Nuclear Energy

The US has the highest installed wind power capacity in the world (36.3 GW), followed by
China (33.8 GW) and Germany (26.4 GW), as of June 2010. China is presently the locomotive of
the international wind industry, adding 13,800 MW within one year in 2009, more than doubling its
wind power capacity for the fourth year in a row. Several countries have achieved relatively high
levels of wind power penetration; wind power was 20% of stationary electricity production in
Denmark, 14% in Ireland and Portugal, 11% in Spain, and 8% in Germany in 2009. dcliv
The rise in global wind energy capacity has been accompanied by a sharp fall in costs: wind
energy today costs only about one-sixth as it did in the 1980s, dropping from about 25 cents/kWh in
1981 to an average of about 4 cents/kWh in 2008 – a price that is competitive with new coal- or
gas-fired power plants (figures are for the USA). With costs expected to further decline in the
coming years, and growing concerns about the environmental costs of conventional sources of
energy, wind power is expected to exponentially grow in the coming years. dclv The Global Wind
Energy Council projects global wind capacity will reach 332 GW by 2013, more than double its
current size. dclvi While wind power now contributes 1.3% of the global electricity supply, this is
projected to increase to 8% by 2018. dclvii
The variability problem with wind power
The most important question raised about the potential of wind energy is its variability, as
variation in wind speed results in variation in power generated. However, electric power generation
companies know how to deal with this problem. Even with electric power from conventional
sources of energy, electric power companies need to constantly adjust to constant changes in
electricity demand, turning power plants on and off, and varying their output second-by-second as
power use rises and falls. They also need to meet unexpected surges or drops in demand, as well as
power plant and transmission line outages. Therefore, they know how to deal with changes in wind
power generation at different wind turbines. In addition, the wind is always blowing somewhere, so
distributing wind turbines across a broad geographic area helps smooth out the variability of the
resource.
This is also being proved in practice. In the US, which installed a record 8,500 MW of wind
power in 2008, capable of producing enough electricity to power more than 2 million typical
homes, many electric power companies are already demonstrating that wind can make a significant
contribution to their electric supply without reliability problems. Xcel Energy, which serves nearly
3.5 million customers across eight states, currently obtains eight percent of its electricity from wind
and plans to increase that to about 20 percent by 2020. There are also several areas in Europe
where wind power already supplies more than 20 percent of the electricity with no adverse effects
on system reliability. Three states in Germany in fact have wind electricity penetrations of at least
40 percent. dclviii
159