Photos: Harnessing the wind

Wind turbines like this one in Dorchester, Mass. provide significant amounts of energy using only the natural power of the wind. Considered a renewable energy, wind doesn't use a material fuel like coal, natural gas, or oil.

Construction on the Dorchester, Mass., turbine began in May. The structure is located on the property of International Brotherhood of Electrical Workers Local 103, which received a $260,000 grant from the Massachusetts Technology Collaborative for the project. The wind turbine project cost $540,000 and supplies energy to the union's apprentice-training facility. IBEW Local 103 installed solar panels on the facility in November 2002.

The Dorchester wind turbine came from Germany. In most turbines, three lightweight blades spin around a horizontal axis as air flows over them, rotating faster as wind speeds increase. Within the nacelle located at the top of the turbine, behind the blades, the spinning motion is converted from rotational energy into electricity.