Portfolio heat: Three plays on geothermal

'Geothermal energy, or heat generated from the earth, is largely non-polluting, and is renewable and reliable," says Ashley Winters and John Parke.

In Stephen Leeb's The Complete Investor, the contributing editors look at a trio of diverse plays on geothermal energy:  Chevron (NYSE: CVX), Calpine (NYSE: CPN), and Ormat Technologies (NYSE: ORA). 

"Throughout the globe, heat is continually produced in a layer far below the earth’s crust. Large power plants can capture and use this steam to provide electricity on a fairly large scale.

"In Iceland, by some estimates, 50% of all energy needs are met through an alternative energy source that has been known for a long time, 

"Geothermal is used in many other places as well. The largest system in operation is in California just north of San Francisco, in an area known as the Geysers.

"Efforts are also underway to use geothermal