In Which I Use Scientific Reasoning to Doubt the Thorium-Powered Car

Originally published at Live Granades. Please leave any comments there.

While I was away at Dragon*Con, stories about a possible thorium-powered car popped up in the news. From the write-up at Txchnologist:

Charles Stevens, an inventor and entrepreneur, recently revealed that his Massachusetts-based R&D firm, Laser Power Systems (LPS), is working on a turbine/electric generator system that is powered by “an accelerator-driven thorium-based laser.” The thorium laser does not produce a beam of coherent light like conventional lasers, but instead merely heats up and gives off energy.

There’s a whole lot of science word salad in that paragraph — what does it even mean to have a laser that isn’t actually lasing and producing coherent light? So let’s detangle it and see if the proposed thorium-powered car makes sense.

The first thing to know is that there’s been a lot of work done on using thorium for fuel in a nuclear reactor. Thorium-232, the kind you dig up out of the ground, is only weakly radioactive and won’t undergo fission by itself. What you can do, however, is bombard it with slow neutrons from uranium or plutonium. That turns thorium into uranium-233, which is fissile and can be used in a nuclear power plant. That means you can use thorium as breeder fuel to produce the fissionable material you really want.

Thorium has several benefits over uranium-235, the usual nuclear reactor fuel. For one, thorium ore is about three or four times as prevalent in the Earth’s crust as uranium ore. For another, you can use all of the thorium you mine. Only 0.7% of uranium is 235U. The rest of it is 238U, which isn’t useful for nuclear reactors. That makes thorium far more abundant for nuclear power purposes.

There are downsides, of course. As the World Nuclear Associate fact page dryly puts it, “Despite the thorium fuel cycle having a number of attractive features, development has always run into difficulties.” There aren’t any commercial thorium reactors yet.

However, if you read carefully what Charles Stevens is saying, he’s not claiming to be using thorium in a nuclear reactor. The WardsAuto article on Stevens states, “Stevens agrees, emphasizing his system is ‘sub-critical,’ which means no self-sustaining nuclear reaction within the thorium creating significant amounts of radioactivity.” So what is he doing?

Unfortunately his two websites currently have very little information. To find out more we have to look at the 2009 version of his webpage and exerpts from that same page. Back then he talked about laser-driven cars in which a “Hybrid Solid state Free Electron laser” heats up thorium, which releases even more heat to turn water into steam and drive a turbine. Also an accelerator may be involved. And according to what he told WardsAuto, “1 gm of thorium equals the energy of 7,500 gallons (28,391 L) of gasoline Stevens says. So, using just 8 gm of thorium in a car should mean it would never need refueling.”

Right, let’s try and make sense of this, starting with one gram of thorium equaling the energy of 7,500 gallons of gas. This a question of energy density: how much energy can you extract from a given amount of fuel?

I have no clue what process Stevens is claiming to use that lets you bombard thorium with a laser and get energy out, especially since he said it’s sub-critical and thus not a nuclear fission reaction. Instead I’ll pretend he is doing nuclear fission, since that’s one of the more energy-productive reactions we can do and will set a good estimated upper bound on how much energy Stevens could extract from thorium. I’ll also assume 235U fission, since we don’t have a thorium reactor yet.

Uranium in a reactor produces about 20 terajoules of energy per kilogram. For comparison, gasoline gives you about 48 megajoules per kilogram. That means uranium gives us about 425,000 more power per kilogram than gas. Let’s assume thorium will give us roughly the same ratio. That means one gram of thorium would be like 425 kg of gas. Gas has a density of about 2.7 kg per US gallon, so that 425 kg of gas is equivalent to 156 gallons.

That’s way short of Stevens’s claim of 1 gm of thorium being equivalent to 7,500 gallons of gas. For that to be true, his laser-induced power output has to be fifty times more energy efficient than nuclear fission. That is an extraordinary claim, to put it mildly, and he’s offered no proof and precious few details.

Looking through his other claims, it sounds as if he glued together actual science together as if making a collage for kindergarten, regardless of whether the results made sense or not. You could in theory make an actual thorium laser, though that’s not what he’s doing. You can use a particle accelerator to drive a nuclear reaction by knocking neutrons out of other particles, though again that’s not what Stevens is doing despite him adding “accelerator-driven” to the description of his process. You can even induce nuclear reactions using super-powerful lasers, but Stevens says he’s not inducing fission.

