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Economics:
Technical Stuff:
Environmental Questions:
Windfarm Development:
How much electricity can wind energy produce?
The European Wind Energy Association (EWEA) released a report not so long ago forecasting that wind power has the potential to supply 12 per cent of the world's electricity by 2020.
We’re already on the way. By the end of 2005 there were 59,322 megawatts (MW) of installed wind capacity worldwide generating enough clean electricity for the equivalent of 18 million homes. Over the past decade the installed generation capacity for wind energy has increased at an average rate of 30% per annum.
Source: Source: BTM Consult ApS, March 2006, www.btm.dk
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Does wind energy create jobs?
Yes, it does and it’s a growth industry. The business of producing energy from wind is huge, already turning over $A13 billion. In 2003 it employed an estimated 100,000 people. By 2020, the wind energy industry is expected to employ 1.8 million people and be worth $A120 billion a year.
The emerging Australian wind industry could create thousands of jobs. It is already delivering hundreds of new jobs in Victorian and Tasmanian manufacturing facilities and many more direct and indirect jobs in transport, installation, operations and management.
Sources: European Wind Energy Association www.ewea.org; Australian Wind Energy Association www.auswea.com.au
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How much does wind energy cost?
According to a recent AusWEA report, the price of wind power in Australia will be competitive with that of fossil fuels before 2020 if the uptake of wind energy continues to grow at current rates. The price of wind energy has already fallen more than 75 per cent over the last 25 years. Economies of scale and technical refinements are expected to deliver further price reductions of 5 per cent a year.
Source: Cost Convergence of Wind Power and Conventional Generation in Australia published at www.auswea.com.au
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Is wind energy used in Australia?
The Australian wind industry has some of the finest wind resources in the world. There is now the potential to generate enough clean electricity to power two in five Australian homes.
In the last five years, wind energy has grown 400 per cent. In early 2006 there was 708MW of total installed capacity. Projects capable of providing another 1,5000MW were either approved or under construction.
The Australian Greenhouse Office has forecast, in a recent review, that wind energy will capture 41 per cent of the market of new renewable energy projects by 2020.
Source: AusWEA www.auswea.com.au
Source: A Review of the Operation of the Renewable Energy (Electricity) Act 2000, published at www.mretreview.gov.au
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What is the Mandatory Renewable Energy Target?
In April 2001, the Federal Government introduced a target designed to increase by 2 per cent (or 9,500 gigawatt hours), the share of renewable energy in Australia’s energy mix by 2010. This was called the Mandatory Renewable Energy Target, or MRET.
Under the MRET, wholesale purchasers of electricity (mainly electricity retailers) must purchase an increasing amount of their electricity from renewable sources (e.g. wind, hydro, solar, etc.), so that Australia becomes less reliant on non-renewable and polluting energy sources.
Source: Office of the Renewable Energy Regulator www.orer.gov.au
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What is the Victorian Renewable Energy Target?
Victoria recently introduced the VRET to increase renewable energy’s market share from the current level of 3 per cent to 10 per cent by 2016.
Like the MRET, the Victorian scheme requires wholesale purchasers of electricity (mainly electricity retailers) to source an increasing amount of their electricity from renewable sources. Other states, including New South Wales and South Australia have announced plans to introduce their own renewable energy schemes.
Source: Essential Services Commission www.esc.vic.gov.au
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What is wind?
This might surprise you but wind is actually an indirect form of solar energy.
Wind is created by the movement of air, due to the heating and cooling of air parcels by the sun.
As air is heated it becomes less dense and rises, creating an area of low pressure. This then causes air from neighbouring areas to move, traveling in the direction of the low pressure, creating winds.
Surface winds occur close to the earth’s surface and are affected by the shape of the land and sea, which is why some areas are more windy than others.
In coastal areas, the air on the land heats faster than the sea, which can create a sea breeze – a wind that travels from the sea to the shore.
At night, the land cools down faster than the sea, so the wind changes direction, now traveling out to sea.
In mountain areas, as the air on the slopes is heated, it rises to the top of the mountains. At night, the wind direction is reversed and becomes a down-slope wind.
Wind directions are important when Pacific Hydro is deciding where to place wind generators, since we want to place our windmills in the areas that have the least obstacles from the natural wind directions.
Source: Danish Wind Industry Association www.windpower.org
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Is there enough wind?
Absolutely. If we properly harnessed the world’s wind, there is enough wind energy spread around the globe to meet the whole world’s electricity needs more than 4 times over. Less than 0.1 per cent of the global wind resource is currently being used. Plus, unlike fossil fuels, wind energy will never run out.
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How does a windmill make electricity?
