Can this poisonous weed be the biofuel that save us all?
Almost overnight, the unloved Jatropha curcushas become an agricultural and economic celebrity, with the discovery that it may be the ideal biofuel crop, an alternative to fossil fuels for a world dangerously dependent on oil supplies and deeply alarmed by the effects of global warming.
The hardy jatropha, resilient to pests and resistant to drought, produces seeds with up to 40 per cent oil content. When the seeds are crushed, the resulting jatropha oil can be burnt in a standard diesel car, while the residue can also be processed into biomass to power electricity plants.
Forget biofuels - burn oil and plant forests instead
http://environment.newscientist.com/article/dn12496-forget-biofuels--burn-oil-and-plant-forests-instead.html
The diesel engines you are looking at are the old technology indirect injection ones. Modern common rail direct injection diesels used in current passenger vehicles are a WHOLLY different animal entirely. The NOx emissions are slightly higher than gasoline engines, but the hydrocarbons and carbon monoxide are much better. With particulate traps and NOx aftertreatment, they have much better emissions than the toughest Federal standards. CO2 (if you believe in global warming) and fuel economy are better as well and the engines have much better torque than gasoline engines.
As for the noise issue with old-tech diesels, that comes from very high rates of combustion; electronic injection on modern engines allows the fuel pulse to be metered out more slowly, "rate shaping" the combustion. Works good! On common rail engines with electronic injection noise has been 90% improved -- you'd probably have to put the hood up to notice it's a diesel.
Modern automotive diesels produced in Europe are very nice engines with gobs of torque, good emissions, and excellent fuel economy. I wouldn't put on in a pure sports car like a Porsche (not quite as high revving as an Otto engine), but for even sporty sedans like Mercedes and BMW they are excellent. The key is common rail direct injection. Except for the few diesels sold by Mercedes and VW in the US (well, 45 states of the US), the rest of US Diesels (pickups and big trucks) are old tech and not too impressive. If you stuck one of the modern diesels in a very light car like a Honda Insight (throwing out the stupid hybrid powertrain), you'd wind up with a lighter, cheaper, better performing, and handling car that gets comparable fuel economy. A side benefit of diesels is that they are relatively easy to run on all kinds of kooky bio-fuels like this bean juice. The Diesel cycle is a lot less fussy than the Otto cycle as to fuel properties. That doesn't mean biofuels are "the answer", but the diesel cycle is more efficient to start with and more amenable to alternate fuels -- it's a better place to start.
Re: Diesel engines. If they're so great then why do they stink so much, release more soot and particulate than regular gasoline and cause engines to be noisier?
If you've spent any time in a country like England which seems to adore diesel fuel then try taking a day trip to London, then at the end of the day (sorry for the icky description) blow your nose to find nasty black residue in your Kleenex.
I am not interested in a nice head nodding conversation. But polite? Why not? We can disagree to our core and have great conversations doing it. People resort to insults in online situations when they most likely would not do so face to face.
My reference to polenta was simply a responce to JC's statment concerning corn: "corn isn’t meant to be eaten by humans. There’s a reason why it cannot be digested by our immune system."
I supose my overly dramatic response was unwarented, but I was making a point.
While you feel that my refrence to HFCS was made from a soapbox, I vew it simply as fact. HFCS comes from corn and is eaten, digested and matabolized by humans. North Americans consume massive amounts of the stuff. Calories + sedintary lifestyle= Fat. (Too simplistic?)
If you want argue that HFCS is not a major contributing factor to obesity. By all means please do.
This is from the neatoroma post (above)
"...with the discovery that it may be the ideal biofuel crop, an alternative to fossil fuels for a world dangerously dependent on oil supplies."
My only argument is that biofuels, in all their varied forms and abillity to fill niches, cannot REPLACE oil at current rates of consumption for the reasons I stated above. Large scale reliance on biofuels is not viable.
Beyond that, I agree whole-hartedly with your last paragraph.
Yes, any of the bio-fuels that are so "hot" these days would require a LOT of land be devoted to their production. Some of them (like corn for ethanol) are a lot worse than others, though. These are complete dead-ends and aren't worth wasting time, effort, and $ on. The problem with government tinkering in the form of subsidies and tariffs is that it sends people off working on losers. If free market forces are left to their own, the best solution(s) will win.
And that is what I was getting at with regard to vehicle mass. The gov't has imposed so many regulations that cars have gotten very heavy which KILLS fuel economy. People should be free to choose whatever car they want. A cheap, light fuel sipping one or a large, heavy, crashproof one that sucks gas like mad. Let the market decide.
And no, diesels are not a savior, but the fuel efficiency advantage of the Diesel Cycle over the Otto Cycle is undisputed. It's time for the U.S. gov't (and California which has their own standards and largely drives the boat) to end their bias against diesels. For large fuel chugging vehicles like SUVs and Pickups, the availability of common rail diesel powertrains would be an awesome option.
Pax teum.