February 27, 2008

Iowa State Releases Another Land Use Study

Last week, economists at Iowa State University released another land use study. In it they make a case that because standard life cycle analysis don't take some factors such as land use changes into account, that a new method for measuring greenhouse gas emissions is needed for biofuels. And they suggest a method called system wide analysis.

Life cycle analysis (LCA) is the standard approach used to evaluate the greenhouse gas (GHG) benefits of biofuels. However, it is increasingly recognized that LCA results do not account for some impacts—including land use changes—that have important implications on GHGs. Thus, an alternative accounting system that goes beyond LCA is needed. In this paper, we contribute to the literature by laying out the basics of a system-wide accounting (SWA) method that takes into account all potential changes in GHGs resulting from biofuel expansion. We applied both LCA and SWA to assess the GHG impacts of ethanol based on Iowa corn.

The part that strikes me as odd about all this is that they are continuing to compare biofuels to the past methods of producing gasoline. For example...

For many products, including fossil fuels, a standard LCA is generally
all that is needed to understand GHG emission implications.

In other words they are suggesting that the production of gasoline doesn't cause any land use impacts. While that may be true for offshore drilling or drilling in the desert, it doesn't apply to projects such as the oil sands of Canada.

The oil sands of Canada are found underneath an area over 54,000 square miles in size. The deposits are recovered by one of two methods. Deposits that lie close to the surface are recovered through strip mining, deposits that lie deeper underground are recovered in situ, meaning in place.

The area that is to be strip mined is about 1300 square miles in size. And since that requires that the existing swampland be drained and forest be cleared, that means there are some really big land use impacts to be considered.

The area that will be subject to in situ recover techniques will also have land use issues as roads will have to be cut and pipelines laid in.

So there are land use issues that need to be considered for oil as well.

The oil sands also require much more energy to recover than conventional deposits of oil. That means that the energy balance of oil sands is lower. In fact it is estimated that it takes the amount of energy in a barrel of oil to recover 3 barrels of oil in this manner. And the amounts of greenhouse gases associated with recovery are also about 3 times higher.

Refining is also harder and greenhouse gas emissions associated with refining oil sands oil is estimated to be 15% to 40% higher than oil from conventional sources.

So not only does the oil sands projects cause land use changes that needs to be accounted for but it also produces larger amounts of greenhouse gases at the refineries.

As the easier sources of conventional crude oil are used up more and more production will be shifting to these types of projects. In addition to the Canadian oil sands projects, oil sands in Venezuela are already starting to be produced as well.

And as it is, Canada is our largest supplier of oil and about 47% of the oil produced in Canada in 2006 came from oil sands.

The point I am trying to make is that the researchers shouldn't be performing system wide analysis (SWA) on ethanol and comparing that to gasoline's life cycle analysis (LCA). They should be scrutinizing both ethanol and gasoline with the same analysis method.


Greenhouse Gas Impacts of Ethanol from Iowa Corn: Life Cycle Analysis versus System-wide Accounting
Alberta Energy: Oil Sands
Alberta Energy: What is Oil Sands
EIS: Tar Sands
Wikipedia: Tar Sands
The Harm the Tar Sands Will Do
Refinery pollution may soar

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