I've seen a lot of people talking about the impact cars have on the environment, and most seem to be pretty unhappy about it. What I'd like to know is what you think can be done about it.

I'm gonna tell you about something you may or may not have heard about before. There's a new type of internal combustion engine being developed that's not made out of metals, but ceramics.

I'm an engineer, so forgive me if I start to bore you. Ceramics in general have some wonderful properties that modern material science is just beginning to be able to take advantage of. They're extremely tolerant to heat and are just about the best insulators imaginable. They can be cut and shaped to extremely tight tolerances that are impossible for metals, and do not corrode like metals. They can have extremely low coefficients of friction and be very light and hard at the same time.

Prototypes of ceramic engines have been made, and the results are incredible. Because of their tolerance of heat, they can burn 3 times hotter than a metal engine... hot enough for motor oil to act like a clean-burning fuel, and producing practically NO pollution with regular gasoline. In addition, they need no coolant system (no radiator), and because they can be cut to very tight tolerances (parts can be made to fit within several microns of distance) no engine oil is needed. They're so efficient that a ceramic engine, when compared to a regular 4-stroke engine of identical size, will produce 250% of the horsepower using approximately 25% of the fuel. They can easily weigh 50% to 80% less.

A batch of 10 of these engines, with 1 liter displacement, producing 500hp each, has been created by the Germans and have been extensively tested. The longest one has been run the equivalent of 1,200,000 miles and still shows no signs of wear and tear.

So what's the catch? First of all, ceramics are extremely brittle. A collision that would put an irrelevant dent in a metal engine would destroy a ceramic engine. Second, nobody's set up to build these things en mass, so for now they'd be extremely expensive. Third, if released, the face of the oil industry would completely change. Potentially thousands of people could lose their jobs, and the Middle Eastern and South American countries would no longer be sitting on the enormous piles of wealth they currently enjoy.

But when the problems are worked out by the coming generation of engineers, and when these engines catch on, do you understand the impact they will have?

And now think about this: ceramic engines were developed by a relatively small group of people who got together and pushed the limits of technology. A few people here and a few people there have created something which may forever dramatically change the world for the better. This kind of thing is not uncommon in engineering... a single person with a single idea can make more of a difference than all of the legislators in the world.

I know there's a lot of younger people on thise board, and I guess I'm trying to say, if you really care about the world you're living in, and you have the dreams, the creativity, and the dicipline, study hard, learn as much as you can, and be one of the people who changes the world. What can you do to really make your world a better place?

I don't know anything about engineering, but could they possibly encase the ceramic engine in metal, to protect it from a collision? Or would the impact shatter the ceramic?
I hadn't heard about this. do you think it will be big enuf to make the news in Canada any time soon?

> hot enough for motor oil to act like a
> clean-burning fuel, and producing practically
> NO pollution with regular gasoline.

There's something i don't get here. The engine still burns normal gas, right? How can you burn fossil fuel and NOT create carbon dioxide?? No matter what temp, if you burn something carbon based, you get CO2. Or is there some kind of nuclear "melt-away the atoms" chemistry going on here?

Superjane:
The problem is that the metal would transmit the force through it, and it would still be enough to shatter the ceramic. That probably doesn't make sense, but think about it like this. If you put a dozen eggs inside a steel egg carton, and then hit the carton with a hammer, what would happen if the steel egg carton got dented just a little? The egg inside would break.

The ceramic engine is still little-known and news about it tends to travel around tight engineering circles. If it got any public coverage, it would probably be in magazines like "Popular Science".


Oatmeal:
CO2 isn't a toxic pollutant. If it was, we'd all be dead right now. When methane and other carbon-chain molecueles are burned in the cleanest way possible, you'll get CO2 and water. If the reaction isn't complete, you'll get CO, nitrogen oxides, and leftover hydrocarbon emissions.

You and every other animal on the planet spews out CO2 in massive quantities. Every plant at night will spew out CO2 as well. But when the sun is shining, every tree, every clump of moss, every tiny cell of algae, every green leaf with chloroplasts in it will guzzle CO2 and vent off the waste fumes: that highly reactive, highly corrosive, highly unstable gas called oxygen.

Well, CO2 is not a toxic pollutant, but a pollutant nonwithstanding. You said "producing practically NO pollution" and that's why I asked.

