How Garbage-powered Cars Could Work

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We're not so far off from being able to power our cars using beer and banana peels, like Doc in Back to the Future. Rather than solving the energy crisis with Mr. Fusion, though, we'll be taking advantage of a technique that's been in use for hundreds of years: creating syngas through pyrolysis.

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Female Announcer: Welcome to Stuff You Should Know from

Chuck Bryant: Hey buddy.

Josh Clark: Yeah.

Chuck Bryant: Before we get started we have a big announcement here about a time change on our TV show.

Josh Clark: Yeah. Again, we have a TV show. It's pretty awesome. We are now on Saturdays, beginning at noon. They're playing it in blocks. So you can just sit down and basically totally lose yourself in the SYSK TV world.

Chuck Bryant: Yeah, I think people like marathon TV shows these days. I know I do.

Josh Clark: Well, yeah. Nick at Nite originated as that kind of thing.

Chuck Bryant: Oh, did they really?

Josh Clark: The world has been eternally grateful ever since. For me, those were the first marathons I ran into.


Chuck Bryant: I call it mainlining. That's what we do at our house. We'll get a new show and we'll watch three seasons over two weeks until we just can't stand it anymore.

Josh Clark: So Science channel. They know what they're doing. They're like, "Oh, you like to mainline this show? Yeah, we're gonna give you a taste. We're gonna give you a taste." They're not gonna put it all on at once yet until they run everything, so over the course of three different Saturdays, beginning February 9, February 23 and then March 9.

Chuck Bryant: Yeah, starting at noon. On all three days you're gonna see a couple of new episodes each time and then some reruns -

Josh Clark: Which we like to call classics.

Chuck Bryant: And then, in the final day - is it March 9?

Josh Clark: Yeah.

Chuck Bryant: - you're gonna see the lost pilot episode, which we can't believe is gonna be on TV.

Josh Clark: For better or worse. You get to see that one, yeah, the lost pilot.

Chuck Bryant: Yeah, and you can also - if you guys don't have Science Channel or don't have cable or whatever and you watch your TV on your computer you can get it on iTunes, you can get it on Google Play, you can get it on Amazon Instant. And the first episode is free on iTunes. And I know if - this is US iTunes and stuff and guys, if you don't live in the US we are working hard to make this available in other iTunes all over the world.

Josh Clark: It's important to us that you see it, too. So just hang in there. We're doing what we can.

Chuck Bryant: We're doing what we can. So thanks for the support. Watch it. It's funny stuff.

Josh Clark: Yeah, and if you just need to get your fix of Stuff You Should Know all the time you should go to our website, It's got our podcasts there. It's got our blog there. It's got all sorts of fun videos. It's very cool, so check it out.

Chuck Bryant: Great, okay. Get down to business.

Josh Clark: Get down to business. Hey and welcome to the podcast. I'm Josh Clark. Charles W. "Chuck" Bryant is breathing on his glasses, which means it's time for Stuff You Should Know.

Chuck Bryant: Is that what that means?

Josh Clark: Yeah.

Chuck Bryant: It means my glasses are just a little dirty, always. I think I'm just greasy.

Josh Clark: It happens.

Chuck Bryant: As a human, I just grease things up everywhere I walk.

Josh Clark: Everybody who wears glasses gets their glasses greasy.

Chuck Bryant: Really?

Josh Clark: Yeah. If you don't I mean what? You're like a lizard or something. You don't want that. You wanna make your glasses greasy. It's a small price to pay for having hydrated skin.

Chuck Bryant: Got you. That should be a t-shirt.

Josh Clark: I'm sure it will be in the near future. Are you doing good?

Chuck Bryant: I am doing well, sir. I enjoy these kind of topics where we hit on some nice environmental things that can help the environment.

Josh Clark: Same here. This one's beautiful, elegant in my opinion.

Chuck Bryant: And I apologize straight off for everyone that was cringing when we couldn't pronounce the river in Paris, France.

Josh Clark: The Seine?

Chuck Bryant: The seen, the sin or the sane?

Josh Clark: The sign. One of those three.

Chuck Bryant: Our friend and mortal enemy, Joe Randazo hates us now because of that.

