The Ivanpah solar tower, formally known as the Ivanpah Solar Electric Generating System, is the largest solar thermal power facility currently under construction.

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Solar energy speculators want to build a solar tower facility in Arizona that would be more than three times the height of the Eiffel Tower.

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The water host also means they can be mounted low to the ground, kept cool on hot days, and easily withstand weather events that could topple a tall solar tower.

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In October, the solar-tower developers signed a power purchase agreement for the first La Paz facility.

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Among those projects is the Brightsource Ivanpah project, a 450-foot-fall solar power tower located in the Mojave Desert.

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Ivanpah is a solar concentrator project, using fields of mirrors, known as heliostats, to concentrate sunlight onto a solar receiver on top of a tower. (This project when finished will include 173, 000 heliostats.) The concentrated sunlight is used to heat water, generating steam which is used to turn a traditional turbine and generator to produce electricity.

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Known as a downdraft tower, the project by Solar Wind Energy, Inc.

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Solar Wind Energy (which used to be called Clean Wind Energy Tower, Inc.) is negotiating for a lease from the Bureau of Land Management (BLM) for a 1, 700-acre parcel of flat, empty desert on the Mexican border, right next to an Air Force bombing range.

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