 2006, electricity generated from wind was 2 1/2 times more than wind generation in 2002.
New technologies have decreased the cost of producing electricity from wind, and growth in wind power has been encouraged by tax breaks for renewable energy and green pricing programs. Many utilities around the country offer green pricing options that allow customers the choice to pay more for electricity that comes from renewable sources.
Wind machines generate electricity in 28 different states in 2006. The states with the most wind production are Texas, California, Iowa, Minnesota, and Oklahoma.
Most of the wind power plants in the world are located in Europe and in the United States where government programs have helped support wind power development. The United States ranks second in the world in wind power capacity, behind Germany and ahead of Spain and India. Denmark ranks number six in the world in wind power capacity but generates 20 percent of its electricity from wind.

WIND AND THE ENVIRONMENT

In the 1970s, oil shortages pushed the development of alternative energy sources. In the 1990s, the push came from a renewed concern for the environment in response to scientific studies indicating potential changes to the global climate if the use of fossil fuels continues to increase. Wind energy is an economical power resource in many areas of the country. Wind is a clean fuel; wind farms produce no air or water pollution because no fuel is burned. Growing concern about emissions from fossil fuel generation, increased government support, and higher costs for fossil fuels (especially natural gas and coal) have helped wind power capacity in the United States grow substantially over the last 10 years.
The most serious environmental drawbacks to wind machines may be their negative effect on wild bird populations and the visual impact on the landscape. To some, the glistening blades of windmills on the horizon are an eyesore; to others, they’re a beautiful alternative to conventional power plants.