WIND
ENERGY

While we’ve been harvesting energy from wind for several decades, it is only in the last few years — as the world has become more concerned about global climate change — that we’ve increased installation of wind turbines to the point where wind has become a noticeable contributor to our energy mix. In 2010, installed wind capacity reached 197 gigawatts (GW) and produced about 2.5% of the world’s electricity.

Wind is on the cusp of becoming a major source of electricity around the world. Wind is widely available around the world (see the USA wind map on left (click to enlarge), and its recent rapid growth is expected to continue, since it is already the cheapest or one of the cheapest sources for new electricity all around the world and its costs are projected to keep falling.

How do residential wind turbines work? The wind turbine typically stands on a high tower in order to catch the prevailing wind. In a typical installation the home is still connected to the local power grid and combined with a solar system, so that when the winds are slow, and at night the homeowner will purchase power from the utility. But when the wind is blowing, the wind turbine and solar system can produce enough wind power to not only light up a house, but to also sell some electricity back to the power company. A wind power system or a solar system in a remote location does not have a grid, so it will need batteries in order to store the extra power.