A Small Summary

The following are some of the questions that I am studying on and the answers I have found. I have generally summarized it and thus to post them out.

-The physics principle behind wind energy?

Basically, the physics principle is called The Law of Conversion of Energy. The principle states that energy cannot be created or destroyed, it can only be changed from one form to another. The total quantity of matter and energy available in the universe is a fixed amount and never any more or less.

In our case, the Law of Conversion of Energy is applied on the wind energy. The wind energy is converted into other forms of energy that can be used by human directly.

-How the method actually work?

An exemplary embodiment includes a wind turbine system. The wind turbine system includes a wind turbine generator operable to supply wind turbine power to a utility system. A converter is coupled to the wind turbine generator and the utility system. The wind turbine system also includes a controller comprising an internal reference frame of the wind turbine generator, coupled to the converter, and configured for modulating flow of power through the converter in response to frequency disturbances or power swings of the utility system relative to the internal reference frame.

Wind turbine generators are regarded as environmentally friendly and relatively inexpensive alternative sources of energy that utilize wind energy to produce electrical power. A wind turbine generator generally includes a wind rotor having turbine blades that transform wind energy into rotational motion of a drive shaft, which in turn is utilized to drive a rotor of an electrical generator to produce electrical power. Modern wind power generation systems typically take the form of a wind-farm having multiple such wind turbine generators that are operable to supply power to a transmission system providing power to a utility system.


In traditional power systems, the frequencies of the synchronous generators of the power system match the utility system and the dynamic response of the frequency of the utility system is dependent upon the inertia of the synchronous generators and loads. Synchronous generators used in a traditional power system are able to contribute in frequency and voltage control of the power system during transient conditions, that is, sudden failure of generation, line fault or connection of a large load. During of transient conditions, the system frequency starts to change at a rate mainly determined by the total angular momentum of the system. The total angular momentum is a sum of the angular moment of all the generators and rotating loads connected to the power system. In such transient conditions, the synchronous generators may also provide additional control services that modulate active power to stabilize the power system and restore frequency to its nominal value.

Reference:
http://www.freshpatents.com/System-and-method-for-utility-and-wind-turbine-control-dt20070531ptan20070120369.php

-The importance of producing wind energy?

Why do we have to develop wind energy so urgently. There are two main reasons.

1)Environment protection.

Reducing global warming.
The build-up of global warming pollution is not only causing a gradual rise in average temperatures, but also increasing fluctuations in weather patterns and causing more frequent and severe droughts and floods.
As everyone knows, the burning of fossil fuel will produce a large amount of carbon dioxide, and the use of wind energy will greatly reduce the situation. From specific research, US scientists find that using wind energy can help reduce total U.S. emissions of carbon dioxide by almost a third. Since carbon dioxide is the major pollutant which contributes to global warming by trapping the sun's rays on the earth as in a greenhouse, the decrease of carbon dioxide in the atmosphere means a new hope for us.

Preventing acid rain.
Sulfur dioxide and nitrogen oxide are two most important sources of acid rain while the burning of fossile fuel will greatly produce sulfur dioxide and nitrogen oxide.The use of wind energy will largely prevent the acid rain. For example,in the United States, development of just 10% of the wind potential in the 10 windiest U.S. states would not only provide more than enough energy to displace emissions from the nation's coal-fired power plants but also eliminate the nation's major source of acid rain.

2) The urgency of fossil fuel.

Traditionally, people get the energy that can be directly used by burning fossil fuel and converting it. However, as the larger and larger amount of usage of fossil fuel, the resource of fossil fuel becomes very urgent now and it takes millions of years to form fossil fuel. As a result, it is very important to find a new resource of energy to replace it and wind energy is a quite ideal energy to be used now.(The reason can be seen in Yeiqi's post).

By Xiaolu

If is suitable to use wind energy in Singapore

As everyone knows, Singapore is a small island country with limited land resources, so currently, it would be impractical to use wind energy in Singapore. However, if technology progresses and wind turbines can be installed on rooftops just like solar panels, than Singapore would be able to enjoy the wind energy and this would improve Singapore's self-sustainability of energy.

By Peiqi

The Present State of Energy Resource in Singaproe

Singapore is a small island country with little natural resources. As Singapore's economy grows rapidly since the last few decades, the country's energy comsumption have also risen steadily. Today, about 80% of Singapore's electricity is generated by importing gas from Indonesia and Malaysia.

