Hi Salting The Earth: New Molten Salt Reactor Looks For Commercial Success.

Hi Salting The Earth: New Molten Salt Reactor Looks For Commercial Success.

Nuclear power has always been a delicate subject, and recent contamination issues such as those in Fukushima have put “traditional” nuclear power under the microscope again.

Thankfully, there’s an alternative: salt. Not the shaker kind or the sea variety, but molten uranium or thorium suspended in liquid and used to generate anywhere from 29 to 290 megawatts of electricity.

This isn’t a new technology, but new iterations have real potential in an evolving power market. The question is: What can this seasoned nuclear option bring to the table?

From Water to Salt:

In the late 1940s, American Naval researchers started looking for ways to put nuclear power plants into air craft carriers and submarines. The answer? Pressurized water reactors that used high pressure – on the order of 160 atmospheres – to keep hot water in liquid form even at 330 degrees Celsius.

The benefit? Lots of hot steam for electricity and propulsion. Downsides? The reactor was heavy, hard to maintain, and if something went wrong, radioactive components came blasting out with 160 atmospheres of force. In submarine jargon, that equates to “we’re all going to die.”

The Oak Ridge National Laboratory meanwhile, went looking for a lighter, less strip-the-flesh-from-your-bones way of getting nuclear reactors into airplanes – and they came up with the molten salt reactor (MSR).

Here’s how it works: Molten salts of uranium or thorium are mixed with water and undergo a continuous nuclear reaction, but without high pressure. If breached, there’s no sudden explosion and no risk of meltdown since the fuel medium is already liquid.

In addition, MSRs produce far less waste material than water-powered plants when decommissioned, and over 80 percent of MSR waste is short-lived. Despite their benefits, salt-based options lost out to other technologies in the early 1970s.

The Great White North:

Just as fashion trends re-emerge after a few decades of dormancy, so it is with nuclear power generation.

Power company Terrestrial Energy has plans to build prototype, low-enriched uranium MSR reactors in Canada over the next few years. The company is tweaking standard design by eliminating graphite as a high-temperature moderator and instead using a sealed reactor space with room for two modules: one in use and one cooling off.

Each unit will last seven years and used reactors will provide recyclable materials. Canadian performance-based licensing means the company should be able to achieve government approval in just a few years and then transition to U.S. applications.

Stay Salty:

The bottom line: In combination with solar, wind and natural gas power sources, MSRs makes more sense than highly pressurized and radioactive water.

Sure, consistent power plant maintenance is crucial to avoid the spectre of nuclear contamination but using a more familiar medium like salt cuts down on public superstition – no need to toss this one over your shoulder.