Hands up: Who thinks nuclear power is safe?
Before the Japan earthquake and tsunami on March 11, opinion surveys showed that most people thought it was.
But as radiation seeps from the stricken Fukushima power plant, the world suddenly seems a very different place.
Fossil fuels have nearly run out, and we all want safe, clean and affordable power for this generation and the next. But is this an impossible dream?
Today's post describes how it is possible: It can be done with a hitherto little-known type of nuclear power - yes, you read that correctly - called the thorium reactor.
A thorium reactor is completely different from the Fukushima power plant design. A thorium reactor doesn't produce radioactive waste that lasts a thousand years, it won't ever have a Chernobyl-like "meltdown," and it can't be used to make an atomic bomb.
And here's the sucker punch: We've known about this super-efficient green technology for more than 50 years.
Thorium technology was mothballed in the 1970s for financial and political reasons - this could well be a real-life conspiracy. Had Fukushima been a thorium reactor, things would have been very different.
The great conspiracy
Why haven't you heard of thorium reactors before?
A brief history of nuclear power: Back in the 1950s, atomic energy had just been born. Researchers and engineers slavishly tested dozens of different ways to yield this newfound source of power: There were literally thousands of ways to split an atom. But one method won out: the solid-fuel uranium reactor.
A decision made in the early 1950s set in motion the wheels that mean nearly every nuclear power plant today is based on this technology. The thing is, the solid-fuel uranium reactor wasn't the best design. Not by a long shot.
Why pick a bad design? In the early 1950s, the U.S. military wanted nuclear bombs. The fastest way to get them was by getting uranium reactors built. That way, the military would have an abundance of the raw material it wanted for bomb-making - Plutonium-239, a nasty waste-product of a normal uranium reactor.
It really didn't matter that uranium reactors were pretty inefficient, tended to overheat and relied on a rock that needed intensive mining and refining. They had a bigger agenda.
It was known then, and nuclear physicists know it now: There is a much better, safer and more environmentally friendly way to split an atom - the liquid-fuel thorium reactor.
It's safe: Nuclear reactors, like the one at Fukushima, need constant cooling - even if they've been switched off. Nuclear "meltdown" happens when these cooling systems fail (like in Fukushima) and the uranium fuel core overheats. But within a thorium reactor, a meltdown simply isn't possible - turn the power supply off and the reaction just stops.
It's cheap: At the moment, thorium is being thrown away. In rare-earth metal mines around the world, millions of tons of thorium are extracted. They don't need it - and so these companies are literally paying someone to get rid of it.
It's efficient: Thorium reactors (also called LFTRs) use liquid fuel rather than solid uranium. Liquid fuel means things can mix together better, meaning thorium reactors are 200 to 300 times more efficient than even the best uranium reactor. Powering a million homes for one year needs only one ton of thorium, compared to 250 tons of uranium.
It's clean: Thorium burns much more cleanly than uranium and produces only 1 percent of the waste. Much of the waste from a thorium reactor is actually quite useful and can be reused for powering space probes (among other things).
Reactors are easy to build: Conventional nuclear power plants take about 15 years to set up and build. A thorium reactor is a much more simple structure and operates at a much lower temperature; therefore, it can be much smaller and faster to build.
Is nuclear the future?
Staring in the face of fossil fuel shortages and impending climate change, the world desperately needs to change. Before now, I have never liked the idea of nuclear power being a part of that future - radioactive waste and nuclear disasters just don't really appeal. But thorium reactor technology seems to offer a great compromise for safer, greener energy.
Thanks to the Internet, the word about alternative nuclear power is slowly getting out. Online communities such as EnergyFromThorium are also gathering momentum in the Western world.
But politicians and energy companies are reluctant to invest in change. At the moment, the only country that is really taking thorium technology seriously is China - and the Chinese are leading the way in researching and developing new-generation thorium power stations.
Had Fukushima, Chernobyl and Three Mile Island had thorium reactors, today's newspapers would be telling a different story. My hope is that the ongoing tragedy in Japan can act as a catalyst for change.