We’ve been on a concentrating solar power/thermal energy storage tear this week, so let’s keep the ball rolling. The Australian science agency CSIRO is working on a super duper “supercritical” steam system for concentrating solar power plants, and in a lucky twist for us over here in the US it turns out that one of CSIRO’s partners in the project is Abengoa Solar.
We stand to gain because the partnership will complement Abengoa’s considerable experience in the field, and the company has just teamed up with our own Energy Department on an advanced new concentrating solar power/thermal energy storage system. The project is aimed specifically at bringing thermal energy storage technology into the competitive energy market.
More Concentrating Solar Power With Thermal Energy Storage!
The Energy Department’s advanced CSP/TES project comes under the National Renewable Energy Laboratory. The role of Abengoa Solar will be to manage the systems integration end of things and perform technical-financial analysis, all with the aim of keeping the cost of the technology down.
The cost factor is critical because CSP is typically more expensive than photovoltaic cell technology, leading some solar cell fans to look down upon CSP.
However, the “built-in” thermal energy storage feature of CSP is a key advantage (see yesterday’s post for a brief overview of CSP/TES). It enables CSP plants to keep generating clean electricity long after the sun goes down.
There’s also a ripple effect on other forms of clean energy tech, namely solar cells and wind turbines. By introducing more time-shifting capability, CSP/TES can create more space on the grid for technology that only functions when the sun shines or when the wind blows.
Abengoa is best known for its trough-style concentrating solar power technology, as illustrated by the company’s new Solana CSP plant with a molten salt thermal energy storage feature. Located in Arizona, Solana is billed as the largest parabolic trough CSP plant in the world.
Abengoa is also a global developer of tower-style CSP plants. Last year the company teamed with BrightSource on the Palen concentrating solar power project in California, which last time we checked will sport the world’s largest CSP towers (for the record, BrightSource is also behind the Ivanpah CSP in California).
Super-Duper Supercritical Steam For Concentrating Solar Power
Now, here’s where it gets interesting. Australia’s CSIRO (short for Commonwealth Scientific and Industrial Research Organisation) teamed up with Abengoa and the Australian Renewable Energy Agency to create a CSP breakthrough that consists of a solar powered system for generating super hot, pressurized “supercritical” steam.
The project apparently resulted in the highest temperatures ever achieved globally for steam generated by non-fossil sources.
Currently, solar thermal power plants in commercial operation use subcritical steam, which is hot enough but performs at a lower pressure. Boost the pressure and you boost efficiency, leading to lower costs.
The supercritical steam achievements means that solar energy could have the same rate of performance as coal or gas in power plants. When you combine that with thermal energy storage capability or with other advanced battery technology, the need for building new fossil fuel power plants pretty much evaporates.
Here’s CSIRO Energy Director Dr. Alex Wonhas waxing enthusiastically about the project:
It’s like breaking the sound barrier; this step change proves solar has the potential to compete with the peak performance capabilities of fossil fuel sources.
Instead of relying on burning fossil fuels to produce supercritical steam, this breakthrough demonstrates that the power plants of the future could instead be using the free, zero emission energy of the sun to achieve the same result.
In Australia, supercritical steam is a new thing even for fossil fuel power plants. According to CSIRO, 90 percent of the electricity in Australia is generated by fossil fuel, but only a few of those power plants use supercritical steam.
According to the CSIRO blog, the R&D team achieved a temperature of about 570° Celsius, which is hot enough to start melting an aluminum alloy. The pressure reached 23 megapascals, equivalent to a two-kilometer diver under the ocean’s surface.
The secret sauce for the achievement is a fully automated control system for fine-tuning the tracking movements of the heliostats (mirrors). That enables the system to focus the maximum amount of solar energy on the receiver without overheating it.
Oh, The Irony
The team cautions that additional R&D is needed to bring the technology to the marketplace, but in the meantime our friends over at Think Progress have tipped us that Australian Prime Minister Tony Abbott is touring around the US.
Maybe he’s on his way over to the National Renewable Energy Laboratory to see what CSIRO partner Abengoa is up to, but according to Think Progress his first stop was in Canada to meet with Canadian Prime Minister Stephen Harper, apparently to keep the global market for fossil fuels humming right along:
…Abbott “flagged intentions to build a new center-right alliance led by Canada, Britain and Australia along with India and New Zealand,” in an effort to “dismantle global moves to introduce carbon pricing, and undermine a push by U.S. President Barack Obama to push the case for action through forums such as the G20.
If Abbott is successful, that would pretty much cut the legs out from under CSIRO’s project in the competitive global energy marketplace, supercritical steam or no supercritical steam. He’s scheduled to meet with President Obama later this week so stay tuned.
Don't want to miss a cleantech story? Sign up for daily news updates from CleanTechnica on email. Or follow us on Google News!
Have a tip for CleanTechnica, want to advertise, or want to suggest a guest for our CleanTech Talk podcast? Contact us here.