What's the easiest way to deal with the intermittency of many renewable sources of energy? Cheap storage. And what form of storage is much cheaper and has a much higher round-trip efficiency than electric storage? Thermal storage.

That's a key reason concentrated solar-thermal power (CSP) is a core climate solution. It has the most potential of any zero-carbon electricity since it can most easily be integrated with thermal storage -- technology that is available today, as made clear by this just announced 200-MW plant Albiasa Solar of Spain will build in Arizona:

Albiasa officials said they planned to use molten salt to store heat from the plant so it can keep generating power after sunset.

That also is the plan for Solana Generating Station, a 280-megawatt solar-thermal plant planned for Gila Bend by Abengoa Solar Inc. of Spain.

APS announced that it would buy the energy from that power plant once it is running in 2011. Last year, officials said they were struggling to get financing for the project, but APS spokesman Steven Gotfried said Friday the plans were moving forward.

The ability to provide power reliably throughout the day and evening in key locations around the world (including China and India) is why CSP delivers 3 of the 12 - 14 wedges needed for “nuclear needs a place for its waste, which CSP doesn't, and nuclear has obvious production bottlenecks and takes forever to build safely, which CSP doesn't).

Moreover, unlike nuclear, the world hasn't really built many CSP plants until very recently, so costs are projected to drop steadily down the experience curve for new technology in the coming decade thanks to economies of scale and technology learning. As the 2006 report “Economic, Energy, and Environmental Benefits of Concentrating Solar Power in California,” for the National Renewable Energy Laboratory, by Black & Veatch concluded:

A comparison of the levelized cost of energy (LCOE) revealed that the LCOE of $148 per MWh [14.8 c/kwh] for the first CSP plants installed in 2009 is competitive with the simple cycle combustion turbine at an LCOE of $168 per MWh, assuming that the temporary 30 percent Investment Tax Credit is extended.

The ITC was extended 8 years in the bailout bill. And this analysis was really aimed at 2015 costs:

CSP plants installed in 2015 are projected to exhibit a delivered LCOE of $115/MWh, compared with $168/MWh for the simple cycle combustion turbine and $104/MWh for combined cycle plants. At a natural gas price of about $8 per MMBtu, the LCOE of CSP and the combined cycle plants at 40 percent capacity factor are equal.

And that is without a carbon price.

Look out nukes and dirty coal, the future is here!

This piece originally appeared in Climate Progress.