So to sum up: Stevens isn’t claiming to have made a nuclear-powered car. He’s claiming to have made a steam-powered car where the steam is heated up when he shines a laser on thorium. I don’t know of any physical process that would let you get more heat energy out of the thorium than you’d spend on making the laser go. For his process to be so awesome that it would power a car for some 200,000 miles on a single gram of thorium, he’d have had to come up with something that’s fifty times more powerful than a nuclear reactor. And he hasn’t released any papers, only press releases. That’s 3 out of 3 red flags for the research not being real.

Sorry, world. If we’re going to have a laser-powered car, it sounds like this isn’t it.


Talking Science at Dragon*Con 2011

Originally published at Live Granades. Please leave any comments there.

It took me a while to realize how much science content there was at Dragon*Con, mainly because I was distracted by Steampunk Zombie Marvel Superheroes Made of Cardboard and Patrick Stewart. Now that I give talks for and hang out around the “reality tracks” in the Hilton (i.e. Space, Science, EFF, Robotics, and Skeptics), I know there’s a tremendous amount of science stuff at the convention. For instance, this year alone we had a solar telescope and a working fusion reactor. We also electrocuted a pickle for science.

All three of my solo talks were well-attended, even my one on D-Wave One and quantum computing that took place on Friday at 11:30 AM. That’s right, for the EFF track’s second panel I talked about qubits and quantum superposition. Thank goodness the audience pretended to be interested! I’ve included my slides and the scripts for my talks. In the scripts, advance the filmstrippresentation every time you see a #. Note that all of my slides use the free font Fontin Sans, and that the online versions aren’t exactly converted properly.

First up, D-Wave One! Learn about quantum computers, qubits, and how many different images I have for “dooooomed”.

(Grab the script | Download the presentation)

Next is Planet Hunting, describing our successful search for planets outside our solar system. I believe this is the world’s first science presentation to combine astrophysics and My Little Pony: Friendship is Magic. (Note: ponies are used strictly for pedagogical purposes.)

(Grab the script | Download the presentation)

Finally there was my robot helicopter talk. This was my busman’s holiday, as a lot of what I talked about is directly relevant to my day job.

(Grab the script | Download the presentation)

Finally I once again took part in the Evil Geniuses for a Better Tomorrow panel, which packed the Hilton Crystal Ballroom. This was something of a science variety show. I got to talk about the leukemia trial that involved patching a patient’s t-cells to replicate like mad and attack the leukeima, said patching being done via a modified HIV variant, and if that doesn’t sound like mad science, I don’t know what is. Jason Schneiderman talked about using magnets to turn off people’s ability to make moral judgements and showed videos of MRI machines sucking in wrenches and office chairs and guns. Paul Gregori electrocuted a pickle to show electroluminescence and then made people in the audience eat the pickle. Chad Ramey showed off his working fusion reactor. And special guest Phil Plait was escorted to the stage by stormtroopers, where he got to talk about death from above and accept an award for Mad Scientist of the Year.

I had a great time with all of those panels, and I hope that attendees both enjoyed them and learned a bit of science at them.


Podcasting at Dragon*Con 2011

Originally published at Live Granades. Please leave any comments there.

My Dragon*Con this year was far more packed than normal, so I’m splitting my normal recap post into several, divided by topic. First up is podcasting! We did our usual live episode of WhatTheCast, which was raucous and fun. We had Patrick Jarrett calling in as our roving sports reporter from Philadelphia, where he was covering the Magic: The Gathering Pro Tour as part of his job as Editor in Chief of Gathering Magic. We got to meet Lizzie Lynch, who learned about Dragon*Con from WhatTheCast years ago and was attending the con for the first time.

Oh, yeah, and we won one of these:

That’s a Parsec Award for Best Speculative Fiction Fan or News Podcast. It’s a juried award, and I was thrilled that we won it.

That would have been plenty to make this Dragon*Con special, but Sunday night topped it all in terms of sheer surreal wonderfulness. Colin Ferguson, who plays Sheriff Carter on the sadly-cancelled Eureka, agreed to be part of Disasterpiece Theatre, my other podcast.