Thanks for the clarification!

I still wouldn't call it a pollutant. A pollutant is some form of waste matter which contaminates the environment. Carbon dioxide doesn't contaminate anything because it's already there and gets readily absorbed by plants to be turned into oxygen.

i think they should market the ceramic engine as a great advance in safety, imagine, an engine the disintegrates upon impact, thus allowing more give in the frame work and allowing less human killing collisions. Its all how you spin it. ;)

Yeah right.

Burning petrol without pollution ? In an engine ??

This has nothing to do with ceramic parts.

Imho there is no real future for the internal combustion engine as we know it.

"because they can be cut to very tight tolerances, no engine oil is needed."

Parts might be close to eachother but it doesn't mean you don't have to grease them.

Besides I find it hard to believe that (full) ceramic valves can stand the forces.

It might be an interesting side step, just like the car that runs on air, but I don't see a future for it.

Note: CO2 might not be toxic, but is (said) to be a contributor to the global warming.

Transport in cars as we know it now will be gone in 60-100 years.

Also see this http://www.veggieboards.com/boards/showthread.php?s=&threadid=3533&highlight=gas+prices page 2 and further.

"hot enough for motor oil to act like a clean-burning fuel, and producing practically NO pollution with regular gasoline. "

"and because they can be cut to very tight tolerances (parts can be made to fit within several microns of distance) no engine oil is needed."

If no motor oil is needed, what is the point of mentionng that motor oil would act like a clean-burning fuel? What motor oil. You're not making sense there.

Why would close tolerances reduce the need for friction-reducers (and therefore simultaneously heat-reducers), like oil?

You also haven't addressed an important quality of metal engines, which is that distances between moving parts change, as the engine heats up. Metal expands. Holes get bigger in diameter. Round things inside the hole get bigger in diameter. Whichever gets hotter gets "more bigger." Ceramics, with the same changes in temp, don't change in size as much -- but we are talking about greater changes in temp. You haven't explained what is going on here.

You say ceramics don't corrode. But corrosion inside cyclinders and around valves is not generally a substantial problem with metal engines. The corrosion problem is in the cooling system that is water-based, where the water is in contact with metal. Since you say the ceramic engine has no such cooling system, then lack of corrosion would not be relevant.

What kind of wear are moving ceramic parts subject to? Do ceramic internal comb engines have piston rings? What are they made of? I'm trying to imagine ceramic pistion rings. Can't do it.

I don't see the kind of spring-loaded valves that are on metal engines, working on ceramic engines. A few smacks against a valve seat -- and goodbye valve head. The valves would seem to require a completely different design.

I am familiar with ceramic combustion chambers -- in hydronic heating systems -- with a steel boiler sitting on top of a ceramic combustion chamber. The ceramics are very fragile. They can take extra-ordinary amounts of heat -- but if you are not careful cleaning the inside, you can easily ruin such a comb chamber with a cleaning brush, or a plastic vacuum-cleaner tube. You don't want to drop the unit when transporting it, either -- crackded, ruined, sort of.

Indeed, they are lightweight. But they are softer even than a styrofoam cup.

If i were designing machine with ceramic moving parts, I would tend to be thinking more along the lines of high-temperature plastic resins with ceramic fillers, rather than plain ceramics. Like epoxy-ceramic composites. Much less brittle than plain ceramics. Can have some flexibility without breaking or cracking so easily. That's what I have in my molars. Work out better than either silver-amalgum fillings, or plain ceramic fillings. Tho not as good as gold fillings.

Why, by the way, have external combustion engines, steam engines, been entirely replaced by internal combustion engines?

Good question. Long preheating time?

Are stirling engines more efficient users of fuel than internal combustion engines? If so, the might be better engines for vehicles that run on air pressure stored in an air tank (cars that operate the way air-tools operate). Stirling engines don't have good accelleraton, but this is not relevant where you would be keeping the enging alternating between running at one most-efficient speed, and off, as needed to top off the pressure in the tank. And why don't we see them on air compressors?

Steam eninges have a very low fuel efficieny.

IIRC:

Steam engine 5-10%
Petrol engine 30-40%
Diesel engine 35-45%
Big (BIG) Boat engines up to 50%

Imho they change in design will not cure the problem of the limited amount of oil left in earth.