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so…just to inform anyone who comes, i have started to collate info for part 1), the general info one.
Will greatly appreciate it if u have found any new material for (1) and wishes to post it, pls send it to my hotmail account too! 
so there.
Choir concert’s coming! invite ur friends too!
chia2.
hey all! i’ve uploaded pages (they are at the header bottom; they can be seen if you place ur mouse on top of the text beside the one ‘blog’), where we can house all our collated information for each category there (:
posted by sze yuan on 5/4/08
by the way, jenny, i found more information about wind energy being a solar energy…it’s somewhere written at the “Understanding the Wind Resource” of the article i found (:
Wind energy has been harnessed for thousands of years to perform useful work for humans. Humans have used wind power for transportation, water pumping, and grinding since the time of the ancient Egyptians. In the late 19th century, the Danes began harnessing wind to generate electricity using wind turbines.
People often use the terms windmill and wind turbine interchangeably. However, windmills harness the wind for mechanical power to grind wheat or pump water, while wind turbines use the wind to generate electricity.
Today, modern wind turbines efficiently convert the force of moving air into electricity using modern design principles and high-tech materials. Wind turbines come in many different sizes from small-scale home systems of 5 kilowatts to 15 kilowatts, to utility scale systems ranging in size from 300 kilowatts to 1,000 kilowatts. To take advantage of higher wind speeds and to allow the blades to rotate without interference, wind turbines are mounted on the top of a tower typically 160 feet high. Although there has been some experimentation with vertical-axis wind turbines, most wind turbines have airfoil-type blades that rotate around a horizontal-axis. The blades are designed like the wing of an airplane creating lift when exposed to the force of the wind, which propels the blades around in a circular motion. The wind turbine rotor typically consists of two or three blades attached to a hub. A rotating shaft from the rotor feeds into a gearbox assembly and then into the generator, which converts the mechanical motion of the shaft into electricity. As the wind changes direction, the yaw system allows the wind turbine to pivot so that the rotor spins in a plane perpendicular to the wind.
Ultimately, wind is a form of solar energy. The sun’s rays heat the Earth’s surface creating temperature differences between the land, water, and air, given their different propensities to absorb heat. This phenomena, in conjunction with the temperature differences that exist between the equator and the EarthÕs poles, creates wind as hot air rises, expands, becomes less dense, and is then replaced by denser, cooler air. In sum, wind can be thought of as the circulatory system of the planet, distributing energy from warmer areas to cooler areas. (needs more researching regarding this area still so as to confirm whether wind is a form of solar energy)
Of all the renewable energy technologies, wind power is currently the most cost competitive when compared to traditional, fossil-fuel-based energy production technologies. In fact, wind power is the fastest growing energy source around the world. The United States now has a total of 2,600 megawatts of installed wind capacity. This is equivalent to about three or four large coal-fired power plants.
Utility-scale wind farms produce electricity at about 4.5 ¢/kWh which makes wind power competitive with fossil-fuel-generated electricity. It should be noted that these economics are made possible by a federal production tax credit of 1 ¢/kWh. Even though wind is an intermittent resource, meaning wind speeds vary from day to day and month to month, wind power can be easily integrated into the existing supply mix, making a significant contribution to our nationÕs energy supply. Most analysts agree that technological improvements and economies of scale in wind turbine production will contribute to even further cost reductions in the price of wind-generated electricity.
Wind-generated electricity provides a pollution-free source of electricity. None of the harmful emissions associated with fossil fuels occur when the wind is utilized to produce electricity. Increased use of wind power in the Northeast would be a valuable step toward improving the health of the regional environment.
The main concern regarding wind energy development in the Northeast revolves around siting. Given that the best wind sites are located along mountain ridges, wind farms could alter the aesthetic character of pristine wilderness areas in northern New England and New York. On the other hand, we need to remember the serious health and environmental impacts of most other energy sources when compared to pollution-free wind power. There will always be, and should always be, places where wind development will not make sense for aesthetic reasons, but environmentally-minded citizens should seek to identify as many suitable wind sites as possible.