Josh Clark: Of If you haven't, check out go because they're certainly watching you.

Chuck Bryant: Yeah, some of the former onion folks from New York split off and made this comedy website and we're gonna be on it soon, but we'll let you know when that happens.

Josh Clark: Yeah. It's an Adult Swim website, too, right?

Chuck Bryant: Yeah. So despite the fact that Joe is angry at us and - what did he say? How can you guys be adults in the world and not know how to pronounce that?

Josh Clark: How do you not know how to pronounce the Seine?

Chuck Bryant: Yeah. I'm like, "Dude, I'm not Mr. Fancy Pants. I'm not in Paris every other week like you." All right.

Josh Clark: That's our Joe. Let's see. I've got some horrifying stats for you.

Chuck Bryant: Oh boy.

Josh Clark: Eye opening, to say the least.

Chuck Bryant: Okay.

Josh Clark: Did you know that one third of the global food supply goes to waste?

Chuck Bryant: Wow.

Josh Clark: 1.8 billion tons around the world of food go to waste. What's interesting is it's not just developed countries. Developing countries waste about as much food per person as developed countries do.

Chuck Bryant: Really?

Josh Clark: Yeah.

Chuck Bryant: I wonder if they waste though because they can't help it because they don't have the refrigerators and the storage that we do.

Josh Clark: I don't know.

Chuck Bryant: And here we just toss it away like so many discarded business cards.

Josh Clark: Well, there's a - wow, I was not expecting business cards.

Chuck Bryant: I was trying to think of something you just get and throw away.

Josh Clark: You know what? Anyone listening to this podcast, if you were expecting Chuck to say business cards email him right now and let us know.

Chuck Bryant: Yeah, and also, please don't ever give me a business card. And if you have in the past I apologize.

Josh Clark: There's a little dirty secret among grocery stores where if a fruit or vegetable, produce it's called collectively, doesn't really look quite right, but is totally fine, examples I've seen is like a slight bruised tomato or something like that or a carrot that's not straight enough, they just throw it away.

Chuck Bryant: Yeah, we've covered that in something. I can't remember what.

Josh Clark: It seems like we have, haven't we?

Chuck Bryant: Yeah, it's sad. They should have a -

Josh Clark: I wanna bring it out into the light again.

Chuck Bryant: Well, they should have a misshapen fruit and vegetable store where you can buy a crooked carrot that tastes just as good.

Josh Clark: Or like one of the drawings from The Far Side owns and operates the store. Do you remember the people? They had crooked heads and everything.

Chuck Bryant: I bet people would buy that stuff though. If you don't have as much money you might wanna buy a tomato that has a bruise and just cut that little part off.

Josh Clark: Sure.

Chuck Bryant: Just a thought.

Josh Clark: I think it's a good thought. So 1.3 - I think I said 1.8, but 1.3 billion tons of food is wasted every year. That's just food, dude. In 1960, the average American generated 2.68 pounds of waste a day. Today we're up to about 4.6 pounds a day.

Chuck Bryant: You know what it is in Chicago?

Josh Clark: What?

Chuck Bryant: You know how we mentioned Chicago in this article as being overrun with garbage?

Josh Clark: Yeah.

Chuck Bryant: In 2010, the average Chicagoan produced 15 pounds of waste - 15.4 pounds per day.

Josh Clark: How is that possible?

Chuck Bryant: I don't know. And I think we're up like - I think Chicago is up 300 percent from the 1980s. So I don't know what's going on there, but they're like double what they are in the state of Illinois period.

Josh Clark: That is really nuts.

Chuck Bryant: Yeah, it is.

Josh Clark: I'm really curious what's going on there. What are you guys doing?

Chuck Bryant: What are you guys doing?

Josh Clark: So overall, we're producing apparently, most of it from Chicago, 230 million tons of waste in the US every year. And there are some programs that are set up to where somebody who runs a landfill where all this stuff is going and decomposing and producing methane and they capture that methane, burn it off or save it and use it for productive stuff or there's also things called waste energy facilities that just burn trash and then the heat from that incineration powers - creates steam that powers turbines that generate electricity.

Chuck Bryant: That make business cards.

