[Dean Kamen]’s company, the people behind the Segway, have created a hybrid car that uses a Stirling engine instead of a standard internal combustion engine. Stirling engines are closed cycle, meaning heat is applied to the outside of the cylinder walls. They are generally more efficient than standard car engines, but haven’t been used much outside of industrial applications. We suspect that the drivetrain arrangement is similar to the Chevy Volt where the engine is used to charge batteries which are in turn driving an electric motor. This is different from modern hybrids that can have either electric motor or gas engine driving the wheels. The article is unfortunately full of classic [Kamen] hyperbole and minimal detail. He calls the Stirling engine “an insurance policy” for the electric car since it can recharge the battery. That’s right, folks. If you run out of juice, you can put gas in the car. I doubt many Prius owners will fall out of their chair over that. Being a Stirling engine, we’d be more impressed if you could charge the thing by rubbing warm toast on it.
[via Make]
I’ve often wondered why no one has investigated the benefits of other types of internal combustion engines, particularly the ones that recycle the heat that is wasted in the typical four stroke.
Carnot, mother f***ers
>instead of a standard internal combustion engine. Stirling engines are closed cycle, meaning heat is applied to the outside of the cylinder walls.
Well… they *are* closed-cycle. What that means is that the working fluid does not escape: they don’t breathe like most car engines do. What was meant by ‘heat is applied to the outside of the cylinder walls’ is that these are external combustion engines: the hot (and cold) parts of the engine are heated (and cooled) externally. In a standard internal combustion engine, the heat is generated inside the engine.
Can’t believe I laughed when I first opened that sterling engine article on wikipedia.Thought I was looking at a *completely* different page.
Still at the bottom I found this link to Stirling Engine using waste heat to power fans for CPUs. Seems like it would make more sense to reverse the engine and use it as a heat pump. Steampunk Xbox 360 anyone?
http://global.msi.com.tw/index.php?func=newsdesc&news_no=591
this is really cool, if i got my hands on blueprints i would make a car of my own. and then show you guys how i did it. i honestly never thought of putting that in a car. i got a small sterling for my wood stove to run a fan, but i never thought car.
1 step closer to Perpentual motion! Whaahahahahaaha…..
Of course, the best thing about having a Sterling engine in a car, is that it can run on anything that will burn properly. Gasoline, diesel, just about any type of oil, even wood and paper should work, if a suitable combustion chamber is fitted.
Also, this thing doesn’t care about impurities in the fuel; it doesn’t suffer from detonation problems, or fouling of values and such.
What about solar heat? Cant you just focus it on the engine and have it rolling ?
I’ve seen some people set up a small sterling engine at the focal point of a solar collector to run a generator, so yes.
of course the problem then lies in those in places like england and washington state as the severe lack of quality sunlight will pretty much keep the car at a dead halt.
First thing I though of was the little engines you used to be able to get from edmund scientific.
(R.I.P.)
My first question was where we were supposed to find 300 tiny cups of sterno!
Of course, then there’s the fact that a gas cycle (like the sterling cycle) kinda sucks for efficiency relative to a steam cycle; we use gas cycles because you can make them lighter and they start quicker. But if you’re running a serial hybrid like this one, you don’t care if the combustion engine takes a minute or even a few minutes to get up to speed, and you aren’t exactly trying to make it airborn, so the mass matters less if you get efficiency to compensate. I keep meaning to try to get an estimate on the size of a steam engine capable of producing the average power consumption of a car…
jonored, I only have one reply:
steam powered robots.
@strider,
http://www.crabfu.com/steamtoys/
Perhaps I just plain missed it, but it would have been nice to see more details or videos of the car in operation. After the hype Kamen put out there before revealing the Segway, it’s hard for me to take him seriously. However it would seem it finally dawned on him most of the public, needs an efficient motor vehicle capable of more than one passenger, and carrying cargo.
I have a sneaking suspicion this car’s range decreases by an order of magnitude if you run the A/C (if it has any). And that would also explain why Kamen’s only potential investors are in Norway.
About four years back a company called ANUVU in Sacramento California was showcasing fuel cells on the show; the screensavers and showed a prototype of a sterling engine at the focal point of a 8′ satellite dish with a generator running a 3.5k generator. I have tried for the last five yours to find out about where I could get one or make one. To no avail. Just point it at the sun and electricity!
I wonder how good the durability of the Sterling engine is? That’s always been the sore point for Sterlings. To operate efficiently they need to run at very high temperatures, and that means they can’t use conventional forms of lubrication for the piston rings. The result is usually high ring and cylinder wall wear and a short running life.
The other sore point was always that they didn’t throttle well, but in a hybrid that’s not a big deal.
A sterling engine with a big solar reflector may not work in overcast areas, but photovoltaics will at about 80% of their normal capacity.
bigd145:
The last stuff I read with regard to dish-mounted stirlings was that, despite losses in the dish and mechanical losses in the both the stirling and the generator, the dish-mounted stirling was a *more* efficient producer of electricity than the best photovoltaic array (of equivalent capture area.)
stirlings, by the way, tend to run a *long* time without maintenance.
ac7zl
I would second bidd145 on that.
I am curious what kind of RPM they’re getting out of the sterling in that car.
Popular Mechanics just did an article about dish-mounted stirling engines for producing electricity. http://www.popularmechanics.com/science/research/4286850.html?page=8
Here’s another link to a full article on them.
http://www.popularmechanics.com/science/research/4288743.html
Warm toast won’t create or hold enough of a temperature differential, but if it’s especially cold outside and the enclosed piston is shaped properly, maybe you could sit on it…
…perhaps a bagel?
What?
wow..engine car..I saw it on wikipedia as well
Ive been building a few sterlings and they might work well in a car, i wonder if hes using a low or high temperature differential engine, i think cambridge had some powerful results from both.
id love to stick one on my karmann ghia
Just go to the Kamen patent website. It has all the details on how to make a Stirling engine.
i have been working on a car that is powered by solar energy and uses stirling engine to convert it into electrical energy.i am unable to find an appropriate stirling engine.can someone help me .i am looking for an engine that gives 600cc atleast.or 25 hp or more when converted electrically .my email id is akash_marshall@yahoo.co.in..please reply me if you have some idea related to it..