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Dean Kamen Combines Stirling Engine With Electric Car
Colin Smith writes "Dean Kamen, (inventor of the Segway) has combined a Stirling engine with a battery-powered electric vehicle based on the Ford Think to provide a fully decoupled electric hybrid car which can run on any fuel which can provide enough heat to run the Stirling generator. Think are also producing a purely battery 'Think City' car which is capable of 62mph and with a range of 126miles." Some stats on the Ford Think: Top speed, 55mph; 0-30, 6.5 seconds; Range, 60 miles on battery.
It's been refined for 160 years plus change. So it ought to be really spiffy, right? Well, no. There are definite upper limits to the efficiency of such a device. Most Stirling sites are very cagey when it comes to mentioning the efficiency of what they're selling. For good reason, it's terrible. Like 3 to 6 percent. That kinda explains why it's not in use everywhere, more like nowhere.
Great acceleration and no range. I don't care if it takes me 12 or 20 seconds to reach 60mph if I can go 300mi/charge, with the heat, headlights and windsheild wipers on.
Like I just did yesterday.
Gone!
stirling engines are ridiculously safe. And if you mass produced them on the scale that typical car engines are mass produced they would have to be a fraction of the price. I don't agree that it's a good design to go with, but I can't argue with the price for the components.
“Common sense is not so common.” — Voltaire
I seriously don't know how Th!nk plans to stay in business with the City versus some of its competitors. Say, the Aptera, for example.
Seating: 2 or 2+2 (Th!nk City); 2+1 (Aptera)
Trunk: 6 cubic feet (Th!nk City); 15.9 cubic feet (Aptera)
Top speed: 60-65mph (Th!nk City); 85-90mph (Aptera)
Accel: 0-30 in 6.5 seconds (Th!nk City); 0-60 in less than 10 seconds (Aptera)
Range: 110 miles (Th!nk City); 120 miles (Aptera)
Charge time: 10 hours at 230V/14A (Th!nk City); 8-10 hours at 120V/15A or 2-3 hours at 240V/30A (Aptera)
Construction: Plastic, aluminum, steel (Th!nk City); Layered composite monocoque (Aptera)
Insurance category: Car (Th!nk City); Motorcycle (Aptera)
Purchase price: $20-25k + $150-$200 per month battery rental (Th!nk City); $27k (Aptera)
Seems a no-brainer to me unless you're one of those people who don't like the Aptera's looks (I think it's one of the most beautiful cars I've ever seen). I'm getting an Aptera :)
Mr. Wizard... why is this place called the Cave of Hopelessness?
Why don't the inventors of these various electric cars do some basic sums? If you're going to have any sort of hydrocarbon fuel involved then use the most efficient conversion possible to electric power given the space constraint of a practical vehicle. Right now that's a fixed-speed diesel engine at approaching 50%. All these 'exotic' heat engines like Stirling etc. are dead in the water when it comes to basic thermodynamic efficiency. If you don't start with a reasonably efficient conversion you are not going to end up with a vehicle that is even slightly practical.
Small and light doesn't have to mean unsafe. Example: rollovers. Not only are big, topheavy vehicles like SUVs more likely to roll over, but they're also more likely to crush their occupants. Big and heavy means more weight trying to crush the roof. Furthermore, more modern materials can reduce weight while *increasing* strength./ I am legally prohibited from stating what I've seen in regards to the Aptera, but I'll just point out that there's a video on YouTube of an Aptera employee slamming a large hammer into the vehicle's shell with absolutely no damage. Go try that with your car sometime and see if you get the same results. Lastly, big and heavy often means less maneuverable which means more likely to get into an accident. There's this strange notion in this country that accidents are inevitable, so you better armour up; however, greater maneuverability and lower stopping distances means lower odds of getting into an accident in the first place.
Mr. Wizard... why is this place called the Cave of Hopelessness?
Ah, yes, the horrors of a car that won't fulfill EVERYONES needs. How about this - the people who drive more than 60 miles in a day can get another car. Maybe one with a bigger range.
People who need to drive 150 mph can get a powerfull sportscar - maybe even one that'll only do 2 mpg flat out.
People who need to haul a ton of stuff could get a different kind of car. Maybe one with a nice big flat section where you'd have the rear seats. Maybe a "flat bed" of sorts.
The people who have a need to drive 6 kids and their dogs every day could get something like a bus, but smaller. Miniature bus of sorts.
And maybe people like you could start to consider that there is no car in the world, that fulfills EVERYONES needs at once.
Exactly. On the one or two times per year that I need a truck, *I Rent One*. I don't keep a truck around at all times for the offchance that I might perchance need one. Why do people feel the need that they must have a vehicle that can do everything when they'll mainly just use it for their daily commute?
Mr. Wizard... why is this place called the Cave of Hopelessness?
Offtopic, but related to your sig: AC comments aren't anonymous when logged in. Try posting as AC while logged out, then moderating your comment.
blog & fiction: jd87
I met the guy and talked to him for awhile at a medical tradeshow when he had a really cheap 10 foot backwall booth and the most amazing piece of gear on the whole show, beat the snot out of all the big blinkenlights booths and their stuff, the go most anyplace crawling, climbing wheelchair thing. He's opposite of marketing, just thinks 18 miles away from some box all the time..then builds it and it works. Whether or not it sells marvelously or not, the dude is a rare man, a combination far out pure research scientist and practical engineer, he figures out how to make sci fi stuff actually work. Our society *demands* marketing and short term megaprofits though, so he's stuck sometimes. He's the kind of guy just needs some billionaire to adopt him as a pet project and turn him loose, so he doesn't need to worry about funding ever again. If even one out of ten things he makes really takes off, I mean to the general public and outside of medical specialties, yes, it will be worth it.
Because if they don't have one, it makes them dependent on others when they need one. And there are many people who can't handle that.
A fair number of my co-workers are amazed that I'll drive a small car for my daily commute. When I ask they why they use a massive pickup truck as their commuter vehicle, it's "in case I need it", or some BS about not being able to afford a smaller commuter car while keeping their large truck. For them, knowing that they have a massive four-wheel drive truck at their disposal at all times is worth the cost.
For me, I make them feel good about themselves by asking to borrow it when I need a truck. Nothing is more manly than being able to help someone with your massive truck. It's the reason you bought it, right?
Velociraptor = Distiraptor / Timeraptor
space has a cold side? what would that be - the vacuum? like what you have for a fucking brain?
Ignoring your manners for a moment, yes it can be said that space has a cold side. If you have an object facing a source of heat (the Sun, for example) then you will have roughly half the object in shadow. The shadow-side surface will be receiving no incident heat from radiation, yet will be able to exhibit cooling by thermal radiation. Thus, a "cold side".
Now, go back to your day job, which no doubt involves waiting under a bridge and shaking down travellers for coins.
Do not mock my vision of impractical footwear