Josh Clark: That you throw away. The circle of life is complete. So there are programs in place that make productive use out of trash that's just gonna be trashed anyway, but like the waste energy facility that's just burning trash, that generates a lot of horrible stuff, horrible pollution. There are actually programs that are even better that could someday be used to power our cars through garbage.

Chuck Bryant: That's pretty awesome.

Josh Clark: Yeah.

Chuck Bryant: And of course, this article starts off with a little Back to the Future reference. How can you not talk about garbage fueling cars without mentioning Mr. Fusion?

Josh Clark: So you thought about that, too?

Chuck Bryant: Yeah, immediately.

Josh Clark: I told Jamie what we were doing. She's like, "Oh, like Back to the Future" and I was like, "Yeah. Really? Of course." I love that movie, but that's not what I think of with garbage powered cars because I forgot that he even does that.

Chuck Bryant: Oh, to me, that was a big impactful scene at the end when he comes back in the spaceship, cracks open the Mr. Fusion and puts a beer can, an old beer and a banana peel in there. I was like, "Oh man, is that what the future's gonna be like?"

Josh Clark: And the answer's no.

Chuck Bryant: Well, not too far off maybe.

Josh Clark: Well, let's talk about the - how Steven Spielberg got it wrong.

Chuck Bryant: That wasn't Spielberg. It was Robert Zemeckis.

Josh Clark: He produced it.

Chuck Bryant: Did Spielberg produce it?

Josh Clark: I'm pretty sure he did.

Chuck Bryant: You just wanna blame him for everything.

Josh Clark: I've got a beef.

Chuck Bryant: A Spielberg beef. All right, so gasification is what we're talking about and it is actually possible in this day and age, right now today to create liquid fuel that you can burn in your car from garbage.

Josh Clark: Yeah. The basis of this is something called syngas or synthesized or synthesis or synthetic gas, but everybody calls it syngas for short. And it's the product of I guess accelerated decomposition.

Chuck Bryant: Yeah, from what they call feed stock, which is basically just your source fuel. And in this case, feed stock can be everything from asphalt and sewage, fossil fuels, of course we know about to plastics, biomass and Ag waste and garbage, municipal solid waste.

Josh Clark: Yeah, as long as it's not metal or glass and it's carbon based it will - you can make syngas out of it.

Chuck Bryant: That should be in your recycling bin people.

Josh Clark: Yeah, that old bed frame of yours, recycle it.

Chuck Bryant: But wood - if it's wood - oh, you mean the metal bed frame.

Josh Clark: Yeah. You know, that cheap one that always - it's like -

Chuck Bryant: It's so hard to put together and -

Josh Clark: You pinch your fingers.

Chuck Bryant: It's the worst.

Josh Clark: Yeah, it's bad news. So the process of creating syngas uses not combustion, but intense heat; way more heat than it would take for a normal combustion. I think 2600 degrees Fahrenheit and about 1,000 pounds of pressure, but it's in a very low oxygen environment, so the stuff doesn't ignite. It doesn't burn. It undergoes a chemical reaction called pyrolysis.

Chuck Bryant: Yeah, the key here is heat without flame or one of the keys. And this is not new. This sounds like the future, but back in the 1600s in Belgium they were using wood and coal to power street lamps and it was called town gas. And they did this also during World War II during fuel shortages. They made syngas from wood chips and powered vehicles using them. So it's not like a new thing.

Josh Clark: No. And apparently, Apartheid-era South Africa did the same thing because they were under international sanctions -


Josh Clark: They were cut off from the rest of the world.

Chuck Bryant: Remember that?

Josh Clark: Yeah. What was the dude from the East Street Band? He was the consultant -

Chuck Bryant: Bruce Springsteen?

Josh Clark: No, the other guy.

Chuck Bryant: Clarence Clemmons?

Josh Clark: No, the other guy.

Chuck Bryant: Steve Van Zandt?

Josh Clark: Yes.

Chuck Bryant: Little Steven.

Josh Clark: He's who I associate with don't play "Sun City". He was a big proponent of that, wasn't he?

Chuck Bryant: I think he was, too. And then he did The Sopranos and forgot about "Sun City."

