A 110-megawatt solar thermal plant located near Tonopah, Nevada.
Reuben Wu © 2016

The Crescent Dunes Solar Energy Project is a 110-megawatt solar thermal plant located near Tonopah, Nevada. It also is a molten salt storage plant, capable of holding 1.1 billion kilowatt-hours of energy. 10,347 heliostats circle a 640-foot tower at the center and have a combined surface area of 1.28 million square feet. The $1 billion plant produces electricity at 13.5 cents per kilowatt-hour, higher than wind and solar farms to be sure. However, Tonopah provides steady baseload power, which in turn enables intermittent energy from renewable wind and solar to be seamlessly integrated into the grid.

Concentrated Solar Power

Reduce SourcesElectricityShift Production
CO2 Equivalent
Reduced / Sequestered
Billion $US
Net First Cost
(To Implement Solution)
Trillion $US
Lifetime Net
Operational Savings
Concentrated solar power uses sunlight as a heat source. Arrays of mirrors concentrate incoming rays onto a receiver, to heat fluid, produce steam, and turn turbines.

Solution Summary*

Concentrated solar power (CSP), also known as solar thermal electricity, has been around since the 1980s. Instead of converting sunlight directly into electricity like photovoltaics (PV) do, it relies on the core technology of fossil-fuel generation: steam turbines. The difference is that rather than using coal or natural gas, CSP uses solar radiation as its primary fuel—free and clear of carbon.

Mirrors, the essential component of any CSP plant, are curved or angled in specific ways to concentrate incoming solar rays to heat a fluid, produce steam, and turn turbines. Because CSP relies on immense amounts of direct sunshine, it is best suited to hot, dry regions where skies are clear.

A critical advantage of CSP is energy storage. Unlike PV panels and wind turbines, CSP makes heat before it makes electricity, and heat is easier to store. When equipped with molten salt tanks for heat storage, CSP plants can continue to produce electricity well after the sun goes down.

As of 2014, CSP was limited to just 4 gigawatts worldwide. As the technology becomes more effective and less expensive, the central benefit of reliability will hasten its growth.

* excerpted from the book, Drawdown

Concentrated solar power comprised 0.05 percent of world electricity generation in 2018. Despite slow adoption in recent years, this analysis assumes that this solution could rise to 5.9–7.3 percent of world electricity generation by 2050, avoiding 18.6–24.0 gigatons of greenhouse gas emissions associated with cumulative implementation costs of US$1.7–2.1 trillion. An additional benefit of concentrated solar power is that it can integrate energy storage, allowing for extended use after dark or to be used in peak demand periods.