It's About Liberty: A Conservative Forum
Topics => Science, Technology, & Medicine => Topic started by: BMG on May 05, 2012, 09:43:35 PM
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The 100 MPG automobile (http://www.americanthinker.com/2012/04/the_search_for_the_100-mpg_car.html)
In 1986, when gas was selling at the pump for a dollar, NASA decided it would begin a project to improve the fuel efficiency of the automobile. This project was known as the Stirling Automotive Engine Development Program.
It seems that one of the bright rocket scientists decided to apply the properties of an engine under consideration for spacecraft use to the automobile; the result was a Stirling Cycle engine. As an external combustion engine, it is fundamentally different from the IC engine. This type of engine configuration burns fuel in a burn chamber to heat a motive gas, not unlike a fire grate, which heats the steam in the boiler of a steam engine. The result is that this engine uses the portion of a gallon of gasoline that has the most energy: the heat generated from burning the gasoline.
NASA was able to achieve 58 MPG by replacing the IC engine in the Chevy Celebrity with a Stirling engine with a 38% overall maximum efficiency; more than twice that of an IC engine. Although this project had impressive results, it fell short of the Holy Grail of 100 MPG. As an example of typical government behavior, the successful program was therefore shelved with no further development.
Fast-forward to the 21st century and look at one of the attempts to achieve the 100-MPG car. The Automotive X Prize originally solicited competitors to design and build a production-line vehicle that could achieve 100 MPG. The winners were essentially motorcycles with composite frames, all of which used the IC engine.
However, a search of the Patent and Trademark Office does hold a glimmer of hope that we will not all be riding a motorcycle with a side car in 2025. The Holy Grail of 100 MPG seems to have been found in Texas. The approved patent, for a Stirling Hybrid Electric Automobile, has seemingly doubled the efficiency that NASA achieved by changing the design. The inventor, Mr. McDowell, has introduced a heat exchanger that converts the hot exhaust gas directly into electrical current, which is fed back into the hybrid electrical system. The design is much like that of the Toyota Prius, except that there is a Stirling engine and not an IC engine. This invention proves once again that the private sector is better at this Grail Quest than government.
Look, I don't mind energy saving devices that WORK. To date we really have nothing that works - solar panels on a small scale but that's about it. If this works, great! Boy, you sure have to wonder though - if 58MPG was possible in 1986 why have we been going through all these contortions all these years concerning fuel efficiency? Could it be that politicians would have lost a major tool from their tool box that helps them manipulate voters if this had been pursued back then? Seems to be the likely scenario to me. As with most everything political; it never was about the 'energy' but it always was about the 'power'.
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Umm, okay but what kind of HP is achieved? I'm guessing it's pretty darned low...like lawnmower type low.
No one wants to drive a riding lawnmower to work and back even if it gets 100 mpg.
Well almost nobody (http://en.wikipedia.org/wiki/The_Straight_Story) wants to drive a riding lawnmower.
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Umm, okay but what kind of HP is achieved?
No one wants to drive a riding lawnmower to work and back even if it gets 100 mpg.
Well almost nobody (http://en.wikipedia.org/wiki/The_Straight_Story) wants to drive a riding lawnmower.
Stirling Engines main problem is HP. You can buy toys that run off the heat from a cup of coffee- of course all they can turn is a little paper pinwheel. I did a lot of research on these in my quest for power. There was apparently a decent version produced in Asia ( Thailand?) but the company went out of business in the 80s. You could still buy plans online though.. I would be more interested in using one of these as a generator than as a car..
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Stirling engines have been around since Stirling invented his in 1816. If a Stirling were a useful alternative to an internal combustion engine, it would have made its mark in the market long ago. Unlike an internal combustion engine that actually converts potential energy (in the form of fuel) into kinetic energy, a Stirling engine only converts kinetic energy (thermal, or heat) to kinetic energy (rotary motion). It is able to achieve a high degree of efficiency in doing so, but is not well suited for applications that require uneven applications of torque, like driving a car, because its output doesn't respond very quickly to changes in input, ie, it doesn't "throttle" very well.
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Stirling engines have been around since Stirling invented his in 1816. If a Stirling were a useful alternative to an internal combustion engine, it would have made its mark in the market long ago. Unlike an internal combustion engine that actually converts potential energy (in the form of fuel) into kinetic energy, a Stirling engine only converts kinetic energy (thermal, or heat) to kinetic energy (rotary motion). It is able to achieve a high degree of efficiency in doing so, but is not well suited for applications that require uneven applications of torque, like driving a car, because its output doesn't respond very quickly to changes in input, ie, it doesn't "throttle" very well.
In a hybrid the Battery bank supplies the energy burst needed for Torque.. But the article suggests exhaust heat fuels the stirling - exhaust form what? A diesel or gasoline engine? Or are they just burning gas for direct heat? If your heat source is a Gas engine..then this is a normal hybrid, but with heat recovery. Neat, and more efficient, but not ground breaking.
As usual the problem is the battery bank. We just don't have a decent cost effective means of storing electric energy. That is why large scale wind and solar don't work competitively- like the Stirling in this car they can provide an assist, but its fossil fuels that keep it all going.
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Stirling engines have been around since Stirling invented his in 1816. If a Stirling were a useful alternative to an internal combustion engine, it would have made its mark in the market long ago. Unlike an internal combustion engine that actually converts potential energy (in the form of fuel) into kinetic energy, a Stirling engine only converts kinetic energy (thermal, or heat) to kinetic energy (rotary motion). It is able to achieve a high degree of efficiency in doing so, but is not well suited for applications that require uneven applications of torque, like driving a car, because its output doesn't respond very quickly to changes in input, ie, it doesn't "throttle" very well.
In a hybrid the Battery bank supplies the energy burst needed for Torque.. But the article suggests exhaust heat fuels the stirling - exhaust form what? A diesel or gasoline engine? Or are they just burning gas for direct heat? If your heat source is a Gas engine..then this is a normal hybrid, but with heat recovery. Neat, and more efficient, but not ground breaking.
As usual the problem is the battery bank. We just don't have a decent cost effective means of storing electric energy. That is why large scale wind and solar don't work competitively- like the Stirling in this car they can provide an assist, but its fossil fuels that keep it all going.
Yep, it's that "fossil fuels" thingie there that makes mobility possible.
We could, I suppose, go back to horses...but the air pollution from dried, ground up horse manure is a much more difficult public health problem to deal with than soot. At least soot is generally sterile.
Too bad, 'cause I like horses.
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Umm, okay but what kind of HP is achieved? I'm guessing it's pretty darned low...like lawnmower type low.
No one wants to drive a riding lawnmower to work and back even if it gets 100 mpg.
EXACTLY!! I'm not about to sacrifice my get up and go for mpg. I've tried driving those vehicles you need a calender to time them on the dragstrip and they DON'T work for me!
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Really?
Road testing a Stirling engine powered buggy, (filmed in Norwich England, 2001) (http://www.youtube.com/watch?v=qS5x91CZbtY#)
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I think I'll hold out for the "GT" model - the one that has brakes and a suspension :o
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Really?
http://www.youtube.com/watch?v=qS5x91CZbtY# (http://www.youtube.com/watch?v=qS5x91CZbtY#)
Woman @ 2:31 feigning excitement at traveling 3 KPH on a flat surface: "Ha-ha-ha! Woo!"
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I think I'll hold out for the "GT" model - the one that has brakes and a suspension :o
::beertoast::