Josh Clark: And now he's the consultant of the guy who did The Sopranos "Ode to being in a garage band" in the 60s.

Chuck Bryant: Yeah, I wanna see that.

Josh Clark: I heard it's good.

Chuck Bryant: Yeah, it's supposed to be awesome.

Josh Clark: Okay. So you take your feed stock, which is - what we're specifically talking about is garbage today. You take your garbage, say your banana peels and you wanna dry them out because that's how it goes. You put them in this thing called a gasifier, which depending on whether you make one at home, which there's videos on YouTube for how to make them or you could go down to Tampa and see one that provides power for 60,000 homes.

But a gasifier is this low oxygen, high pressure, high temperature environment that produces pyrolysis. That chemical change, that chemical decomposition where this carbon based feed stock, the volatile chemicals basically separate from it and it becomes this thing called char. And the char is further reduced to carbon monoxide and hydrogen. And that is syngas.

Chuck Bryant: And that syngas alone could power certain types of vehicles. I think the Honda Civic NGV and apparently, there are - in Toronto, of course, in Canada - they're always doing great things like this - they have garbage trucks and buses, I think. Or no, maybe just garbage trucks that run on compressed natural gas. So you could actually fuel it with syngas. In order to use that fuel more widespread, you have to convert it to ethanol.

Josh Clark: Right. And there's a company that's interviewed in this article "How Garbage Powered Cars Could Work" -

Chuck Bryant: Coskata?

Josh Clark: Yeah. I guess that's how you say it. And they take syngas and they feed it to a bunch of bacteria in a vat of water.

Chuck Bryant: That's amazing.

Josh Clark: And these bacteria, equally amazing, are patented. That's kind of disturbing. I don't think life forms should be patentable, but yes, it is a patented bacteria that eats syngas and then expels ethanol. And then they add a little gasoline to the ethanol to denature it so they don't have to pay a $27 a gallon liquor tax.

Chuck Bryant: Yeah, that's amazing to me. It's almost the same thing as moonshine until you denature it. So they said, "Add a little gas to it and we don't have to pay that liquor tax, spirit tax."

Josh Clark: Right.

Chuck Bryant: How much is it, like - what'd you say?

Josh Clark: It's like $27 a gallon.

Chuck Bryant: Wow.

Josh Clark: Yeah. And they're producing a lot of ethanol, as much as they can. That's a lot of extra money they don't have to pay just from adding a little gasoline. And then what you have is engine grade ethanol ready to be mixed with gasoline, which if you go to a gas station there's a pretty good chance you'll see a sticker that says "This gas may contain up to 15 percent ethanol." So your car that you're driving now can run on the syngas created from garbage, or if you have a flex fueled car that can use up to 85 percent ethanol, 15 percent gasoline. So it could use even more of the stuff.

Chuck Bryant: Don't they have ethanol only pumps?

Josh Clark: Yeah.

Chuck Bryant: Like ten or 15 percent they say are ethanol only?

Josh Clark: Oh, is that right?

Chuck Bryant: I think so. I might be wrong there. They may be flex fuel with just more ethanol.

Josh Clark: I've seen - I have seen ethanol, but I've seen flex fuel more frequently. And then you see that 85/10 mixture, 85 gas - or 15 percent ethanol mixture almost everywhere.

Chuck Bryant: Yeah. That's how I screw up every weed eater I've ever had because you have to mix the oil and the -

Josh Clark: Yeah, the two-cycle stuff.

Chuck Bryant: Oh man. I always do it wrong.

Josh Clark: I remember that. I used to be like, "Lawn boy, why are you so difficult?"

Chuck Bryant: So one of the things you wanna do here is - well, first you gotta separate all the garbage. That's one of the problems, but you want stuff that's uniform and stuff that - if it melts it's not good apparently, so even though you can use things like diapers for gas and ethanol - it's pretty awesome - what you want is something more like wood, something carbon based that will just sort of disappear when it gets hot.

Josh Clark: Right. And wood is probably the best feed stock for syngas because apparently, it leaves about two percent char behind and the rest is - the rest becomes syngas. And it's not all syngas. There are other things, especially - even in wood, something as pure as wood, there are impurities. If you're burning PVC, plastic there's a lot of impurities, but the beautiful thing about using a gasifier to produce syngas from any kind of feed stock is it's this closed system and you can control and separate all those different chemicals and impurities out. So you just have pure syngas, which when burned burns at a really high temperature. So it has almost no emissions when you use just the syngas.

