Dean Kamen Combines Stirling Engine With Electric Car 324
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.
stirling engine is a no-go (Score:5, Insightful)
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.
Wow. More of the same. (Score:4, Insightful)
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.
Re:*yawn* (Score:4, Insightful)
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.
Re:Think CITY?? (Score:5, Insightful)
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 :)
Re:stirling engine is a no-go (Score:4, Insightful)
It powers the features that would normally drain huge power from the battery, notably the defroster and heater.
Not much point being efficient at generating electricity etc. if its primary function is to generate heat.
Thermodynamics 101 (Score:5, Insightful)
Re:stirling engine is a no-go (Score:4, Insightful)
The efficiency of a stirling cycle engine is a complete NON-ISSUE! for one simple reason.
most stirling engine setups use WASTE heat. And that is the most intelligent use of the stirling cycle. turning waste into power.
so efficient or not. you're getting energy for FREE from something that is complete waste.
even 3% efficient is still 3% you got for FREE and worth it.
Too Slow (Score:3, Insightful)
Just by looking around on the road you can tell people are chomping at the bit to drive a tiny tin can looking car, especially if that car is also slow as hell. In fact, the less likely (real or perceived) someone with boobs will give it a second look, the better.
Wait, scratch that, the exact opposite is true.
How about something between the Tesla Roadster and the Smart car. A mid-sized sedan style vehicle that is a plug-in hybrid with a constant RPM diesel generator when needed. Or fuel cells whenever Hydrogen refueling becomes a reality.
0-30 in 6.5 seconds? Sheesh. Better buy a dorky bumper sticker right off the showroom floor. This will give the people waiting behind you at the green light something to laugh at while they try furiously to pass you.
Re:*yawn* (Score:4, Insightful)
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.
Re:Couple of things bother me... (Score:5, Insightful)
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.
Re:Couple of things bother me... (Score:5, Insightful)
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?
Re:Think CITY?? (Score:4, Insightful)
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.
Re:stirling engine is a no-go (Score:5, Insightful)
He just likes building neat stuff (Score:3, Insightful)
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.
Re:*yawn* (Score:3, Insightful)
Absolutely right on! Safety is not common sense in many cases. Look at F1 racing vehicles. They move at incredible speeds and consequently, when they crash it is a sight to behold, yet because their cockpit is designed with lightweight and very strong materials, drivers survive all but the most devastating of crashes. Those materials push up the cost of the vehicle, but if there are several million vehicles made every year with such materials, the cost of manufacturing with those materials will go down. Not even scifi dreamed materials will stop a guard rail from pushing it's way through the vehicle if you hit it head on. For pretty much everything else, there are safe ways to design a vehicle that will protect it's occupants at the cost of the vehicle's structure. You do NOT need to drive a tank.
I've thought of this quite a bit, and I think that Home Depot has the right idea to reduce some of the need for big vehicles. If you buy huge volumes of stuff from them, they will rent you a truck for $20 to take it home. So you can ride your bicycle to Home Depot and buy a fridge, and supplies to fence in your yard, rent a truck to get it home, then return and get your bike. This is one way to reduce the need for bigger vehicles. There are others that will help design around the problems of delivering bulk materials, transporting many passengers etc. It will take time, but we will get there. Every effort helps.
If one man, or one team should or could have all the answers, Thomas Edison would not have had to spend so much time perfecting his version of the light bulb. With that, here is a hat's off to materials scientists. They will find a material that is almost as light as plastic and has the needed strength to replace steel in vehicles. Situations like that the USA finds itself in right now will help drive the process of finding those materials. Please let's also not forget what kind of contributions that NASA and DARPA have given us, and can continue to give us if they are funded properly.
Fret not, good things will come our way.
Re:stirling engine is a no-go (Score:5, Insightful)
Re:stirling engine is a no-go (Score:4, Insightful)
Re:Couple of things bother me... (Score:4, Insightful)
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?
Use metric. (Score:1, Insightful)
Why the fuck is a high technology site like Slashdot still using Imperial?
I mean come on, you're nerds, people. Move to SI.
Re:Thermodynamics 101 (Score:3, Insightful)
Efficiency is defined by energy out over energy in, or power out over power in as the case may be. Power is the product of engine speed and torque. So, yes, with a CVT, you can pick the engine speed that's most efficient for given power output requirements, trading engine speed for torque. However, that's the most efficient speed *for the given power requirements*. That doesn't mean that the current power requirements are the most optimal for the engine.
But yes, I think the poster's point was a good one, that in a series hybrid, you can run an engine at near optimum performance -- not by merely picking an optimal speed, but an optimal speed * torque as well.
Re:Think CITY?? (Score:3, Insightful)
I have a wife and two small children, which one do I tow behind the Aptera in a trailer?
I have a wife and four children and I want an Aptera. Sure, it won't work when the whole family is going somewhere, but neither does our normal four-door sedan (Saturn Ion II). But the Aptera will be a great car for commuting, running to the grocery store (which is 40 miles away) and lots of other running around.
When we all go somewhere together, we need a vehicle that seats six comfortably. For that (and for camping, boating, hauling stuff, etc.) we have a Dodge Durango.
Different vehicles for different purposes.
Re:Think CITY?? (Score:2, Insightful)
To be fair, that's actually fairly acceptable in countries outside of the USA/Europe (for example, I'm in Taipei, Taiwan and in this country you are lucky to exceed 110km/h on the freeway (68mph). In many cities I've been to, cars rarely exceel 50 km/h in the city and 0-50km/h (50km/h = 30mph). Add to the fact that many cities are loaded with speed cams and the expensive price of gas, this is a perfectly acceptable city car or taxi.
Re:Couple of things bother me... (Score:3, Insightful)
That sort of resource sharing was pretty useful in the "village" days. Very limited resources, if not enough people were willing to work together, everyone was in big trouble.
If someone could work out a way to reduce the impact of assholes/crooks, it may well be that lot more people might be willing to share (lend) their massive trucks or other resources.
Currently there seems to be some progress in the "giving" of resources no longer used with stuff like: Freecycle- http://www.freecycle.org/ [freecycle.org]
Lending seems a bit trickier.
Re:Air Submarines And The Hunky Men Who Love Them (Score:5, Insightful)
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.
Re:Think CITY?? (Score:3, Insightful)
I doubt any large enough city will have traffic that is forgiving enough to allow a small electric car to reach 30 (either kph or mph) in 6.5 seconds.
There are plenty or large cites, from London to Bankok, where drivers are grateful to reach 30mph ever.
Re:stirling engine is a no-go (Score:3, Insightful)
If said wheelchair is your only hope of mobility, virtually any price is "affordable."
Re:Wondering what a Stirling engine is? (Score:3, Insightful)