So of course we had to cast him in the Eureka movie as directed by Michael Bay.

Colin Ferguson with Alex White, Brooke Fox and Stephen Granade

He was an excellent guest, funny as hell, and was quite willing to invent terrible things for his fellow Eureka cast members to do in the movie, like having Felicia Day play a villain with an over-the-top German accent.

I will note that the above is not the first picture we took with him. When we asked him if he’d be willing to take a cast photo with us, he said, “Sure! We should do it in the bathtub. We can all pretend to be passed out.”

Colin Ferguson with the cast of Disasterpiece Theatre

I believe this will now be the picture I use for my professional science gigs.


My Dragon*Con 2011 Schedule

Originally published at Live Granades. Please leave any comments there.

I’m a guest at Dragon*Con again this year, which means I’ll be on all kinds of panels. If you’re wanting to find me to say hi or to hang out, your best bet is to find me right after one of these panels. Or you could haunt the Hilton — that’s where all of my panels are save the Late Show.

The Dragon*Con Late Show. Every morning at 9 I and my co-hosts Brian and Ally will go through the latest news, schedule changes, and what’s hot for the day. This gets broadcast on the host hotel channels, so you don’t even have to leave bed!

D-Wave One: The First Commercial Quantum Computer. Friday, 11:30 AM, Hilton 201.
The first quantum computer is now available on the market. Who is buying them and why? Are they ready for prime time? Can encryption be broken?

Answer key: Lockheed Martin, to play with it and see what it can do, sort of, not yet. I expect this one is going to be all kinds of fun, and should be accessible to anyone who’s willing to learn a little bit of binary.

Planet Hunting: Watching Stars Wobble & Dim. Friday, 8:30 PM, Hilton 203.
The new ‘in’ field of astronomy is the search for exo-planets but we don’t have the technology to ‘see’ an exo-planet. So how are we finding so many?

The description is actually inaccurate: we now can see extrasolar planets! And I have to admit, it’s extremely cool that we can. I’ll run through the history of exoplanets including some of the embarrassing claims that turned out not to be planets.

Evil Geniuses for a Better Tomorrow: 9th Annual Recrument Drive. Saturday, 1:00 PM, Hilton Crystal Ballroom.
Methods of taking over the world for fun and profit – demos and audience participation. Plus evil ice-cream and a working nuclear reactor!

We’re not kidding about either the ice cream or the nuclear reactor. My co-panelists and I will go through real mad science, the crazy stuff we’ve been doing, and how to survive as an evil minion.

What The Cast – Live! Sunday, 2:30 PM, Hilton 204.
Join Brian, Crispy, Patrick and Stephen (the team behind DragonConTV) for nerd punditry at its best.

Or at least funny nerd punditry. Last year we had a guy in a squid hat, the team behind Chad Vader, and our one Zune listener. Who knows what we’ll have this year? (Seriously: we don’t even know. That’s improv for you!)

Helicopter Drone Units. Sunday, 5:30 PM, Hilton 208/209.
Autonomous helicopter drone talk and tentative demonstration.

Sadly no demonstration, as the quadcopter demo isn’t ready for prime time yet, but I will go through the awesomeness that is robot helicopters and how they’re taking over the world.

RevolutionSF’s RevCast – Live! Monday, 1:00 PM, Hilton 204.
Join the crew from RevolutionSF for a live recording.

Well, the crew from RevolutionSF and me. I’ve guested on several RevCasts and had a blast, so I’m looking forward to doing it live with the crew.

So come say hi! Stop by one of my panels and ask pointed questions! It’ll be fun.


First Day of Second Grade

Originally published at Live Granades. Please leave any comments there.

And Liza starts preschool tomorrow.

We stepped outside this morning to take this photo and there was a cool breeze blowing. Nice change of pace to the hot weather we’ve been subjected to most of the summer. The summer is over and I’m glad to see it go. I’d like very much now to settle into a boring routine for at least six months.


It’s a Disasterpiece!

Originally published at Live Granades. Please leave any comments there.

