Thorium Reactors: A Stepping Stone to Fusion

There is a technology that lets us create syngas and electricity at the same time to power our economy.  The waste products of the technology cannot be efficiently weaponized.  It is remarkably abundant and cheap, having the potential to solve energy problems in third world countries.  Reprocessing occurs continuously as a result of the process, leaving behind almost zero waste.  Not just that, but it is inherently safe in design with no chance of dangerous situations like meltdowns.  It sounds like something out of science fiction really, but the thorium reactor is actually a technology from the 1960's that is easily realizable today.

Diagram of the Thorium MSR at ORNL

There was research throughout the 1960's on this particular type of molten-salt reactor design.  In 1964, the US built the first thorium breeder reactor at Oak Ridge National Laboratory.  The reactor operated for the equivalent of about a year and a half of production use.

Thorium prevents proliferation, since the materials used are difficult to weaponize.  The US discovered this early on since it was decided against thorium for that exact reason.  In the US's case, a weaponizable fuel cycle was desired due to the military situation of the times.

For scale, by converting all existing US nuclear reactors to use thorium fuel, our electricity demand would be resolved for at least the next few hundred years.  The countries that have the fastest growing electrical demand, India and China, are going straight to thorium for the aforementioned reasons.  Thorium is about four times as common as uranium in the earth's crust.  Unlike water based reactors, there is no need for a natural source of water such as a river or lake in the vicinity for cooling purposes.  This makes them usable in deserts or even in extraterrestrial operations such as on the moon, where there is a sizable amount of thorium.  If that wasn't enough, thorium even has a unique electrical signature that lets us locate deposits very easily.

Kirk Sorenson Discussing Thorium at TED

The way the thorium reactor works is by sitting in a molten salt.  There is really no concern for melting down, since the core is essentially molten during operation.  In the event of a runaway, the contents of the reactor core, there is a melt-away safety which dumps the contents of the core into a dump tank and shuts down the reactor.

There is an excellent TED talk on the subject for more information.  In it Kirk Sorenson discusses how it can power us until the next energy source comes along.  Looks like this one will give us enough time to get fusion working.