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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.
When he mentions it being 'disruptive', he's referring to the concept of disruptive technology as written about in The Innovator's Dilemma by Christensen:
http://www.amazon.com/Innovators-Dilemma-Revolutionary-National-Bestseller/dp/0066620694
Great read, and the concepts are laid out here:
http://en.wikipedia.org/wiki/Disruptive_technology
If you're not familiar with the concept, it's worth checking out.
This should have been called a "Think Village", because 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. Seriously, just start counting off 6.5 seconds right now.
An old-timer with old-timey ideas.
Wonder no more
"A Stirling engine is a closed-cycle regenerative heat engine with a gaseous working fluid."
As with many of these hybrid and electric car announcements, it'd be great if I could really go buy one, and have it be inexpensive. We're always just "2-3 years" away from these things reaching market, and "eventually" being affordable by regular folks.
Perhaps some Indian or Chinese company will make these and sell them here for under $10k. That would spark a huge revolution. Hybrids at $24k don't change people's buying habits enough to cause a huge shift in demand.
For better or worse, I think we'll see an alt-energy evolution in the US, rather than a revolution.
creation science book
For those of you who do not know what a Stirling engine looks like, Wikipedia has a very detailed diagram.
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!
Ford Think: Top speed, 55mph; 0-30, 6.5 seconds; Range, 60 miles on battery.
0-60, never. :-(
The problem isn't the top speed being less than 60 mph. The problem is that as vehicles get close to top speed they tend to be less responsive to the accelerator.
With a top speed of 55 mph, this is relegated to situations where you know you will never end up on a highway... Heck, most cities have some highways in them (I know that Manhattan, New York, has a couple where you can legally go 50mph and sometimes see people hit 75mph).
Help! I'm a slashdot refugee.
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
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.
But here is the deal... this is a START. Better things are coming. There are other ways to hybridize a power train. Several really good ideas for recovering energy that is typically wasted in current vehicles will help, _more_ efficient engines help, better battery technology helps, more efficient solar cell technology helps, more efficient electric motors helps, and most of all a populace willing to accept smaller more efficient vehicles will help. It will take time to put it altogether and make it usable.
You should not be expecting a revolutionary vehicle or power train technology to come along next Tuesday at 2:37 p.m. It will take time. If instant success at the end goal of technology were possible we would not be following Moore's Law at all. We would simply have leap-frogged to the end-game technology. Let's not even go to that thought that alien technology would help if the government would release the information from Area 51. I'm quite happy that there are folk working diffidently to create things that will help us arrive at the end goal - very efficient modes of travel. Note that automobiles are not the only place that improvements can be made.
Safe and ridiculously cheap is what you will not have for a while yet. They will get there. There are private groups working on electric and hybrid cars as well as very cheap cars. The no one you speak of are the same people that think driving a hummer or huge pickup is ok since it only costs a few dollars more. Not everyone has those 'few dollars more' to waste.
Safety? Are motorcycles safe? If there were far fewer SUV's and other big vehicles on the road, safety issues change a bit. No vehicle is safe enough to drive head first into a concrete bridge upright at 70 MPH. Safety is a subjective word and ideal. If you want to drive around in a tank, I'm pretty sure that more than 50% of the populace is okay with you having to pay quite a bit extra for the privilege. Good luck with that.
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http://www.telegraph.co.uk/earth/main.jhtml?xml=/earth/2008/10/27/sv_deankamen.xml
I read several articles on this when news first broke. The above indicates the Stirlin isn't even connected. When it is, it doesn't produce enough power to actually move the car. Kamen has a 1KW Stirling that is about the same size as what is pictured and other articles mentioned it as a "trickle charger".
In this case the Stirling is essentially a novelty, it doesn't drive the car when the battery is run down.
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.
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.
Well, I'd say his inventions such as the portable dialysis machine, the auto-syringe technology for people who require round the clock injections, and the wheelchair that can climb stairs made a tremendous difference. These medical inventions restored a reasonable standard of living to a great number of people, and are the foundation of his current fortune.
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?
I'm looking forward to being able to toss a couple armfuls of firewood in the trunk of my car and running errands.
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.
People who need to drive 150 mph can get a powerfull sportscar - maybe even one that'll only do 2 mpg flat out.
Nobody wants a sports/race car that only gets 2 mpg.
Gasoline is heavy. And energetic. Better fuel efficiency means you can carry less of it, and get more (speed) out of it.
