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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."
maybe someone can fill me in, what's the end consumer cost of soyban oil per gallon and what are its chances of reducing in price (or more likely, increasing) when it's forced into a larger production?
This is a cute story, but really.. o Will this car pass crash testing? o Will this car pass emissions? If you don't need to pass crash test and emissions, heck...you can just put an engine on a go-kart and do 0-60mph in 4 seconds. This story is only a half-step above the recent perpetual motion machine stories.
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)
But modern diesel cars do take a conversion because they need to have synthetic tubing.
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also, the engine needs to be primed and heated, otherwise the oil is too dense.
But these are all petrol powered super cars. The fastest accelerating diesel I know of is the VW Touareg which reaches 60 in 7.5 seconds. Thats a big heavy 4 wheel drive, maybe if you took its V10 and dropped it into a light weight kit car it could do it in 4 seconds
If you try to build something idiot proof, someone builds a better idiot.
Incase you guys missed it http://www.philly.com/mld/inquirer/13796737.htm this isn't the first car like this and it's not a completely new or radical design.. it's just not popular yet
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?
potassium and phosphate, actually. Both are required for fruiting, but not needed so much for general plant growth.
A main component of healthy soil is the availability of organic matter in addition to the clays and sands. Growing a healthy root mass (as legumes do) improves the soil in just that way. Fixing nitrogen is a tremendous aid to that. Fixing nitrogen with bacteria is still better because it leaves behind a more complex matrix than ammonia and roots alone.
You're correct that it isn't a revolutionary project, and that it is missing lots of things.
I've seen this car, and have browsed hundreds of on-line photos of it's construction.
The chassis and body were a kit from an eastern European country.
The chassis is setup by the manufacturer to accept commonly available junkyard suspension components. I think the whole front end (steering, etc) is from a honda accord.
The front motor is a big honkin' DC motor mated to the accord transmission.
No regenerative braking here, just a MOSFET speed control and the accord's normal brakes.
The entire rear drivetrain is a bone-stock VW TDI motor and transmission. Sure, it runs on soybean oil, but so will my VW if that's what I fill it with. No magic here, just a junkyard motor.
It's got 100+ horsepower driving each end. Of course it's fast.
It's smaller and sleeker than my Jetta which gets 50mpg using the same motor. Of course it gets good mileage.
I'm sure those kids learned a heck of a lot, and I bet they're inspired to do keep up thier schoolwork so they can do more. That's the real story.
Interesting.... sounds a lot like this vehicle by San Diego State University Department of Mechanical Engineering HEV (hybrid electric vehicle) Team.
It also uses a AC Propulsions electric motor (200hp) (which is what the kids used) and a Volkswagon turbo-charged direct-injection diesel engine.
The SDSU site goes into great detail about other engine considerations and why they decided on what they chose based on scientific data and research.
The Internet Archive shows the site has been http://www.engineering.sdsu.edu/~hev/index.htm">ma inly unchanged since 2000, long before the kids started their project in 2003.
Did the kids give any credit to San Diego State University for pretty much stealing their entire concept?
my karma will be here long after I'm gone