Wind Power

Wind is considered an indirect form of solar energy, because wind is created by the atmospheric temperature differences caused by the heat from sun, the rotation from the earth, and the earth's surface irregularities.

Wind energy systems use wind to turn aerodynamic blades attached to an electric generator or turbine. Turning blades drive a generator which produces electricity. Power capacity of wind turbines range from 250 to 2,000,000 watts (2MW). (i.e 600,000 watts provides power to 200 households). 

Advantages

• Renewable and clean energy source, using energy already present in the atmosphere

• Does not produce emissions

• Less expensive than other renewable forms of energy

• Wind energy is competitive if the full costs of conventional and nuclear power plants are taken into account (environmental, health, direct & indirect subsidies). Wind energy costs are decreasing as technology develops and its scale increases.

• Benefit the economy in rural areas

• Land can be used for other purposes, i.e. agriculture and farming.

• Wind's long term potential could exceed current energy consumption

• Solar energy can counter balance wind energy's fluctuating supplies, as it tends to be windier at night and during stormy weather, and more sunny when there is less wind.

• do not require water, unlike fossil & nuclear power stations, which need large amounts of water for cooling

• studies suggest that the number of birds killed by wind turbines is negligible compared to other human activities, such as environmental impacts from using conventional power sources, traffic, hunting, power lines and high rise buildings. In the UK, the Royal Society for the Protection of Birds support wind farms. It notes that climate change poses greater threat to wildlife and appropriately positioned wind farms do not pose a significant hazard for birds.

• According to British Wind Energy Association, less than 1% of the land would be used for foundations and access roads, the other 99% could still be used for farming. (it is common for farmers to lease out their lands)

• Improvements in blade design and gearing have decreased the noise.

• Aesthetic concerns can be reduced by careful positioning of  turbines (i.e. along the motorway).

Disadvantages:

• The intermittent nature of the wind reduces the load factor for wind facilities (This could be addressed by grid energy storage facilities. Power would be more constant if a number of wind farms were spread over a wide area and girded together).

• High initial cost, maintenance can also be expensive

• High quantity of turbines would need to be built to meet energy demands.

• Good wind sites are often situated far from the demand areas

• Concern over noise & visual impact

• Ecological footprint in the areas with no previous development

• Windmills kill birds and bats, and more research is needed to take into account of the bird migration paths and bat site locations.

Wind Turbines