Admittedly, sports cars are relatively wasteful, since they are tuned for maximizing speed. But this necessarily involves maximizing the amount of energy extracted from fuel, which is the SAME goal econo-car makers are trying to achieve. Econo-car makers are only getting there now because of a LOT of engineering by Honda, Toyota, Porsche, Ferrari, etc 10 years ago.
After all, I am strangely colored.
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.
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The Stirling engine is pretty neat. It'll run on hot air.
If we install a bunch of them in Washington DC, the energy problem of the US will be solved for good.
It's not. "Minutes" isn't a problem at all for ER-EVs. Gas turbines integrate quite nicely. They take the time that they need to to start up and can run for a dozen minutes or two, then they shut off. DesignLine busses use Capstone microturbines for this very purpose. The Capstones use an air suspension so that the shaft encounters nearly no friction. As a consequence, they have very long lifespans.
Mr. Wizard... why is this place called the Cave of Hopelessness?
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
Don't forget the water purifier. Kamen went on Colbert and showed off a system that can extract pure water out of essentially any stew, and is robust and cheap enough to use reliably and distribute throughout the the third world. His demonstration was pulling good water out of, I don't know, raw sewage or something, and he was drinking it.
When Colbert made his characteristic sarcastic remarks about not being able to see the point, Kamen responded that 50% of the deaths in the third world could be traced back to water-borne diseases. With this machine, he said, we could save the lives of millions of people per day.
Until that moment, I had thought that he was the self-promoter-yadda-yadda of the GP poster, but his concern and contemplation of the possibilities seemed genuine and sincere. I'm not going to buy a Segway any time soon, but man, but hats off to him if his inventions really do save lives.
FWIW, Colbert had a sip, too.
The CB App. What's your 20?
The strength in Stirling's design is that it's effective at scavenging heat energy. So rather than powering it directly, why not use a traditional ICE or turbine for charging the batteries and then use the Stirling to scavenge energy like subject of this /. article:
http://science.slashdot.org/article.pl?sid=05/12/15/0037238
Maybe even take it step further and put the Stirling downstream of the steam engine?? With modern alloys and using freon or gaseous ammonia instead of water, you can greatly improve your efficiency.
33cc is optimal for the piston size/stroke which can be oversquare (stoke is longer than piston diameter). or undersquare (stroke is shorter than piston diameter).
Longstroke = more torque, short stroke = more power at high rmp. - Just scale it up if you need bigger.
Your problems will be the heat exchangers - very efficient at heating water btw.
Wiki has a good description and will give you a few types to consider.
There's what you want already built in Spain: Point focus parabolic dish with Stirling engine and its solar tracker at Plataforma Solar de AlmerÃa (PSA) in Spain.
http://en.wikipedia.org/wiki/Sterling_engines
There are also other 'solid state' alternatives too.
Just google it to find a pile of hobby sterling engine sites.
There are also commercial sterling fridges, water-heaters and power generators ready to go.
Don't be apathetic. Procrastinate!
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/
Lending seems a bit trickier.
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
Stirling engines used in military system have the advantage that cost is almost irrelevant, but Stirling for road vehicles has the chicken and egg problem - to prove the viability of the concept, you need to get up to big manufacturing volumes to get the reliability data and drive costs down. The takeover by Diesels for cars in Europe was made possible because the technologies for advanced Diesels were already in wide use in marine engnies and just had to be engineered down the size scale. This situation does not exist for Stirlings.
On the pollution front, it is true that Stirling engines will burn most fuels, but the downside is that it is very hard to produce a multi-fuel engine that does not produce a lot of soot from some of those fuels. You can drive a small Sitrling by burning wood - if you don't mind dismantling the heat exchanger periodically to get the gunk out.
Kamen's idea is, I feel, less about viable technology than pressing buttons with the US Government's priorities. It would be more economical, and more reliable, to fit a small off the shelf packaged generator of the sort that is already available to fit into boat lockers. Compare the price of one of these with a Whispergen and you will see the point very quickly.
From scarped cliff or quarried stone she cries "A thousand types are gone, I care for nothing, no not one."
Then you have to convert that 23% into a useful form of work (let's say electrical energy) which incurs additional efficiency loss.
Not that there's anything wrong with that... using an extra 5 or 6 percent of the chemical energy in the fuel for useful output still counts, but there is a pretty high cost in money and weight associated with getting that extra energy out. If it's done in a vehicle you have to account for the decrease in acceleration efficiency due to the extra mass...
Less is more.