#1 cleantech news, reviews, & analysis site in the world. Subscribe today. The future is now.

Clean Power

Published on May 23rd, 2018 | by Tina Casey


Bitcoin Or Not, Here’s Why Concentrating Solar Power Is The New Nuclear

May 23rd, 2018 by  

Whoa. File this one under D for Don’t look back, bitcoin may be gaining on you. Bitcoin’s voracious energy-sucking habit is coming into sharper focus, and that could throw a big, fat, old-fashioned monkey wrench into the idea that solar power, wind power, and other renewables can be ramped up enough to power the all-electric economy of the future.

That leaves a big, wide opening for conventional “cleaner” fuels like nuclear energy, natural gas, and even coal. Or, does it?

The Case For Nuclear Energy In The Sparkling Green Future

CleanTechnica took note of the environmental problem lurking behind bitcoin back in 2013, and we caught up with bitcoin’s growing power habit last year.  The latest bitcoin study comes from our friends over at Grist, who report that “bitcoin’s energy use got studied, and you libertarian nerds look even worse than usual.”

In other words, we’re gonna need a lot more juice than previously thought.

To add more electricity without tipping the climate change bucket, fossil fuels are generally in a weaker position than nuclear energy, so without digging too deeply into the weeds let’s zero in on the nukes.

Just yesterday, the Department of Energy made the case for nuclear energy in a blog post titled, “It’s Time for the World to Recognize Nuclear as a Clean Energy Source.”

Even without the bitcoin angle, the gist of the Energy Department’s argument is that nuclear energy provides a “clean, reliable, and resilient source of electricity” for other growing needs.

Here’s their short list:

  • Desalination
  • Industrial process heat
  • Integrated nuclear-renewable systems
  • Flexible electricity grids
  • Hydrogen production
  • Energy storage (thermal, electrical, or chemical)

The devil is in the details, though. Nuclear advocates are looking for growth hotspots in regions like the Middle East and China (thanks, Bill Gates!), where local opposition is not a particularly troublesome obstacle for energy developers.

The situation is different in countries like the US, where the ghost of Three Mile Island still lingers over the prospects for renewing the nation’s stock of aging nuclear power plants.

Aside from environmental concerns, the falling cost of renewable resources in the US makes nuclear power look like bad economic policy, to boot.

That doesn’t mean nuclear energy will evaporate completely in the US, but it does mean that the prospects for growth are limited.

Meanwhile, innovative new forms of solar power and other renewables have a good chance of leaping into the breach, .

Solar Power As The New Nuclear

That’s where solar power comes in. More specifically, that’s where concentrating solar makes an entrance.

The US has been a big fan of concentrating solar power despite some earlier criticisms, and the Energy Department is still exploring ways to kick the technology up to the next level.

That brings up some interesting comparisons with the development of nuclear energy.

Recall that the US solar industry got a jumpstart from the space race between Russia and the US, but it took another generation (or more) before the technology found its footing in commercial use on Earth.

That kind of trajectory is similar in the nuclear industry, where the nuclear arms race of World War II pumped up the early stage R&D muscle, then it took a while before the technology transferred to civilian energy production.

Coal was the dominant power source back then, so it was relatively simple to sell nuclear on the basis of high output, high reliability and less air pollution.

The problem for nuclear power nowadays is that solar power and other, cleaner options are available.

The reliability issue is also becoming a moot issue with the advent of energy storage and smart grid technology.

As for high output, the Energy Department just announced a new $72 million round of funding for new high temperature concentrating solar power technology, so let’s take a quick look at one of the teams in that batch.

The Falling Particle Factor

The new round of funding is split among three teams, which are competing to see who gets to build a new facility for testing new high temperature CSP technology.

Sandia National Laboratories will lead one of the teams with a $10.5 million slice of the funding pie, and earlier this week the lab sketched out its goal:

Current concentrating solar power systems can heat a substance to 565 degrees Celsius. The goal of this new project is to reach temperatures greater than 700 C, which would boost efficiency and lower the cost of electricity generated from concentrating solar power.

For those of you new to the topic, CSP involves using specialized mirrors to focus sunlight on a central point. That heats a liquid that can be used to produce steam to generate electricity. The liquid can also double as an energy storage medium, and/or excess electricity can be stored in batteries.

Sandia’s twist is to use ceramic particles as a sand-like medium for trapping solar heat and storing it.

The technology is called “falling particle” because the particles are literally dropped through a beam of concentrated sunlight.

The advantage is that the ceramic particles are more durable than molten salt, which is the conventional material of choice for CSP:

The falling particle receiver developed at Sandia drops sand-like ceramic particles through a beam of concentrated sunlight, and captures and stores the heated particles in an insulated container below. The technique enables operating temperatures of nearly 1,000 degrees Celsius.

Such high temperatures translate into greater availability of energy and cheaper storage costs because at higher temperatures, less heat-transfer material is needed.

According to Sandia, the current crop of CSP systems are only about 40% efficient in terms of converting thermal energy to electricity. Falling particle technology could jump that up to 50% — or far more.

Here’s the outlook from Sandia engineer Cliff Ho, cited in a 2013 Sandia press release:

Our goal is to develop a prototype falling particle receiver to demonstrate the potential for greater than 90 percent thermal efficiency, achieve particle temperatures of at least 700 degrees Celsius, and be cost competitive. The combination of these factors would dramatically improve the system performance and lower the cost of energy storage for large-scale electricity production.

The 2013 leg of the project was initially funded at up to $4 million through former President Obama’s SunShot Initiative, resulting in the successful demonstration of a prototype device.

Ho is still leading the project, and in this week’s press release he explains the next steps:

We have demonstrated a prototype for the continuously circulating falling particles, and now we are adding six hours of storage, a 1-megawatt heat exchanger and a particle lift to demonstrate the entire thermal system.

Ho also explains the advantages of ceramic particles:

We believe particles are the best option for going to higher temperatures for advanced power cycles. The particles are inexpensive, durable and non-corrosive. They can be stored directly, they don’t freeze and they can reach temperatures over 1000 C.

So, onwards and upwards. The Sandia team has two years to hammer out the details, then design a pilot-scale facility and see how it stacks up against the other two teams. The winning team will get another $25 million to construct and operate the facility.

Speaking Of Nukes…

Meanwhile, for those of you familiar with Saudi Arabia’s recent pursuit of nuclear energy, here’s an interesting tidbit: the Sandia CSP team includes King Saud University and the Saudi Electricity Company among its long list of partners.  King Saud University was also a partner in the 2013 round.

And, Saudi Arabia is also a partner in what will be the world’s largest PV power plant, so there’s that (wait — bigger than this one?).

Hmmm, hedging bets, much? If you have any thoughts on where Saudi Arabia is heading with its energy policy, drop us a note in the comment thread.

Come to think of it, lend us your ideas about bitcoin. Are we locked in a losing game of energy whack-a-mole or can bitcoin go mainstream without consigning us to all but certain doom?

We’ve reached out to Sandia to bring you some additional insights into falling particle technology, so stay tuned for more on that.

Follow me on Twitter.

Photo: via Sandia National Laboratories, falling particle receiver for CSP.

Support CleanTechnica’s work via donations on Patreon or PayPal!

Or just go buy a cool t-shirt, cup, baby outfit, bag, or hoodie.


About the Author

specializes in military and corporate sustainability, advanced technology, emerging materials, biofuels, and water and wastewater issues. Tina’s articles are reposted frequently on Reuters, Scientific American, and many other sites. Views expressed are her own. Follow her on Twitter @TinaMCasey and Google+.

Back to Top ↑