In the past, some people raised serious concerns about the swishing noise made by wind turbines and their impacts on migratory bird species. These concerns have largely been dealt with through technological improvements and proper siting.
article taken from: http://www.nesea.org/energy/info/wind.html
posted by sze yuan on 4/4/08
http://www.youtube.com/watch?v=QL-cRuYAxg0
This is a short clip of a Danish Wind Turbine accident. Can serve as evidence against the building of windmills, for no matter how rare these cases are, the chances exist, and thus serve as a potential harm to people who happen to be nearby. It looks pretty bad, and quote on of the commentors who watched the film:
They have been trying to stop the mill for a few days. This was not an accident that happened within seconds. Actually it was in the news in Denmark the evening before, and everybody was just waiting for the thing to collapse in the strong wind. First collapse in 30 years. Also why it got videoed…
It is up to us to debate if this is credible or not. I haven’t found information regarding the damage of windmills. Anyone?
posted by chia2 on 3/4/08
Basic concepts about wind energy…although I have one question. Is wind a form of solar energy? I tried referencing on the net but I couldn’t find much. Will check again soon.
Wind is a form of solar energy. Winds are caused by the uneven heating of the atmosphere by the sun, the irregularities of the earth’s surface, and rotation of the earth. Wind flow patterns are modified by the earth’s terrain, bodies of water, and vegetative cover. This wind flow, or motion energy, when “harvested” by modern wind turbines, can be used to generate electricity.
The terms “wind energy” or “wind power” describe the process by which the wind is used to generate mechanical power or electricity. Wind turbines convert the kinetic energy in the wind into mechanical power. This mechanical power can be used for specific tasks (such as grinding grain or pumping water) or a generator can convert this mechanical power into electricity to power homes, businesses, schools, and the like.
Wind turbines, like aircraft propeller blades, turn in the moving air and power an electric generator that supplies an electric current. Simply stated, a wind turbine is the opposite of a fan. Instead of using electricity to make wind, like a fan, wind turbines use wind to make electricity. The wind turns the blades, which spin a shaft, which connects to a generator and makes electricity.
Wind Turbine Types
Modern wind turbines fall into two basic groups; the horizontal-axis variety, like the traditional farm windmills used for pumping water, and the vertical-axis design, like the eggbeater-style Darrieus model, named after its French inventor. Most large modern wind turbines are horizontal-axis turbines.
Turbine Components
Horizontal turbine components include:
Turbine Configurations
Wind turbines are often grouped together into a single wind power plant, also known as a wind farm, and generate bulk electrical power. Electricity from these turbines is fed into a utility grid and distributed to customers, just as with conventional power plants.
Wind Turbine Size and Power Ratings
Wind turbines are available in a variety of sizes, and therefore power ratings. The largest machine has blades that span more than the length of a football field, stands 20 building stories high, and produces enough electricity to power 1,400 homes. A small home-sized wind machine has rotors between 8 and 25 feet in diameter and stands upwards of 30 feet and can supply the power needs of an all-electric home or small business. Utility-scale turbines range in size from 50 to 750 kilowatts. Single small turbines, below 50 kilowatts, are used for homes, telecommunications dishes, or water pumping.
See Wind Energy Photos page for wind farm photographs.
See Wind Energy Photos page for wind turbine photographs.
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Text and diagram from: http://windeis.anl.gov/index.cfm
I have included the links that they provided to view pictures. Enjoy!
Posted by: Jenny on 3 April 2008
Here is an introduction to renewable energy of several forms that I found online.