Chuck Bryant: Yeah, and that's no matter what feed stock is originally used.

Josh Clark: Exactly.

Chuck Bryant: Zero emissions, almost zero.

Josh Clark: Yeah, because whatever feed stock you use you can sort these impurities out. And in some cases, you can reuse the impurities, like if you use discarded tires apparently, there's 188 million scrap tires just sitting around in the US breeding mosquitoes, catching fire randomly for eight months -

Chuck Bryant: Tire fires.

Josh Clark: Yeah. They've figured out that they can tires, scrap tires as a feed stock for syngas. And even cooler, after the syngas is separated you still have that char leftover; you can use that and it's more efficient than regular coal.

Chuck Bryant: Really?

Josh Clark: Yeah.

Chuck Bryant: Wow.

Josh Clark: So there's really not too many downsides to creating syngas because you're - especially if you're using it as - if you're using garbage as a feed stock because it was gonna go to waste anyway.

Chuck Bryant: True. That's a good point. And I don't know if you'd count them as problems. There are some setbacks. The reason why this isn't so widespread is that there are setbacks, like you gotta sort through this waste. You can just go to your landfill and dump a truckload of garbage. You have to separate it and make sure it's the right kind of stuff. So that costs money.

Josh Clark: You have to get rid of the bed frames, the glass, all that stuff.

Chuck Bryant: Yep. And you need to get it fairly uniform. So there is some money and cost involved in the preparatory stages that probably, I guess, aren't feasible right now in a widespread manner.

Josh Clark: And then there's also the thing - we've talked about this plenty of times whenever we talk about energy - the net energy ratio. You want more energy put out than you put into it. Or else, it's just not viable. And apparently, a study of bio fuels found that almost all of them require more energy.

Chuck Bryant: Really?

Josh Clark: The lowest they found was 27 percent more. Sunflower oil apparently, a bio fuel based on that requires 100 percent more.

Chuck Bryant: Wow.

Josh Clark: So you have to put in two to get out one or one to one.

Chuck Bryant: So that's the battle then, to keep making that smaller and smaller.

Josh Clark: Right, but the beauty thing with syngas is that's not necessarily the case. Now, I don't know about this company - what is it, Coskata?

Chuck Bryant: Yeah.

Josh Clark: What - how much more energy it requires for them to turn that syngas into ethanol. And if there's a net energy loss or a gain or what, but if you're just burning syngas it's very elegant, it's very clean and there's - I think it's a net energy gain.

Chuck Bryant: Awesome. Well, one of the other problems is you gotta dry it out, too. You can't throw - you can use waste materials like biomass, like leftover pulp and stuff from wood mills, grass and corn, but that's moist. So you have to remove the moisture, which is gonna cost a little more money. And then the article mentions, too on the other end, you're gonna have a little issue with ash, producing too much ash.

Josh Clark: Right, depending on what you use.

Chuck Bryant: Yeah. So that's like what you said, wood is the good because you only produce about two percent. But if you're not using wood you're gonna have leftover ash to deal with.

Josh Clark: But like we found with tires, burning old tires, you have that stuff leftover and sometimes it can be useful depending on what you're doing with it.

Chuck Bryant: That's true. And I know they recycle the water used in the little bacterial process, which is kinda cool.

Josh Clark: Another advantage of creating syngas is - I read this study that found you can take CO2 and inject it into a gasifier and it actually produces more syngas, more carbon monoxide.

Chuck Bryant: Oh really?

Josh Clark: So if you can sequester CO2 from say a regular coal fire power plant and bring it to a syngas plant you can use it for that, to convert it into something useful rather than just polluting it.

Chuck Bryant: Interesting.

Josh Clark: Yeah, isn't it?

Chuck Bryant: Yeah. And I think that this stuff, the more you work toward these problems the cheaper it's gonna get. One of the reasons that petroleum is the way to go is because we've been using it for so long and it's become one of the more cost efficient ways to fuel a car. It may not seem like it these days, but they've got the process down pat because they've been doing it for decades. Think about 50 or 60 years from now where we might be with some of this stuff.

