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View Full Version : Ethanol-blend auto emissions no greener than gasoline: study



johnnymk
04-04-2007, 10:16 PM
This just confirms what has been reported earlier.

http://www.cbc.ca/canada/manitoba/story/2007/03/30/ethanol-emissions.html

An unpublished federal report appears to undermine the belief that commercially available ethanol-blended fuel produces cleaner emissions than regular gasoline.

Many Canadians believe filling up with ethanol-blended gasoline reduces the emission of greenhouse gases that damage the environment.

Advertising sponsored by the Canadian Renewable Fuels Association encourages the idea, telling Canadians renewable fuels are "good for the environment," and even some provincial governments, including Manitoba and Saskatchewan, say the fuel "burns cleaner" than gasoline.

The federal Conservative government committed $2 billion in incentives for ethanol, made from wheat and corn, and biodiesel in last week's budget.

But based on Ottawa's own research, critics say the investment is based more on myth than hard science.


Scientists at Environment Canada studied four vehicles of recent makes, testing their emissions in a range for driving conditions and temperatures.

"Looking at tailpipe emissions, from a greenhouse gas perspective, there really isn't much difference between ethanol and gasoline," said Greg Rideout, head of Environment Canada's toxic emissions research.

"Our results seemed to indicate that with today's vehicles, there's not a lot of difference at the tailpipe with greenhouse gas emissions."

The study found no statistical difference between the greenhouse gas emissions of regular unleaded fuel and 10 per cent ethanol blended fuel.

Although the study found a reduction in carbon monoxide, a pollutant that forms smog, emissions of some other gases, such as hydrocarbons, actually increased under certain conditions.

Bill Rees, an ecology professor at the University of British Columbia and longtime opponent of ethanol, has read the report and thinks Canadians need to know its conclusions.

"I must say, I'm a little surprised at that, because it seems to fly in the face of current policy initiatives," he said.

"People are being conned into believing in a product and paying for it through their tax monies when there's no justifiable benefit and indeed many negative costs."

Other benefits: minister
Federal Environment Minister John Baird said he knows about the report, which was commissioned under the previous Liberal government. However, he said, he is looking at the big picture.

"I think there's an issue between the tailpipe and the whole cycle," he said. "The whole cycle is better than the tailpipe."

Other ethanol proponents agreed, saying tailpipe emissions are not the only statistic that matters.

Ethanol is made from a renewable resource, they noted, and — although there is much scientific debate on this point — they argue ethanol produces fewer greenhouse gases when the entire production cycle, from gathering to refinement to emissions, is taken into account.

InfiniteNothing
04-04-2007, 10:51 PM
Ethanol is made from a renewable resource, they noted, and — although there is much scientific debate on this point — they argue ethanol produces fewer greenhouse gases when the entire production cycle, from gathering to refinement to emissions, is taken into account.
uhhh :stupid: if you don't take into account the entire cycle, you're missing a big part of the ethanol benefit.

Houdini
04-04-2007, 11:18 PM
Perhaps fewer emissions total if taken into account refining and everything else, as the last line mentioned, but it's not like that stuff goes to waste. We still get kerosene for jets, diesel, plenty of other fuels, plastics, etc., from refining oil. Not just gasoline.

And yeah, with today's modern engines, combustion is pretty thorough, and the energy in a C-C bond is basically the same whether it comes from gasoline, propane, or ethanol. So you still get CO2 with ethanol. And corn prices go up. ;)

johnnymk
04-05-2007, 04:03 AM
http://www.caranddriver.com/features/11174/tech-stuff-ethanol-promises-ethanol-and-global-warming-page4.html#save

Promise: Ethanol will save us from global warming.
When fossil fuels are burned, they release carbon that was removed from the atmosphere billions of years ago by plants and stored in fossils ever since. This release, in the form of carbon dioxide, builds up greenhouse gases that are widely believed to be causing climate change. Ethanol releases carbon dioxide, too, but some of it was removed from the air recently by the plants grown as feedstock for ethanol production. So ethanol recycles a share of its carbon, and the size of that recycled share determines its greenhouse appeal.

Ideally, ethanol would be efficient enough as a fuel to power ethanol-production factories. But it’s nowhere close. With today’s technology, the carbon dioxide released by the fossil fuel used to produce ethanol towers over the amount recycled.

Switching from gasoline to ethanol would have an “ambiguous effect” on greenhouse gases, according to the Berkeley study, with reported values ranging from a 32-percent decrease to a 20-percent increase. It concluded that a 13-percent reduction was likely per BTU.

The U.S. Department of Energy was less optimistic, concluding that E85 produces only a four-percent reduction in carbon dioxide. In the near term, ethanol has no chance of mitigating global warming.

VTGreg
04-05-2007, 07:57 AM
http://www.caranddriver.com/features/11174/tech-stuff-ethanol-promises-ethanol-and-global-warming-page4.html#save

Ethanol releases carbon dioxide, too, but some of it was removed from the air recently by the plants grown as feedstock for ethanol production. So ethanol recycles a share of its carbon, and the size of that recycled share determines its greenhouse appeal.


So if we are growing the corn specifically for ethanol there is a lower greenhouse impact, but if the corn that was originally being grown for food is being diverted to ethanol, there isn't any impact.

The only impact I can see to the net greenhouse gases released from the full life cycle of ethanol blends versus traditional gasoline is the additional gases created through the process of drilling and refining and oil.

Even if there aren't any benefits with respect to emissions, it still reduces the amount of oil being used (although the reduction is relatively small).

InfiniteNothing
04-05-2007, 09:20 AM
So if we are growing the corn specifically for ethanol there is a lower greenhouse impact, but if the corn that was originally being grown for food is being diverted to ethanol, there isn't any impact.


Why is that? As long as the plant got all it's carbon by absorbing CO2, when you burn that ethanol, you are just returning CO2 that was already in the air within the last decade. Burning ethanol is nearly carbon neutral.

I'll admit the technology has its setbacks along with biodiesel. But the technology is just starting. Inovation will push the technology onto deriving ethanol from things like switchgrass which can be grown on marginal land that wouldn't be used for anything else. Also the production will become greener and greener.

johnnymk
04-05-2007, 09:21 AM
Even if there aren't any benefits with respect to emissions, it still reduces the amount of oil being used (although the reduction is relatively small).


Nope...Ethanol has a lower BTU content compared to gasoline. Ethanol equipped vehicles get less mileage than gasoline vehicles. The more ethanol you add, the lower the fuel mileage. And we waste the oil converting it from corn to ethanol.

In other words, we still import as much or more oil.

InfiniteNothing
04-05-2007, 09:29 AM
Who cares if ethanol doesn't have the same energy density if that fuel isn't oil based? Also, again, Ethanol does not inherently need oil. With biotechnology, hopefully, it won't need any man made energy.

johnnymk
04-05-2007, 09:32 AM
Who cares if ethanol doesn't have the same energy density if that fuel isn't oil based? Also, again, Ethanol does not inherently need oil. With biotechnology, hopefully, it won't need any man made energy.

DUH??

Here's an analogy:

I am in a boat ten miles from land. There is a 1 inch hole at the bottom of the boat. I may or may not make it to shore. With some really fast rowing, I will probably make it.

But I call on my cell phone to a guy who seems pretty smart about my predicament.

He tells me for every eight rowing movements, stop and dump two buckets of water into your boat.

Seem dumb? Not only am I wasting time stopping to add water, I am making it harder to row the boat to shore.