Many renewable energy sources such as geothermal, hydro, wind and tidal sources are not viable at present. Solar energy is feasible but expensive compared to conventional fuel even at today's high oil price.

Singapore is looking for ways to harness solar, wind and other renewable sources in a cheaper and more efficient way.

Reference: http://app.mti.gov.sg/default.asp?id=148&articleID=5621

By Peiqi

Wind Energy in China

China has abundant wind energy resources that provide potential for large-capacity wind farms. China built its first wind farm in Rongcheng, Shandong in 1986. By the end of 2005, China had built 59 wind farms with 1,854 wind turbine generators, ranking it number ten globally.

Today, wind power in China is developing rapidly and is supported by the government. By 2020, China plans to have 30 gigawatts of wind power.

Liaoning, Xinjiang, Inner Mongolia, and Guangdong are the main areas in China that wind energy development took place. Currently, Xinjiang's Dabancheng is the largest wind farm in China, with 100 megawatts of power generating capacity.

To support wind power technology development in China, the Chinese government has implemented a number of projects and stipulated a serious of economic incentive policies such as the Ride the Wind Program, the National Debt Wind Power Program and the Wind Power Concession Project.

For more information, please visit http://www.ecoworld.com/home/articles2.cfm?tid=390

Reference: http://www.ecoworld.com/home/articles2.cfm?tid=390

By Peiqi

Negative impacts of wind energy

Erosions
Erosion can be a concern in certain habitats such as the desert, where a hard-packed soil surface must be disturbed to install wind turbines. Erosion has also been raised as a concern in the eastern U.S., where wind farms typically must be installed on mountain ridgelines.
Solution: Standard engineering practices used by ski areas on the same kind of terrain are adequate to deal with any erosion issues that might be raised by construction of a wind farm and its service road.
Birds and bats kills
Birds occasionally collide with wind turbines, as they do with other tall structures such as buildings. Avian deaths have become a concern at Altamont Pass in California, which is an area of extensive wind development and also high year-round raptor use.
Solution: Wind’s overall impacts on birds are low compared with other human-related sources of avian mortality—see "Avian Collisions With Wind Turbines," for more information.
Affect lives of wild animals
Wind energy can also have negative impact on other wildlife by fragmenting habitat, both through installation and operation of wind turbines themselves. Also, the roads and power lines that are built will do harm to those wild animals.
Solution: This has been raised as an issue in areas with unbroken stretches of forests. More research is needed to better understand these impacts.
Noise
During early times, noise was a serious problem with wind turbine designs as it disturbed people who lived nearby a lot, but it has been largely eliminated as a problem through improved engineering and through appropriate use of setbacks from nearby residences.
Solution: Aerodynamic noise has been reduced by changing the thickness of the blades' trailing edges and by making machines "upwind" rather than "downwind" so that the wind hits the rotor blades first, then the tower
Shadow flicker
Shadow Flicker is often raised as an issue by close neighbors of wind farm projects. A wind turbine's moving blades can cast a moving shadow on a nearby residence, depending on the time of the year (which determines how low the sun is in the sky) and time of day.
Solution: A bit of careful planning, and the use of good software to plan your wind turbine site can help you resolve this problem, however. If you know where the potential flicker effect is of a certain size, you may be able to place the turbines to avoid any major inconvenience for the neighbors.

http://www.awea.org
American wind energy association

(Yeqi)

