Google continues its investment in renewable, clean energy with $168 million for the Ivanpah Solar Electric Generating System in California. This follows on $20 million it put in CoolPlanetBiofuels a week before.
Ivanpah, which is already under construction, will be the largest solar power tower facility in the world, producing 392 MW of power (1 MW is approximately enough for 650 homes, so Ivanpah will have the capacity to power about 255,000 homes). It is located in the Mojave Desert. Unlike traditional photo-voltaic solar energy in which the heat of the sun is converted directly to electricity, solar power tower technology uses thousands of heliostats to focus the sun’s rays on a central tower. The tremendous heat is used to create steam which powers turbines to create electricity.
Some solar power towers (this is also known as solar thermal) stores the heat in molten salt rather than creating steam directly. Salt retains heat for long periods of time; hence, such facilities can create power at night too. Ivanpah doesn’t store heat but instead relies on natural gas to power the turbines when needed.
Wait, you say, but this uses water in a desert, and that can’t be good. Yes, it does use water. However, it tries to minimize water use by using air-cooled condensers to turn the steam back into water. Ivanpah, when completed, will consist of three plants with three solar towers each. Total water usage for all three plants is estimated to be 100 acre feet per year. One acre foot is about 325,000 gallons.
Virtually all types of power generation use water, often in huge quantities. The Union of Concerned Scientists says a typical 500 MW coal plant uses 2.2 billion gallons of water a year. Nuclear power uses even more. Ivanpah by contrast will use 32.5 million gallons of water a year, this for a plant only 20% smaller than that typical coal facility. Clearly, this is vastly more environmentally friendly than coal or nuclear.
Construction began late last year, yet the California Energy Commission accepted the application three years previously. The ponderous process of getting all the requisite permits in California takes much too long. We need a streamlined process so that big construction projects can get a yes or no within a few months, not a few years.
Many more such solar power projects are planned for California. We will have many gigawatts of clean renewable energy within a few years, as well as many new jobs for Californians.