I’m pleased to announce Disasterpiece Theatre, a new podcast in which I and my co-host Alex White come up with the worst idea for a movie that we think Hollywood might actually make. We pick a topic, like animal horror, or an actor, like Milla Jovovich, and each come up with a movie that we pitch to the other. Then, in grand Hollywood tradition, we tell each other how wonderful the idea is, but that it still needs a bit of tweaking…. By the end we’ve got some awesomely terrible movie ideas.

Don’t believe me? How about a Betty White and Tracy Morgan buddy dramedy where Tracy raps? Or a period family drama starring Milla Jovovich, Brian Dennehey and Albert Finney in which Milla Jovovich is in the Vietnam war?

By the way, those are some of our less-bad ideas so far.

So head to the website and listen to me and Alex describe our bad movies while our long-suffering producer Brooke Fox tries to rein us in. You can also subscribe through iTunes. We’re also on Twitter, should you wish to tell us your terrible movie idea.


We’re Up For Two 2011 Parsec Awards!

Originally published at Live Granades. Please leave any comments there.

Two of the podcasts I’m involved with are finalists for the 2011 Parsec Awards, which celebrate excellence in speculative fiction-related podcasts. WhatTheCast is up for Best Speculative Fiction Fan or News Podcast (General), and Dragon*Con TV is in the running for the Best Speculative Fiction Comedy/Parody Podcast. I’m excited that both are finalists, especially given the competition in those categories. Come Dragon*Con 2011, we’ll see if we win!


These Are Relevant to My Interests

Originally published at Live Granades. Please leave any comments there.

Misty and I have been crazy busy thanks to life and work and kids and everything, so in lieu of actual content, have two videos!

First, what if Harry Potter and the Half-Blood Prince were really a teen coming-of-age comedy?

Second, what if Pinkie Pie from My Little Pony: Friendship is Magic were possessed by the Space Core from Portal 2?

The answer to both questions, of course, is “It would be awesome.”


Continuing the Franchise

Originally published at Live Granades. Please leave any comments there.

Now that the Harry Potter movies are over, I expect that there are movie executives scrambling around, trying to discover the next big thing. Since young adult books are still popular, I expect that’ll be their focus — perhaps the Hunger Games trilogy or Cassandra Clare’s The Mortal Instruments series will garner a huge audience.

I have a humble suggestion: why not re-work the Harry Potter series? After all, with a few tweaks I think you could bring in a whole new audience. To that end, I give you a scene from



The room in this broken-down shack is dominated by KEMPTID, a giant of a man with an umbrella. He is talking with RICHIE, a young eleven-year-old with round glasses and dark hair.

     Y’see, Richie, yer’ a wizard.

     I’m a what?

     A wizard, o’ course, and a thumpin’ good’un, I’d say, once yeh’ve trained up a bit.

     That makes no logical sense.

     What d’yeh mean?

     Look, there isn’t any such thing as magic. The universe can be perfectly explained by the natural laws of science.

          (taken aback)
     But, but yer parents–

     They died in a car crash.

     No. He Who Must Not be Named, a dark wizard, killed ‘em!

     Really? That’s more plausible than a car crash? There are a little over two thousand car-related deaths per annum in the UK. Do the math.

     But…but…all th’ letters, Richie! And I c’n do magic with my umbrella!

     Any stage magician worth his salt could do the same. Your anti-scientific flim-flammery will find no toehold with me, sir. Now shove off. I’ve got a perfectly mundane life as a friendless orphan to live.

I’m not sure how to spin this out into eight movies, though. Perhaps I should have taken the approach that Eliezer Yudkowsky took for Harry Potter and the Methods of Rationality.


Hey, Stephen, How’s Liza Recovering From Her Surgery?

Originally published at Live Granades. Please leave any comments there.

Friday, Liza had minor surgery to close an umbilical hernia. Our scene takes place Sunday afternoon.


This standard suburban living room is square and has all of its furniture away from the walls, leaving a continuous track around the center of the room. The MAN is in the living room. The GIRL enters and begins running laps around the room.

     Hey, what’re you doing?

     Running a race. I’m racing my invisible friend Jai Alai.

The GIRL continues to run at top speed.

     Is that hurting your stomach?

     Yeah. (beat) But I don’t care.

Exeunt omnes