"And when Henry Ford was experimenting with car engines a century ago, he tried ethanol out as a fuel. But he rejected it—and for good reason. The amount of heat you get from burning a litre of ethanol is a third less than that from a litre of petrol. What is more, it absorbs water from the atmosphere. Unless it is mixed with some other fuel, such as petrol, the result is corrosion that can wreck an engine's seals in a couple of years."If ethanol is so "ineffective", then why is there so much "talks" about it, and so much "excitements" about ethanol?
"the real reason ethanol has become the preferred green substitute for petrol is that people know how to make it—that, and the subsidies now available to America's maize farmers to produce the necessary feedstock."Other scientists, technologists know the "true costs" of ethanol as alternative fuel, so there are a few "real alternatives" perhaps in the making. Using the wonder of biotechnology, harnessing the power of enzymes and micro-organisms, even "designing" natural evolutionary processes in selecting the ultimate survivors, "enzymes that can perform chemical transformations unknown in nature", design of biopetrol is stirring interests due to its potential of having optimal mixtures of properties as motor fuel.
Other scientists are taking different approaches, they using synthetic biology that turns living organisms into chemical reactors "reactors by assembling novel biochemical pathways within them. Dr Keasling and his colleagues scour the world for suitable enzymes, tweak them to make them work better, then sew the genes for the tweaked enzymes into a bacterium that thus turns out the desired product. That was how they produced artemisinin, which is also an isoprenoid.
Isoprenoids have the advantage that, like alcohols, they are part of the natural biochemistry of many organisms. Enzymes to handle them are thus easy to come by. They have the additional advantage that some are pure hydrocarbons, like petrol. With a little judicious searching, Amyris thinks it has come up with isoprenoids that have the right characteristics to substitute for petrol."Even Craig Venter, the earlier pioneer in private human-genome project, is in the hunt for alternative energy. Though, like other venture capitalists he is for obvious reasons is reluctant to reveal his trade secret, but the rumors has it that he is shifting his strategies from hydrogen to liquid fuels.
The writer in The Economists surmises it correctly. Political backing for ethanol should be curbed down to give biofuels, that may prove to be many times more effective as "greener" alternative energy source than ethanol ever dream to achieve. The "political rush to back ethanol, just because it is green and people have heard of it, is a mistake."
Link to the The Economist article:
Another article on the same subject was published in National Geographic a few weeks ago. Here is the link to that article: Green Dreams.