Wind generator blades are modeled after airplane wings. They’re designed so that they rotate because of a pressure differential, caused by air moving over the surface of the blade. The blades cause a rotor to turn, which then drives an electrical generator.
The windmills installed at Pacific Hydro’s wind farms are ‘smart machines’ – able to operate without intervention. Each windmill uses its own internal computer system to monitor the direction and speed of the wind, with electricity production commencing automatically at wind speeds above 14 km/h.
The amount of electricity produced continues to increase with the wind speed until the wind generators reach their maximum or ‘rated’ capacity at winds of around 55 km/h.
With blades rotating slowly at 17 revolutions per minute, the wind generators continue to operate at their maximum output until the wind speed reaches 90 km/h, at which point the windmills automatically shut down and turn out of the wind to avoid being damaged.
However, winds of that speed are not very common. In fact, only one windmill needed to shut down at Challicum Hills in the development’s first eight months of operation.
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Can a wind farm be installed anywhere?
No. Finding the right site for a wind farm takes a lot of work, and Pacific Hydro works closely with landholders and local communities to identify and then check the perfect site is available.
The windmills need very careful placement.
How’s your maths? The energy content of the wind can be calculated by working out the cube (the third power) of the wind speed. Twice as much wind yields 8 times the energy (i.e. 23 = 2 x 2 x 2 = 8).
The short answer is that wind farm developers aim to place windmills in the most windy areas they can find.
The roughness of the terrain (including the terrain surface, its contours, and the presence of buildings, trees, plants, and bushes) affects the local wind speed. Very rough terrain, or nearby large obstacles, may create turbulence, which decreases energy production and increases wear and tear on the generators.
Predicting the annual energy production from a windmill is quite a complex task. It requires detailed maps of the area and accurate meteorological wind measurements for at least one year before the site can be confirmed as suitable.
Source: Danish Wind Industry Association www.windpower.org
Codrington Wind Farm layout
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Are windmills producing electricity 24 hours a day?
Almost. A typical wind farm generates electricity between 90 to 95 per cent of the time.
Source: AusWEA www.auswea.com.au
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How much electricity can one wind generator produce?
Each windmill installed at Pacific Hydro’s Challicum Hills Wind Farm produces enough clean electricity to meet the annual needs of more than 800 Victorian households.
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Is there any progress in windmill technology?
The latest technology is continuously introduced into new wind generators. A modern wind generator produces more than 100 times the annual output of a 1980 vintage generator.
Source: World Wind Energy Association www.wwindea.org
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Where does electricity come from?
More than 90 per cent of our electricity comes from highly polluting fossil fuels. Not only do they pollute the Earth, damaging the environment, but they are running out, so new ways of generating electricity are required.
Source: Electricity Supply Association of Australia 2003
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Where could electricity come from?
Did you know that, according to a recent study, there are enough resources of “clean energy” like wind, solar, and bioenergy, to make up 70 per cent of our required electricity supply by 2040? That would cut Australia’s greenhouse gas emissions by half.
Source: A Clean Energy Future for Australia, BCSE, March 2004
* About 13 per cent is natural gas and about 2 per cent is biomass
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Why are we building wind farms?
Scientists around the world agree that climate change is the biggest environmental threat facing the world today. Essentially, increased levels of greenhouse gas emissions in the atmosphere are causing this climate change problem.
This is an issue already affecting our world. With 10 out of the last 14 years being the warmest on record, we urgently need to take effective action for reducing greenhouse gas emissions.
Some of the impacts of serious global warming in Australia could include:
- More frequent and severe droughts and storms,
- The destruction of the Great Barrier Reef,
- An end to ski-able snowfields in the highlands,
- Mass species extinction, and
- The spread of tropical illnesses.
Wind energy is already playing a central role in helping to reduce the impacts of climate change for future generations.
Source: Climate change – An Australian Guide to the Science and Potential Impacts, Australian Greenhouse Office 2003 published at www.greenhouse.gov.au
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How do wind farms avoid pollution if we need to use other power stations when the wind doesn't blow?
Wind farms avoid greenhouse pollution in a similar way to energy conservation.
If you turn off an electrical appliance, such as a light or an air conditioner, you reduce demand for electricity generation. The more that people conserve electricity, the less fossil fuels will be burnt, which is good for the environment.
Similarly, when the wind blows, pollution-free electricity is fed into the national electricity grid, reducing the demand for fossil fuel generation. Every time a household uses renewable energy, it is not using fossil fuel.
Our windmills work hard. On average, a single windmill can provide enough pollution free energy to supply the annual energy needs of 800 homes. So the more windmills we build, the more we can reduce our reliance and demand for fossil fuel energy.
