SOLAR WITH LESS WATER

Understanding Solar Power in Arizona
Senator Jon Kyl, June 7, 2010 (National Ledger)

"With its 300-plus days of sunshine annually, Arizona would seem a perfect place to produce solar power. Elected officials and solar developers alike are touting [it and]… claiming it will create hundreds of thousands of "green" jobs and replace energy production using fossil fuels…[F]ederal and state governments have enacted policies to accelerate the deployment of solar energy in Arizona….

"The reality, however, is not that simple. While Arizona enjoys abundant sunshine, it is also burdened with limited water resources. Conventional concentrating solar power (CSP), the solar technology of choice for utility-scale solar-power generation, requires billions of gallons of water to produce electricity…I recently prepared a report about the potential water-energy crisis in Arizona…"

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"Nearly all of the current federal applications for solar projects in Arizona call for conventional CSP, and at least one of these projects is being "fast-tracked" through the environmental-review process…These projects will have long lives - at least 30 years - so it's necessary that we account for their impact on our state's water supply…Arizona has yet to [\force its solar developers to use less water-intensive technologies or wastewater] and must consider doing so.

"Arizona, however, can still be the solar capital of the world if we focus on more responsible solar technologies that use far less water and develop advanced utility-scale technologies that will be cost-competitive with fossil fuels. Some companies are already deploying CSP in California and Nevada using a "dry-cooling" process…but, unfortunately, the U.S. Department of Energy has yet to recognize or provide the critical support needed to help make these alternatives a reality."

The numbers. (click to enlarge)

"Rushing to deploy conventional CSP will have unintended consequences that its proponents may regret…While it's true that Arizona's sunny climate is ideal for solar-energy production, its arid landscape poses significant challenges to the deployment of solar systems that rely more heavily on water than other forms of energy production.

"The water-consumption requirements of current solar-energy production could put considerable additional strain on Arizona's already limited water supply…State and federal policymakers should ensure that energy policy takes these factors into account in order to protect Arizona's limited water supplies."