February 22, 2008 Plans have been unveiled for a whopping 280 megawatt (MW) concentrating solar power facility in Phoenix, Arizona, making it one of the world’s largest. The Solana Generating Station, to be run by Arizona Public Service (APS), will produce enough energy to serve 70,000 customers when operating at full capacity.
Spanish for “sunny place,” Solana will not emit greenhouse gases and will provide APS with more solar electricity per customer than any utility in the U.S. The plant will be built by Abengoa Solar, and is scheduled to provide renewable energy beginning in 2011.
Unlike conventional solar-photovoltaic plants, which produce electricity directly from sunlight, concentrating solar power uses the sun’s heat to boil water and drive turbines similar to those found in coal power stations.
Parabolic mirrors track the sun and focus solar energy on a heat transfer fluid (elsewhere Fresnel reflectors are being developed for this purpose). Once heated, the liquid converts water into steam, which turns the plant’s turbines to create electricity. Because energy is both produced and stored during the day, energy can be provided across periods of peak demand.
APS will purchase 100 percent of the plant’s energy output, pending approval from the Arizona Corporation Commission. The value of the produced energy will be about $4 billion over 30 years. According to APS President Don Brandt, the Phoenix location was chosen as “APS is committed to making Arizona the solar capital of the world and bringing affordable renewable energy to all our customers.” APS already provides its customers with 131.5 MW of renewable energy, enough to power more than 37,000 homes and within the last 90 days has announced two new major solar projects. The Solana plant will create about 1,500 construction jobs and, when completed, will employ about 85 highly-skilled technicians. APS and Abengoa Solar estimate the project will bring more than $1 billion in economic benefits to the state of Arizona.
If operating today, Solana Generating Station would be the world’s largest solar power plant and large scale solar is becoming big business in the US with Nevada and California making plans to build 100MW and 500MW plants respectively within the next four years. Australia also has plans for a large scale solar concentrator station with a 154MW facility powering more than 45,000 homes to be built in the State of Victoria. However, current plants generally range from 5-15MW. This shows that the Solana plant is truly "green" power on a massive scale. But how does this plant measure up with traditional coal and nuclear plants? The average coal plant has an output of anywhere from 1000-5000MW and the average nuclear plant from 600-1200MW. So while solar is still lagging behind, making the jump from 5MW facilities to 280MW or even 500MW is a big step in the right direction for large scale renewable energy production.