Wind energy production does fluctuate but that does not mean your lights will go out when the wind stops blowing.
All electricity systems in the world are structured to react quickly to fluctuations in electricity demand as people turn electrical appliances on and off. The same systems can be used to deal with the situation when the wind stops blowing to ensure a constant, reliable power source is always available.
The only difference is the major one - a reduction in greenhouse pollution as we build more wind farms.
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How long does it take for a wind farm to payback the energy used to make it?
A modern wind farm pays back the energy used in its manufacture and construction in just 3 months. Over its 25-year life, a windmill will produce more than 100 times the energy required to make and install it.
Source: A Clean Energy Future for Australia published at www.wwf.org.au
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Do wind farms harm wild life?
Studies from Canada, Denmark and the US have shown that the total impact on native wild life from wind farms is negligible compared to the impact from road traffic.
Australian wind farms are required to undertake detailed flora and fauna studies during their planning process to ensure they will not threaten any species.
The release of two landmark surveys into the impact of Victoria's wind farms on birds and bats in 2004 revealed an average of 1 to 2 collisions per generator per year and there were no rare, threatened or endangered birds or bats killed at the surveyed wind farms. In comparison to the risks posed by power lines, cars and, most importantly, global warming, the risks from wind farms to birds and bats is minimal. Also, wind farming is popular with farmers, because their land can continue to be used for growing crops or grazing livestock.
Sources: American Wind Energy Association www.awea.org; Danish Wind Industry Association www.windpower.org Environment Victoria www.envict.org.au
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Are wind generators noisy?
A wind generator is made up of moving parts and therefore does make some noise – such as the hum of the generator and the whoosh of the blades passing the tower.
But, thanks to advances in technology, well designed, appropriately sited windmills are quiet enough to cause no disturbance to people living just a few hundred metres away. You are able to carry out a normal conversation while standing underneath a modern windmill.
The maximum noise level from a wind farm at any surrounding dwelling in Victoria is 40 decibels (about the same noise level as a library), or 5 decibels above a usual level of existing background noise, whichever is louder.
And that’s the worst case scenario. Depending on local weather conditions, the noise level will usually be much lower or non-existent.
People react differently to noise – the best way to learn more about noise levels is to visit one of Pacific Hydro’s wind farms and listen for yourself.
Source: www.yes2wind.com
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Is wind energy popular?
Absolutely. Wind energy enjoys wide popular support both in Australia and around the world.
A 2002 Auspoll survey found 95 per cent of Victorians support wind farms with 86 per cent preferring wind energy to new gas or coal-fired power stations.
A 2003 national survey also found 95 per cent of the population support wind farms.
Source: National survey published at www.auswea.com.au
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Do wind farms affect tourism?
Yes, wind farms are tourist attractions, which is great news for local businesses.
Codrington Wind Farm in southwest Victoria attracts 50,000 visitors a year. It also supports a successful tour operator business, and enhances the local economy.
Source: Pacific Hydro www.pacifichydro.com.au
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Can I visit a wind farm?
Guided tours of Pacific Hydro’s Codrington Wind Farm can be booked through local operators.
To book a tour of Codrington Wind Farm (near Port Fairy) call 03 5568 1853.
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Do wind generators take up much land?
Windmills and access roads occupy around 1-2 per cent of the land area in a typical wind farm site, leaving farmers free to grow crops or graze livestock.
Source: AusWEA www.auswea.com.au
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Is the landscape affected after a windmill has been dismantled?
Restoring the surrounding landscape near to its original state after the useful life of the wind farm has become a routine task for developers.
Source: AusWEA www.auswea.com.au
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How can I buy wind energy for my home?
Once we have created electricity through our wind farms, we sell it to a power company. Therefore, to ensure that your home is receiving wind power, you need to check that your electricity company is trading in clean energy as well as the usual non-renewable power sources.
The electricity from both the Codrington and Challicum Hills wind farms is retailed by Origin Energy, which includes it as part of their Green Earth product.
For more information, contact Origin on 13 21 14.
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What makes a good wind farm site?
Pacific Hydro looks for many essential elements when choosing a site for a wind farm, including:
- Strong and consistent winds
- Close connection into the National Electricity Grid
- Compatible land use
- Large land area for optimum spacing of wind generators
- Accessibility for construction vehicles and machinery
- Supportive landholders and local community.
By the way, this long list of essential criteria rules out most of the coastline and many inland sites.
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What are the main steps in developing a wind farm?
Pacific Hydro only develops wind farms which are appropriately-sited, well-designed and locally supported.
A typical wind farm takes around 3 to 5 years to develop from the installation of the wind monitoring mast through to first electricity generation.
The main steps in development are shown below.
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