Coming Soon to an Automobile Near You: Plastic engines?
Automakers and consumers alike all want lighter cars. "Adding lightness" has a lot of desirable effects, most notably in overall fuel efficiency and performance. While numerous efforts have been made to reduce the weight of automobiles – including downsizing, subtracting unnecessary components and using lightweight alloys and carbon fiber for structural bits – one item that's awfully hard to lighten without dire consequences is the engine.Well, perhaps that's not entirely true after all. Apparently, Matti Holtzberg, an engineer and president of Polimotor Research, successfully designed and built a working engine made almost entirely from plastic. Holtzberg created a motor based on the 88-horsepower powerplant from a Ford Pinto that reduced weight from 415 pounds to just 152 while putting out an impressive 300 horsepower.
Polimotor has reportedly partnered up with the Huntsman Corporation of Houston in an effort to get plastic engine components such as the block, cylinder heads, pistons and rods into mass production. While electric motors and high-tech batteries seem ready to take over in the coming decades as the power sources of choice, plastic engines could potentially still be used as lightweight range-extending powerplants. Intriguing, no?
[Source: New York Times via The Kneeslider]
Reader Comments (Page 1 of 2)
Turbofrog 6:29PM (10/31/2009)
Can those numbers possibly be correct? 1/3 the weight, and 4 times the power? That power/weight ratio is better than high-end motorcycle engines, and into the realm of pure racecar.
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wincros 11:49PM (10/31/2009)
Yawn. Another miracle of the future article from Popular Science that will never happen. It is not like the car manufacturers have ignored the possible use of plastic in engines. It is the norm for intake manifolds for at least a decade. If they could find other reliable uses it would have happened already.
rob 10:40AM (11/01/2009)
This particular "Pop-Sci miracle of the future" looks to be dated from 1982. So maybe the future has finally arrived...
As for the savings, if you just replace the engine with a plastic block then you've only captured a tiny bit of the benefit. Since your engine block and transmission are significantly lighter, now everything else in the front end of the car can become smaller and lighter as well. Which allows you do downsize the engine and keep the same performance, but drop multiples of the original amount of weight reduction. You can run around that design cycle a few times and what you end up with can be significantly different than where you started.
Of course, the automakers have huge investments (some would call it sunk costs) in metal casting and machining and are very resistant to changes. So I'm not going to hold my breath...
Treehugger 6:44PM (10/31/2009)
hope they can successed because plastic asides of being lighter has many advantages over metal : can be made from renewable source instead of mining the environemement, requires much less energy to be made, shaped than metal, can be transformed in fuel after use with 100% conversion efficiency instead of being dumped in junk yard. Also a block engine in plastic would retain heat much better than metal, which means that your engine can stay warm during many hours betwen use and then being less polluting and consuming less when restarted. Cold start are a disaster in term of emission on efficiency. BMW is seriously looking at that by the way
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Matt 1:57PM (11/01/2009)
I know what you're thinking, but it's just not that simple. Most metals are 100% recyclable, steel being the most recycled material in the world. Furthermore, the earth is made of lots of elements (see: Periodic Table), one of which is Iron. Iron is superabundant and all you have to do to get it is dig it out of the ground and heat it up until it melts. Steel is made primarily of Iron and also contains Carbon (one of the most abundant elements). That said, we're not running out of steel. Aluminum is another basic element that mother Earth is kind enough to provide in great quantities. As a matter of fact, Aluminum is more abundant than Iron (~8% of the earth's crust). The problem is, Aluminum alloys are much harder to turn into useful goods, thereby making the finished product more expensive.
Plastic is relatively easy to work with, but in terms of wear resistance and strength it's a looser. Sure, there are some composites that can compete with metals in strength, but durability is always an issue. I also think the 100% recyclable claim is off, or at least needs to be modified. SOME plastics are 100% recyclable, but not all; it's a broad range of materials. SOME plastics are carcinogens, SOME plastics contain contain harmful elements such as Cyanide or Volatile Organic Compounds. Most plastic will burn, it's just a matter of how hot and the presence of a spark.
I'm not saying this is not a good idea or it's not possible, but it's just not as simple as Plastic=good, Metal=bad. We need more information... which they will never give out.
Nick 6:55PM (10/31/2009)
What kind of plastic is being used?
How does the engine handle heat?
Friction?
Lubrication?
