home > customer service > Frequently Ask Questions1. How do you choose a site for a potential wind farm?
A lot of work goes into finding the right site for a potential wind farm. There are many factors to consider,such as: the availability of wind ，access to the electricity grid,current land use,environmental impacts.
2. How strong does the wind have to blow for the wind turbines to work?
Wind turbines start operating at wind speeds of 4 to 5 metres per second (around 10 miles an hour) and reach maximum power output at around 15 meters/second (around 33 miles per hour). At very high wind speeds,i.e. gale force winds,(25 metres/second,50+ miles/hour) wind turbines shut down automatically to protect their structural integrity.
3. How efficient are wind turbines?
The theoretical maximum energy which a wind turbine can extract from the wind impinging upon it is around 60 per cent. However the meaning of efficiency is different with wind energy,where the fuel is free. The primary concern is not the efficiency for its own sake,but to improve productivity in order to bring the price of wind energy down.
4. How long does it take for a turbine to pay back the energy used to manufacture it?
The comparison of energy used in manufacture with the energy produced by a power station is known as the energy balance. It can be expressed in terms of energy pay back time,i.e. as the time needed to generate the equivalent amount of energy used in manufacturing the wind turbine or power station. According to the British Wind Energy Association,the average wind farm in the UK will pay back the energy used in its manufacture within three to five months,this compares favourably with coal or nuclear power stations,which take about six months.
5. Isnt it cheaper to save electricity?
It is usually cheaper to save electricity than to generate it,by whatever method. The latest information on how much it costs to save electricity is available from the Energy Savings Trust. However,to combat climate change,the UK will need a mix of both renewable energy technologies and energy efficiency measures. You can help by turning off electrical appliances once they have finished their cycle – and the standby button on your television.
6. What happens when the wind stops blowing?
When the wind stops blowing,there will be a commensurate increase in electricity injected into the National Grid from conventional sources of generation: coal,gas and nuclear. It will be possible for up to 10 per cent of the countrys needs to be met by intermittent energy sources such as wind energy,without having to make any significant changes to the way the system operates. More can be accommodated,but extra storage capacity or spinning reserve would be necessary,which would have a cost implication.
7. Are wind farms noisy?
Modern wind turbines make relatively little noise. The level of sound can vary considerably depending on the shape of the land,the position of the listener and the speed of the wind. In most instances,it is possible to carry on a conversation at the base of a wind turbine without having to raise your voice.
8. Do wind farms affect tourism?
Yes,some wind farms have had a positive effect on tourism. For example,Pacific Hydro’s Codrington Wind Farm in southwest Victoria,attracts 50,000 visitors each year through its successful tour operator business.
9. Do wind turbines frighten livestock?
Wind farming is popular with farmers because their land can continue to be used for growing crops or grazing livestock. Sheep,cows and horses are not disturbed by wind turbines. The first wind farm built in the UK,Delabole in Cornwall,has a stud farm and riding school on site and the farmer,Peter Edwards,often rides around the wind farm on his horse.