Ivanpah Solar Electric Generating System in California officially opened in February 2014 after four years of construction. Visit the location link in Google Maps. It consists of three towers and thousands of surrounding mirrors. They stand near the Mojave National Preserve and the Nevada border, 65 kilometers from Las Vegas along Interstate 15. All photos are by Gilles Mingasson/Getty Images.
The operating principle is simple. Mirrors follow the sun and reflect light to the top of each tower. The collective heat generates steam which in turn spins a turbine that produces electricity distributed on the grid. What is not simple is the sheer immensity and scale.
The plant sits within Ivanpah Dry Lake on 3,500 acres of public land. The location receives 330 – 350 sunny days each year. The three power units generate 377 megawatts of electricity. That is enough to power 140,000 homes. Smaller similar systems are in Spain and China.
This closer view shows a thermal tower illuminated a small amount at the top by reflections from a few mirrors. A total of 170,000 heliostats are spread out over 13 square kilometers. That is 5 square miles. Each heliostat is a steerable pair of flat mirrors.
They are mounted on slender posts inserted into the desert floor so as to cause the least disruption to the ecology.
Here are a few more views of the mirrors. The first image is of some ready to be mounted in the array around the tower.
When the mirrors are aligned to point the reflection of sunlight onto the 460 ft. tall tower, they raise the temperature of the water in the closed loop piping to 1000˚F. The super heated steam drives the turbines to make electricity. As you can see in this image, only some of the mirrors are aligned during this testing phase.
According to the owners and proponents, this power system will reduce carbon dioxide emissions by 400,000 tons per year compared to the same energy output by conventional generating systems. The owners are NRG Energy, Inc., BrightSource Energy, Inc. and Google. Construction is managed by Bechtel.
More images are available at this Flickr site.
Several virtual 360˚ tours are available at this site. On-screen controls let you move around and zoom your view.
The Ivanpah promotional site is here.
The BrightSource site is here.