Positive impacts of wind energy

Environmental
Reducing global warming
The build-up of global warming pollution is not only causing a gradual rise in average temperatures, but also increasing fluctuations in weather patterns and causing more frequent and severe droughts and floods. From specific research, US scientists find that using wind energy can help reduce total U.S. emissions of carbon dioxide by almost a third. Since carbon dioxide is the major pollutant which contributes to global warming by trapping the sun's rays on the earth as in a greenhouse, the decrease of carbon dioxide in the atmosphere means a new hope for us.
Help to prevent acid rain
Acid rain harms forests and the wildlife they support. Many lakes in the U.S. Northeast have become biologically dead because of this form of pollution. Acid rain also corrodes buildings and economic infrastructure such as bridges. Sulfur dioxide and nitrogen oxides are two most important sources of acid rain. However, development of just 10% of the wind potential in the 10 windiest U.S. states would not only provide more than enough energy to displace emissions from the nation's coal-fired power plants but also eliminate the nation's major source of acid rain.
Ensure people’s health
Particulate matter is of growing concern because of its impacts on health. Its presence in the air along with other pollutants has contributed to make asthma one of the fastest growing childhood ailments in industrial and developing countries alike, and it has also recently been linked to lung cancer. Since wind energy is a kind of clean energy, it will help contain the spread of asthma and other respiratory diseases aggravated or caused by air pollution in the country.
Protect biological food chain
Toxic heavy metals accumulate in the environment and up the biological food chain. A number of states have banned or limited the eating of fish from fresh-water lakes because of concerns about mercury, a toxic heavy metal, accumulating in their tissue. By using wind energy, it is estimated that such conditions will reduce and the negative impacts of heavy metals will be controlled.

Economical
Saving money
As with every other study of non-economic costs that has been conducted, the Externe study found wind energy's costs to be among the lowest, far below those of fossil fuels. The highest non-economic cost for wind in any European country, for example, was 0.25 Euro cents per kilowatt-hour, while the lowest cost for coal was 2-4 Euro cents/kWh (eight to 16 times as much).
Saving living area
In open, flat terrain, a utility-scale wind plant will require about 60 acres per megawatt of installed capacity. However, only 5% (3 acres) or less of this area is actually occupied by turbines, access roads, and other equipment--95% remains free for other compatible uses such as farming or ranching.
Saving water
Water is very important in energy production, particularly in areas where water is scarce. This is because conventional power plants need large amounts of water for the condensing portion of the thermodynamic cycle. Different kinds of conventional power plants consume different amounts of water. Here is a diagram which shows the water consumption of some kinds of conventional power plants (through evaporative loss, not including water that is recaptured and treated for further use):
WATER CONSUMPTION--CONVENTIONAL POWER PLANTS

Technology ________gallons/kWh ___________liters/kWh

Nuclear___________0.62 _________________ 2.30

Coal_____________0.49 __________________1.90

Oil______________0.43__________________1.60

Combined Cycle Gas__0.25 __________________0.95

related wbsites:
http://www.repp.org/repp_pubs/repp_publications.html
http://www.externe.info/externpr.pdf
(He Yeqi)

Public attitudes to wind energy

It's more popular than you
might have been told!
Many people believe
that wind farms are noisy and can disturb the lives of locals. On the
contrary,
people who live near a wind farm and have direct experience of it
generating
electricity tend to be more positive than those who do not.
Indeed, recent
studies has shown that the closer people live to a wind farm
the more supportive
they are of both the project and wind power as an energy
source.
In fact,
wind energy is one of the most popular of the energy
technologies. Certainly if
you were to ask people which form of power
generation they would like to see
more of, the answer is least likely to be
nuclear, oil, coal or gas. More than
eight out of ten people are in favor of
wind energy and less than one in ten
against it. However, this 5% often have
the most to say and certainly say it the
loudest, which often creates the
impression that wind farms are very unpopular.

provided by: Yeqi :)

Minutes for discussion 1

23rd,April,2008
Discussion on our poster

In our SIA procedure, we are supposed to design our own poster which is able to reveal our main ideas about the topic(wind energy).
On 23rd,April,2008,we discussed on the contents of our poster. In the end, we decided our main points and theme of our slogan.
The main points of the poster should include physics principle of wind energy, energy conversion,the advantages of using wind energy(It is renewable, good for saving fossil fuel and doing no harm to our environment) as well as the lack of fossil fuel nowadays.
Also, the theme of our slogan is to arouse public awareness of protecting environment by using clean energy especially wind energy.
Finally, we arranged the time and venue to do our first draft. We decided to do it on Monday afternoon, Term 2,Week 10 outside Nanyang Girls' Boarding School. Meanwhile, we may consider how to bring out ideas in details.

The definition and introduction of wind energy

"Wind Energy"

Energy received from the movement of the wind across the earth. This energy is a result of the heating of our oceans, earth, and atmosphere by the sun.

The wind is caused by the uneven heating of the surface of our earth by the sun. The reason for the uneven heating is due to the different surfaces of our earth (land and water).

