Powering cars and busses by alcohol might be one way to get away from petroleum-based fuels. Yet, producing alcohol is difficult-you have to grow something that produces sugar, ferment the sugar, and distill the resulting alcohol. Why don’t we just use sugar? It is like alcohol,but with some extra carbon and hydrogen atoms. Suppose you were to vaporize the sugar=would it burn just as well? Of course, you would have a lot of carbon residue (possibly enough to foul the cylinders)?
Anyway, has pue sugar ever been used as a fuel for IC engnes?
I think probably the biggest problem is that the products of combustion include quite a good deal of solids, which is going to make the exhaust system difficult to engineer. There’s also the issue of unburned or partially burned fuel (=caramel) adhering to surfaces all over the place.
I don’t think it is possible to vaporize sugar, except possibly at very low pressures unsuitable for an IC engine. In normal conditions sugar will decompose if you try to vaporize it by heating. You will end up with some combustible gases and a carbon sludge residue.
He’s got a point though, everyhing that produced our hydrocarbons used sugar as fuel. And wound up with an energy surplus we harvest today.
Why eliminate the intermediate step?
I know, I know I took chemistry too.
But for you super smarties, why cant we?
I think you probably could. The problem would be that you would need a radical redesign of the engine and fuel delivery systems. It would cost a fortune and you would end up with a car which was less efficient, less reliable and less economic than a conventional vehicle. Less efficient because sugar (powderered or whatever) will have poor burning characteristics compared to petrol. Less reliable because a solid fuel system is a more difficult engineering problem than a liquid fuel system. Less economic because sugar is much more expensive than petrol.
Alcohol is the way to go. You can use it in a conventional engine without a major redesign. It is a better fuel than sugar. Also alcohol is not produced from refined sugar. Alcohol is fermented from sugar containing plants, avoiding the expensive and energy demanding process of sugar refining. Producing a kg of alcohol probably costs about the same and maybe less than a calorifically equivalent amount of solid sugar.
There’s no radical new design required, you have to revert to the older external combustion designs. Steam or Stirling.
That ain’t so. Ethanol is comparable in price to petrol (depends on tax situation in any particular country). Sugar costs less per available kJ to produce than ethanol.
Yes, that’s its major advantage.
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Sugar won’t vaporize, and solid fuel handling is a PITA.
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Sugar is already significantly oxidized, and won’t yield as much energy as hydrocarbons or even ethanol.
- Do we need a third?
I’m not sure, try putting sugar in your gas tank and see how well it runs.
Don’t, actually.