Here’s something that should send a chill right down the spine of US natural gas exporters. A new study is out that indicates how a network of utility scale concentrating solar power plants could provide the same grid reliability as conventional power plants in some regions, without costing any more than gas-fired power plants.
The new study, “Potential for Concentrating Solar Power to Provide Baseload and Dispatchable Power,” was conducted under the auspices of the International Institute for Applied Systems Analysis. It has just been published in the journal Nature Climate Change.
Concentrating Solar Power Vs. Solar Cells
For those of you new to the topic, concentrating solar power (CSP) refers to the use of specialty mirrors, called heliostats, to focus sunlight on a central point. A large scale CSP plant typically consists of thousands of ground-mounted heliostats focused around a central tower. The concentrated solar power heats a liquid piped through the tower, which circulates to a boiler where it creates steam to run a turbine.
Another typical configuration consists of long rows of parabolic, trough-shaped mirrors, with pipes running along the middle.
The hot liquid can double as an energy storage system, enabling a CSP to continue generating electricity long after dark. That provoides CSP with an effective dispatchabilty factor, unlike photovoltaic cells which require a separate storage system.
Solar cells have some built-in advantages of their own, including scalability, which is why you probably won’t see much in the way of small-scale CSP on the market.
Utility Scale Concentrating Solar Power
That leads us to utility scale CSP, which here in the US is coming out of the box with a bang, thanks to considerable support from us taxpayers.
Back in May, the US Department of Energy dubbed 2014 the “Year of Concentrating Solar Power” to highlight the launch of five utility-scale CSP plants, including the now-familiar Ivanpah, Solana, and Crescent Dunes projects.
These include some of the largest and most innovative CSP plants of their kind in the world, so let’s all do a group hug with the Energy Department:
These innovative CSP plants illustrate how the Energy Department advances high-impact clean energy technologies from inception to market through sustained, long-term investments.
First, Energy Department research and development programs — like the SunShot Initiative — advance early-stage technologies. In this case, CSP technology was initially developed with the support of the Energy Department’s Office of Energy Efficiency and Renewable Energy.
Then, our Loan Programs Office worked with the private sector to encourage investment and accelerated deployment of CSP technology at commercial scale.
Exporting Concentrating Solar Power Vs. Natural Gas
Yes, everybody knows that solar-generated electricity is not exportable overseas, at least not yet. But technology is certainly exportable, and we’ve previously made the argument that in terms of climate management, it makes far more sense to export renewable energy technology than to continue exporting fossil fuels.
That brings us around to the topic of natural gas exports from the US.
Natural gas has been touted as a “cleaner” fossil fuel than coal, but that comparison has been pitched on rather shaky ground, especially when the local impacts of natural gas drilling are taken into consideration.
Nevertheless, US legislators have been pushing for an increase in natural gas exports, hostilities between Russia and Ukraine being the latest excuse.
The New Concentrating Solar Power Study
No, we didn’t forget about that study. While the authors probably did not set out to blow a giant raspberry at the US natural gas lobby, the findings do indicate that at least some energy-hungry nations can modernize their electricity supply through CSP, without relying on natural gas.
The key, according to the study, is that CSP planning needs to be done on a national or regional level to establish a coordinated network, rather than constructing a series of one-off projects.
The study is apparently the first of its kind to take into account optimal network planning factors for renewable energy, including the specific use of CSP, along with demand-side management and grid-scale energy storage.
Here’s the money quote from the study abstract:
We simulate the operation of CSP plant networks incorporating thermal storage in four world regions where CSP is already being deployed, and optimize their siting, operation and sizing to satisfy a set of realistic demand scenarios. In all four regions, we show that with an optimally designed and operated system, it is possible to guarantee up to half of peak capacity before CSP plant costs substantially increase.
The four regions included in the study perform in different ways. One clear winner is the Mediterranean region:
In the Mediterranean region, for example, the study shows that a connected CSP system could provide 70-80% of current electricity demand, at no extra cost compared to gas-fired power plants. That percentage is similar to what a standard energy production plant, such as a nuclear plant, can provide.
The US natural gas export lobby has the upper hand for now, but as the saying goes, don’t look back. Something might be gaining on you.