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Chris M 11:30PM (10/31/2009)
Apparently, the cylinder sleeves, cylinder head, valves, and piston head were metal, to withstand the high combustion temperatures. The plastic components were made using high heat resistant plastics, there are several that can withstand temperatures over 300 degrees F (148 C), and a few that can function up to 500 degrees F (260 C).
Cooling is by conventional circulating water/antifreeze solution, and oil cooling might also be used.
Oil is used as a lubricant, and many plastics are inherently low friction. However, there is a possible problem with different thermal expansion ratios, polymers tend to expand more than metals when heated. If care isn't taken in design, that could cause parts to seize up, or loosen and leak. I had a kitchen mixer that would seize up after working several minutes, the problem was two plastic shafts in metal sleeve bearings that would seize up when hot, but work fine when cold.
Boyprodigy1 7:07PM (10/31/2009)
Obviously being that this is a prototype, it is as optimally tuned as it can possibly get (Hence the 4x horsepower), however, the weight reductions are real world mass production numbers which would be brilliant for a range extender for a PH-EV (listening GM/Fisker?). I see large potential for this!
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JSacharuk 7:12PM (10/31/2009)
Wikipedia has an entry. Apparently the plastic is a special kind of Thermoplastic called Torlon. The article concludes that the research was basically considered a failure, but doesn't say why.
http://en.wikipedia.org/wiki/Plastic_automotive_engine
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NeilBlanchard 8:18PM (10/31/2009)
Here's another promising type of engine:
http://www.greencarcongress.com/2009/10/michigan-state-university-receives-25m-arpae-award-to-build-wave-disc-enginegenerator-for-series-hyb.html#more
5X as efficient, 20% lighter, 30% less expensive, and perfect for serial hybrids
Sincerely, Neil
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gorr 10:23PM (10/31/2009)
It look very promising this wave disk engine.
This plastic engine too.... and plastic chassis.. and plastic wheels.
Boyprodigy1 1:05PM (11/01/2009)
What about a plastic wave disk engine?
Chris 11:17PM (10/31/2009)
Anyone remember the development into ceramic engines? If I'm not mistaken the problem was the durability but it ended up to be a lot lighter in weight.
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timmylil 11:32PM (10/31/2009)
Why is this allowed? how come this site does not have a mark as spam button?
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nrb 5:32PM (11/01/2009)
" how come this site does not have a mark as spam button?"
Click on the "!" button to report the offensive post.
Paul 1:13AM (11/01/2009)
Manufacturers have been talking about plastic and ceramic engines for decades. You'd be surprised how many engine parts are already plastic. Intake manifolds, rocker covers, water pumps but the material the ICE is built from doesn't make it any more efficient. If it's a petrol powered ICE running through a multi speed gearbox and differential it's never going to do much better than 15% energy efficient at the wheels.... The more people that know that, the more doomed to the scrap pile they are, alongside incandescent light bulbs that are barely 5% energy efficient.
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Dan Frederiksen 6:23AM (11/01/2009)
not gonna happen. I think it's easy to lighten an engine. the jackasses just doesn't do it. they don't think in weight. it's exactly the same as the weight of the car and the aerodynamics. they aren't even trying.
the forces in an engine aren't actually that great for many of the parts. I figure cylinder walls, top, shaftholder and piston could be extremely thin. I wouldn't be surprised if a properly built engine would weigh less than 25%. maybe as low as 10%. you could perhaps weave carbon fiber on some of the parts but not plastic.
like in all matters, they are just not trying... morons with a bad attitude..
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Kid Dynamic 9:30PM (11/02/2009)
Heh heh. Look who's talking. I'd love to see the research that you're basing these assumptions on.
Dan Frederiksen 11:26PM (11/02/2009)
it's about understanding. do you have mechanical engineering knowledge? if so look into the forces in a motor and compare to even soft steel material strength. draw a simplified motor cross section and do the math
3PeaceSweet 9:50AM (11/01/2009)
As a main engine an ICE has to run 100,000 miles over a wide operating range frequently from cold starts. As a PHEV range extender the engine would be providing about 1/3 of the power and runtime of a 'normal' engines duty. Also the smaller engine could be placed under the floor of the vehicle or on the rear axle allowing the overall vehicle shape to me more aerodynamic with a much lower frontal area.
It's also to see the DIY solar heater article on the front of PopSci, there are loads on plans online to make simple solar space heaters. There not going to replace your heating system but they can provide you with lots of free heat.
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