Dad’s Introduction to Thorium

Dad walked in the door exhausted but satisfied after another hard ten-hour day of accounting work at the office. But this particular day had been unusual. He was proud and deeply honored to have helped a Gold Star mom settle the estate of her recently killed-in-action son at no charge. Money isn’t everything.

“Hi everybody! What’s for dinner?”

Smiling, his eighth-grade daughter, Nancy, looked up from her homework assignment.

“Hey, Dad! Mom’s making spaghetti tonight. Judging by that great smell, I think it’s almost ready.”

“Sounds great! After today, I can use some real comfort food. And how was your day at school? Still bummed about that last math test?”

“Nah, I just need to get tuned in to logarithms. At least I passed. By the way, my science teacher, Mr. Morrisey, started a new subject this week. It looks pretty exciting. Have you ever heard of an element called thorium?”

“What-i-um? No, can’t say I have. Okay. I’ll bite. What is it?”

“Thorium. It’s a natural element about three times more common than uranium that can be used to make electricity.”

“Something new?”

“Actually, Mr. Morrisey said it’s really pretty old.  They tested it out back in the 1950s and ’60s, built a special atomic reactor designed just to use it, and ran it for over four years. It worked great!”

“If it was so great, why aren’t they using it now? They probably found some problem with it that would generate a black hole and kill everybody. I’m sure this what-i-um stuff costs a huge fortune making it uneconomical. You know I do accounting for a living. Cost is always the deciding factor.”

“Mr. Morrisey told us the reason they stopped was because thorium generally can’t be used to make nuclear weapons and bombs. And in the fifties and sixties, that was the goal of almost all the government atomic programs. The electricity making side of the uranium and plutonium was sort of an afterthought to sell the nuclear idea to the public as the peaceful atom.”

“Yeah, the peaceful atom . . . Three Mile Island! Chernobyl! Fukushima! Real peaceful. Now we have radioactive salmon swimming up the Columbia River!”

“Mr. Morrisey talked about that, too! It’s because the old uranium power plants like Fukushima have to use high-pressure water to keep them under control, and that makes them a ticking time bomb when an accident happens. The uranium core melts, all that pressure gets released, and the radioactivity inside gets blown all over the countryside and contaminates everything for centuries!”

“He also told us that the old thorium designs didn’t need either the water or the pressure to keep things under control. To make it work, they mixed the thorium into a really hot melted salt. The thorium got slowly converted as it was needed to a safer non-bomb kind of uranium, which then split by nuclear fission in the reactor that released energy. He said it’s like driving a car but opposite. With uranium reactors, the controllers have to keep their foot on the brake or it runs away. With thorium, its like normal driving. The controllers have to keep their foot on the gas to keep it running.”

“Okay. What if someone accidentally floored the gas pedal and the thing started to run away?”

“Well, it so happens that someone asked that question and Mr. Morrisey said the extra heat made the salt swell up inside, and the swelling diluted the reaction, which automatically slowed it down again, and still it didn’t increase the pressure. So they were sure it couldn’t blow up!”

Mom called out from the kitchen. “Dinner’s ready! Nancy! Go drag your brother off that iPad and tell him to come eat with the family!”

As they sat down to Mom’s delicious spaghetti dinner, Dad began to become more intrigued with his daughter’s obvious interest in this new what-i-um stuff. He wanted now more than ever to test her depth of interest and try to catch his know-it-all kid with a “gotcha!” question she couldn’t answer.

Dad said, “Okay Miss Smarty-pants, what about Fukushima? They say the reason it blew up was the loss of their electric generators that stopped all their water pumps and made the thing overheat. What happens with the what-i-um thing when the power quits?”

“Mr. Morrisey talked about that, too. That’s one of the neat things about the thorium system. When they turned the power off to test their experimental reactor’s ability to deal with an accidental power outage, the electric cooling fan that kept a drain pipe full of frozen salt cool also quit. The salt in the drain pipe warmed up and melted. The whole reactor full of molten salt with reacting thorium, uranium, and everything else in there drains by simple gravity down the now-open pipe into a special underground tank where it all began to cool. He said the tank was shaped and made so that the nuclear reactions stopped but the salt stayed melted for a long time from what he called decay heat. There was still no pressure to blow it up! And when they fixed their practice electrical problem, they pumped the melted fuel salt back into the reactor, and restarted the whole thing because the reactor doesn’t get damaged at all!”

“Dad.” Nancy continued with a wry smile. “There is something else with this thorium reactor business that you will especially like.”

“Okay. I’ll bite again. What am I going to like?”

“There are thousands of tons of thorium already mined and just sitting around. It’s considered a waste by the rare earth mineral miners, and they will actually pay someone big bucks to cart it off their hands. But that’s not the coolest thing. When the thorium systems get going, they can put almost all the coal, oil, and natural gas companies out of business because the thorium is safer, has tons less radioactive waste, and is a lot cheaper to operate than the others. Which means, Dad, that this new-old garbage material will be worth trillions of dollars. That’s trillions with a t. Not to mention that there is no carbon dioxide or methane to mess up the climate or long-lived radioactive waste to be stored hundreds of thousands of years. But I asked him, ‘Wouldn’t a lot of people lose their jobs?’ Mr. Morrisey said the new power would change the way we use all the fossil carbon and end up creating more and better jobs! I like Mr. Morrisey.”

She sensed she might have finally gotten through to Dad in a language he best understood from the heart—compassion. She had the best dad, who also happened to be an expert in understanding how money makes the world go round.

Nancy continued. “Dad, if you’d like to find out more about the thorium reactors and what the possibilities are, I can pull you up a couple of websites with good explanations. Or better yet, the school parent-teacher meeting is scheduled for next week. You’ll love Mr. Morrisey! He has a real cool way of explaining the most complex science things. I’m sure he’d love to meet you and . . .” Nancy said with a huge wink. “. . . tell you and Mom what a great kid you have!”

“Yes. I’ll have to check into this a little closer. Maybe there might just be something to all this. I still don’t understand it all. But it sounds like there might be money to be made from this process as well as improving the environment and creating jobs. Maybe Mr. Morrisey can add something that a non-scientist money-guy can understand. Can you pass the spaghetti, please?”

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