Air above land mass heats up more rapidly during the day time, while the air above water will heat up at a slower rate. As the air above the land rises and expands (due to heating), the cooler air above the water will rush in to fill its place. It is this process which causes the wind the blow, as the wind is the force of air rushing to fill a gap.

During the night, the process is slightly different, and instead of the air heating, the air cools. The air above land mass will loose heat more rapidly than the air above the water, resulting in air from the land rushing to fill air over the water.
Larger winds are generally found closer to the equator, as the air will generally heat and cool more rapidly, reducing in a greater wind force.

We are able to harness energy from the wind, and turn this into renewable electricity. Wind energy is reliable providing the correct location and most appropriate wind turbine design is researched.

There are numerous wind energy facts available as Yeqi said, which will provide additional information on wind energy, and help to provide a more detailed definition of this form of energy.

The wind will blow as long as the sun shines down on earth. As more efficient wind harnessing technologies become available, we will be able to take advantage of this clean, renewable energy source.


The website referred:www.clean-energy-ideas.com

p.s sorry for pasting too late
Xiaolu:)

Wind Energy Case Study: China

This is the link to a case study of the use of wind energy in China, pls go in and take a look http://www.ecoworld.com/home/articles2.cfm?tid=390

Peiqi

How the United States use wind energy?

Windmills are sprouting across the United States, as Americans search for non-polluting alternative energy sources. The West Coast state of California is the U.S. leader in wind power.
Wind turbines dot hillsides in several parts of the state, including Tehachapi, in the desert northeast of Los Angeles.

Lee Brace of G.E. Energy stands beneath a slow-spinning propeller, attached to a wind turbine that his company is testing. "The larger the blade, it seems the slower they move. You're looking at 58 meters blades, and three of them on top of the tower there, about 240 feet up in the air."
The tower is 75 meters tall, and atop it is a one-point-five megawatt turbine, which provides enough power for 500 houses.

More than 4,000 wind turbines dot these desert hillsides. Some date from the 1980s and are just a fraction of the size and output of this model.

Down the road, Oak Creek Energy Systems operates 200 turbines, including another massive one-point-five megawatt test model. Michael Burns sits in front of a bank of computer monitors, which use color codes to track the temperature and status of the windmills. "The green ones are on line. If it's white, it means the turbine is off. Everything is all right on it but there isn't enough wind. And like a click on the turbine and find out the status survey California gives birth to the wind industry in the United States, but 16 other states, from North Dakota to Kansas, have greater potential, according to the American Wind Energy Association. Texas now ranks number two in wind production for the country.

But the association says the source remains largely untapped, providing less than one percent of U.S. electrical generation. Denmark, by contrast, gets 20 percent of its power from the wind. Linda White of the Kern Wind Energy Association, based in Tehachapi, says alternative energy sources can supplement dwindling supplies of coal, oil and natural gas, which provide most U.S. electrical generation. "As long as the wind is there, the water is there or the sun is there, we will have those renewable resources. And I think if we were to have much more of a mix or put more sustainable or alternative energy sources within our current mix, it will extend the life of those finite fuels," she said.

Government incentives in places like California are promoting the use of renewable energy sources. Ed Duggan of Oak Creek Energy Systems says, with better planning, utility companies can make more efficient use of available energy. "Maybe on a windy day, you hold the water behind the dam and save that energy for the days that the wind doesn't blow. Or maybe you keep your gas-fired peaking generator turned off on a windy day, but you run it on a day while it's a hot day when all the air conditioners are on in Los Angeles."

The industry still has work to convince Americans of the virtues of wind power. Some residents complain the large towers are unsightly, and environmentalists have criticized the windmills as dangerous to birds. This is more of a problem at another site in Northern California, which is on a migration route. In response to complaints, owners have agreed to a temporary shutdown of some of that area's wind turbines during this year's winter migration.

Michael Sullivan, VOA news, Los Angeles.
http://tran.httpcn.com/Html/1006/68658538516.shtml

Provided by:Yeqi

Welcome!

Hello!We are a group of sec 3 students from NYGH doing a physics project:wind energy.we are going to use the blog to record our progress including our research activities,meeting notes and review of reference materials.This project will last for about 3 months,and we will update the blog regularly.welcome to visit our blog when you feel free and give us your comments or discuss with us.
Whoosh~our names!yeah~We are Yeqi,Xiaolu and Peiqi!