Josh Clark: We'll be using bananas and beer, just putting it right into our car.

Chuck Bryant: You never know. How about this dude, Chip Beam? Did you look this guy up? He's the guy that -

Josh Clark: The trooper?

Chuck Bryant: Yeah, he took an old Isuzu Trooper and basically cut the rear covered portion out to where it has a pickup bed and has a big kettle there where he burns wood chips. And he has been running this '88 Isuzu Trooper on wood for quite a while now. 45 miles an hour is the top speed. That's not too bad.

Josh Clark: Yeah, it's good city speed.

Chuck Bryant: Yeah, it's a getting around town car. And apparently, it's the original engine. He didn't have to modify the engine at all. And it smells faintly of charcoal barbecue.

Josh Clark: That's really interesting that he didn't modify the engine.

Chuck Bryant: Not in the least bit. Isn't that crazy?

Josh Clark: Wow.

Chuck Bryant: And he's working on a Mercury, a '91 Mercury Cougar. His goal is to make the fastest wood burning car in the world. So it gets 45. he wants to go like 70.

Josh Clark: Doesn't that just evoke images of Granny Clampet on a rocking chair on top of the Clampet family car?

Chuck Bryant: Yeah. I like this guy though. That's pretty awesome.

Josh Clark: I do, too, but I had a question about his setup. So if you're creating syngas in this closed environment, you're able to trap impurities and use them or sequester or do whatever with them to keep them from entering the atmosphere. If you're creating syngas as you're burning it, what kind of emissions are there from that? I had a question about that.

Chuck Bryant: I don't know. I bet we could get in touch with Chip Beam.

Josh Clark: Well, let's do it.

Chuck Bryant: He seems getable. You got anything?

Josh Clark: No, I think that's it. We touched on everything. Stop wasting food. What is wrong with you?

Chuck Bryant: Stop wasting food. Yeah, I think that's everything.

Josh Clark: Okay. If you wanna learn more about garbage powered cars, energy, all that kind of stuff, you can type any of that into the search bar at Also, try typing gasification into the search bar. That'll bring up a pretty cool companion article that we worked off of as well. And I said search bar, which means it's time, of course, for listener mail.

Chuck Bryant: That's right, Josh. I'm gonna call this yet another librarian email unless people don't wanna hear from librarians anymore.

Josh Clark: I think that'd be a good charge.

Chuck Bryant: I've read a couple. This makes three. "Guys, I graduated from library school in May and started to work in a small university library in South Texas. Like many librarians, I've always been very passionate about banned books and censorship. While in library school, I was the president of my university student chapter of the American Library Association. Our group decided to sell t-shirts as a fundraiser.

Several of the officers created design ideas and we asked students to vote on their favorite before we started taking orders. The majority of the students voted for a design including quotes from out of copyright books, including many frequently challenged or banned books set over a drawing of an open book. I sent out several emails to students to promote the design and started taking orders. After receiving several of these orders I received an email from a student who was upset about the design. He was most upset about a Kurt Vonnegut quote.

I don't want to get into the specifics of the email, but I was appalled that a library school student wanted to censor our library school group. As librarians, we are obligated to provide information, not limit it. We ended up using quotes about intellectual freedom, the freedom to read and censorship in libraries to appease the nay sayers. I'm still bitter about the entire situation and can't wait to hang up my banned books week posters on my office door." So her plan, Megan's plan for banned books week is to read as many of them as she can and encourages everyone to do the same.

Josh Clark: And to eat the traditional banned book week's Swedish meatballs.

Chuck Bryant: That's right. So cheers from South Texas from Megan. And enjoy those banned books and Swedish meatballs.

Josh Clark: Yeah, thanks a lot, Megan. Thanks to everybody who celebrates banned books week. If you have a suggestion for a banned book, your favorite banned book we wanna hear it. We'll tell everybody about it. Let's just get talking about it, okay guys? You can tweet to us at syskpodcast. You can join us on, you can send us an email to and you can visit our home on the web

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Duration: 26 minutes