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Kids Build Soybean Fueled Sports Car
Sterling D. Allan writes "High school students from West Philadelphia High School have designed a sports car that can go from zero to 60 in four seconds and get more than 50 miles to the gallon on soy bean oil. CBS News reports that this unlikely car was the star last week at the Philadelphia Auto Show. Once again, are we seeing the fabled instance of revolutionary technology coming not from the big corporations, but from some unlikely garage. Maybe these guys will open source their design."
it should also be noted that their car is getting 50-miles-to-the-gallon with an engine big enough to do 0-60 in 4 seconds. cut that engine down for 80mpg, then hybridize it for 120mpg, and $9 a gallon for oil suddenly sounds a lot less (7.5 cents a mile as opposed to 8.3 cents for a 30mpg car at $2.50 a gallon for gas)
I have a plan for a truck that can drive thousands of miles on less then one gallon! Granted, it is a gallon of plutonium, but less then one gallon!
While it is commendable that these kids put together a working car that runs off soybean oil, this isn't a case of "the man" ((TM)) ignoring innovation for evil gasoline powered cars. Soybeans just are not competitive with gasoline. In fact, the entire idea of using crop land to meet our energy issues is a horrible idea in general.
Don't take me for a tree hugging hippy when I say this, but farming is a necessary evil. Don't get me wrong, I love farmed foods. I merrily buy my vegetables without bothering to glance if it is organic or not. I do recognize though that there is a price that comes with this. Very little land in the world can renew itself year after year. Farming by its very definition sucks up nutrients from the ground to be hauled off. Even organic farming is grossly destructive to the ground. More then one civilization in the world has simply collapsed because the soil died. There are entire continents, namely Australia, where there is absolutely no natural soil renewal. Farming almost always has a very high ecological cost. This isn't a trivial cost that we associated with other renewable energies like windmills where a handful of birds die. These are very serious nation threatening costs.
Certainly you can use fertilizers to keep the soil alive. With good farming practices like what are seen in the US and much of the first world you can keep the land fertile almost indifferently. Even so, these nations pay a heavy cost to keep their farmland fertile and watered. The environmental damage outside of the farm can be serious. When lesser educated farms in third world nations use these methods to keep the soil alive the result can be catastrophe for the environment.
We don't want more land to go to farming. We don't want more third world nations to burn down their trees to try and feed the agro business. Resorting to farming as a source of energy should be the last resort we fall back on, not the first. Algae, solar collector making, and wind power to make more fuel? Great. Creating a greater demand for farm land to make more fuel? Terrible idea.
So, congratulations to these kids for making a fun proof of concept, but this isn't the future of fuel.
It is a "glue" until alternative means (solar,nuclear,hydrogen,whatever..) can be built into the econemy. If we were to go completley (fossil)oil free today, there are so many cars and other machines that would be useless our econemy and possibly civilization would colapse. Soy oil and ethyl alcohols could keep these machines going until we can replace them with differently fueled vehicle or machines. The average car will last around 15+ years. After about 5 the first owner usualy gets rid of it and it changes hands until some poor sap gets it and it is the best they can afford and the cycle continues. After about 25 years, the car is probably scraped, recycled or preserved in some fasion were the transition from one type fuel to another totaly non dependent oil could be resonably done.
One of the most interesting parts of this article is the mention of sportscar and 50 mpg in the same sentence. Most if not all production diesel (soy bean oil's substitute)powered cars get less then 46 mpg. Some don't even get 25mpg if you count the trucks. Diesel fuel is said to have a higher amount of stored energy and is considered more efficient then soy oil. This same system getting 50mpg in soy might lend diesel fueled car the ability to get 60+mpg while still retaining performance.
For various reasons, diesels do not have nearly the efficiency penalty that gasoline engines do when operating at low loads. As a result, resizing the engine to be smaller won't really help that much. Plus most of the acceleration comes from the electric motor I suspect, just as it does with most other hybrids.
BTW, the main reason diesels are so much more efficient than gasoline engines is the way they are throttled. In a gasoline engine (Otto or Atkinson cycle), if the fuel burns too lean (too much air), the combustion temperature increases significantly and increases NOx emissions, and more importantly, tends to melt parts of the engine. The result is that to throttle down a gasoline engine, you can't just remove fuel - you need to remove AIR and adjust fuel delivery as appropriate, by essentially choking the engine's air supply. Thus at low loads the engine is essentially breathing through a tiny straw, and paying penalties in pumping losses.
Diesels, on the other hand, usually do not have any throttles in their air intake, they CAN be throttled simply by adjusting fuel supply. (I'm not sure why it is that they don't have to deal with lean burning, I'm guessing that one reason is that fuel is injected during the combustion cycle, rather than being premixed prior to ignition.) Since the engine never has to breathe through a straw (Although I think some large trucks do have options for switching a restrictor into the exhaust to allow for engine breaking), it can operate much more efficiently at low loads.
Diesels also happen to have higher peak efficiencies, but that doesn't affect choice of engine sizing nearly as much as the lack of pumping losses at low loads.
retrorocket.o not found, launch anyway?