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From our day to day living energy has been part of it. We used energy almost in every aspect of our lives. From food preparations and storage, entertainment, maintenance, doing our jobs and earning a living, keeping us warm or cold and so on. Simply to say almost every appliances, equipments and machines in our homes and work requires energy. And as the number of households, buildings industrial and commercial, population; the need for abundunat energy is always a question. If a city or town is growing so fast will the current energy level will meet its demand? in this case an increase in energy should sustain that demand.
Where will those additional energy should come from?. The current sources of energy we have now are the coal fired powerplants, nuclear power plants and hydro electric power plants. And with the present source of energy coal and fossil power plants, the increase in air pollution rises rapidly. As for nuclear power plants the danger of a melt down. However there are safe sources of energy. These are renewable energy, which are gifts from nature. Generally renewable energy are sources of energy which naturally occurs and are abundant in nature.
There are several types of renewable Energy
Solar Energy – This comes from the light from the sun. Depending on the type of process used the sunlight can be converted into electricity.
Wind Energy – To take advantage of this energy man created wind mills and turbines that converts wind into electricity.
Geothermal Energy – This form of energy utilizes the heat fromm earth itself
Other renewable energy sources are tidal power from seas and oceans, and biomass from garbage
With the increased demand in energy, thus the need for supply should increase but it does not mean that we should neglect consequences to nature. Because of the increased pollutants in the air the harm of global warming is taking effect. If we are looking for additional sources of energy we should look for a safe a pollutant free as possible source of energy should be utilized. Not only that we must now start eradicating those energy sources which greatly harms our ecosystem.
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Taken from: http://www.atlantic-renewable.com/
Posted by: Jenny on 3 April 2008
I see I am the last to post. Oh well. Anyway, here is some information about wind energy and its applications. I shall refrain from repeating what Cynthia has posted.
Wind energy converts kinetic energy that is present in the wind into more useful forms of energy such as mechanical energy or electricity. Wind energy is a pollution-free, infinitely sustainable form of energy. It doesn’t use fuel; it doesn’t produce greenhouse gasses, and it doesn’t produce toxic or radioactive waste.
Windmills that were used to grind grain are an example of early uses of wind energy. Modern uses of wind energy include generation of electricity and pumping water. Current wind energy machines are called “wind turbine generators“, “wind pumps”, or more generally, “wind turbines“.
Humans have used wind energy for thousands of years. Ancient Persians used wind energy to pump water before the birth of Christ. The world was explored by wind-driven ships long before engines were invented. As recently as the 1920s, over a million wind turbines pumped water and provided electricity to farms in North America. As said above, windmills used to grind grain is also an example of early uses of wind energy, and perhaps one that is closer to our time.
The current interest in wind energy was started by the need to develop clean, sustainable energy systems that can be relied on for the long-term future. Modern aerodynamics and engineering have improved wind turbines. They now provide reliable, cost-effective, pollution-free energy for individual, community, and national applications.
Wind energy is the kinetic energy that is present in moving air. The amount of potential energy depends mainly on wind speed, but is also affected slightly by the density of the air, which is determined by the air temperature, barometric pressure, and altitude.
For any wind turbine, the power and energy output increases dramatically as the wind speed increases. Therefore, the most cost-effective wind turbines are located in the windiest areas. Wind speed is affected by the local terrain and increases with height above the ground, so wind turbines are usually mounted on tall towers.
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The information is gotten from the homepage of The Canadian Renewable Energy Network (CanREN), created through the efforts of Natural Resources Canada (NRCan) and its stakeholders. Its purpose is to increase the understanding of renewable energy to accelerate the development and commercialization of renewable energy technologies.
CanREN promotes what NRCan and its partners are doing to advance the role of renewable energy in Canadian society. It offers general information on renewable energy sources, highlights the technologies and applications being developed to harness these sources, and presents Canadians with the knowledge and support they need to make renewable energy part of their everyday lives.
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There. I shall post up to here today. Credits to http://www.canren.gc.ca/ for the wonderful information.
Posted by: Jenny
Who winded up the last one to post on: 2 April 2008
voices of the winds