The world’s largest solar thermal power plant

May 28, 2012 | Source: Technology Review

The Ivanpah, Nevada solar thermal plant uses concentric circles of mirrors that will focus sunlight onto a central tower, generating high temperatures to produce steam. The plant will feature three towers, each with its own set of mirrors. The first unit, in the foreground, is the nearest to completion. By February of this year, workers had begun to install mirrors, which can be seen in the upper left and right sides of the field. (Credit: Brightsource)

The outlines of a massive solar thermal power plant — the largest ever — are starting to appear in the wilderness outside of Las Vegas. The $2.2 billion project, being built by Oakland, California-based Brightsource, stretches over 3,600 acres near Ivanpah, California. When it’s finished, it will generate 370 megawatts of electricity on sunny days.

But the future of solar thermal power plants is in doubt. That’s in large part because prices for solar panels — which convert sunlight to electricity directly — have dropped quickly in the last few years, causing at least one company to abandon plans to build solar thermal plants in favor of making ones that use solar panels.

Yet solar thermal has at least one great strength: the heat it produces is easy to store, so electricity can be generated even after the sun goes down, and power can be dispatched to the grid whenever it’s most needed.

However, Las Vegas uses 5,600 megawatts on a summer day, as of 2007, according to Forbes. By 2015 that’s expected to hit 8,000.