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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.
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.
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?
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