Wednesday, May 05, 2010
Ethanol: A New Study Indicates Its Environmental Score Is Better
In the past year, the future of ethanol as a market for Midwestern corn has been substantially challenged by the California Air Resources Board (CARB), which has alleged that producing ethanol from US corn forces more land to be cleared in the Amazon jungles to produce food for the world. The theory is referred to as “indirect land use” and quantifying the impact has been a controversial effort. Purdue economist Wally Tyner early on pointed to the negative impact, but has modified his position.Tyner’s credibility with analyzing ethanol economics secured him an invitation to be on the CARB, where there are as many ethanol opponents as there are supporters. His recent revisions to his calculations reduced about 10% of the total emissions expected from an increase in corn production that was destined for ethanol refineries. And he says the new data “better reflects market conditions and land productivity than a 2009 report that showed corn ethanol wouldn't significantly lower greenhouse gas emissions over gasoline.” Essentially the change decreases the acreage needed to produce 1,000 gallons of ethanol, and fewer acres would be needed in Brazil, which had been the concern of the California policy makers opposed to ethanol.
Tyner’s research indicates that some argue it is impossible to measure land use changes resulting from ethanol production and others argue that failure to do so will result in incorrect policy conclusions. Saying his findings are between those positions, Tyner says the land needed to meet US ethanol mandates ranges from 0.29 to 0.54 acres per 1,000 gallons of ethanol produced, which he characterizes as a wide range.
Tyner says land use for ethanol production is determined by using a conversion factor of 2.7 gallons per bushel, and 370 bushels per hectare or 2.47 acres to arrive at 1000 gallons of ethanol per hectare. Since the federal mandate calls for 15 billion gallons of ethanol by 2015, that would require 13 million hectares or 32 million acres of additional land beyond his 2001 starting point.
Based on the global economy and US ethanol production trends from 2001 to 2006, Tyner says since 2006 ethanol production needed to meet the federal mandates would require 7.3 million additional acres of land, 34% of which would be in the US and 66% would be in other nations. That would require the maximum of amount of land for ethanol production, but that is 16.7% smaller than what had been calculated a year ago, and created substantial concerns from ethanol opponents.
As most Cornbelt farmers know, as planted acreage expands, the last acre to be planted is much less productive than the first, and Tyner says the marginal land added late in the process would have yields that are incrementally lower. Among the factors that entered into the process were:
1) Population and how it changed prior to 2006
2) GDP and its percentage of change for each region of the world
3) Capital and how much was formed for each region
4) Labor statistics based on skilled and unskilled
5) Crop production data by crop and country
6) Harvested acreage
7) Crop yields and the cumulative yield change
8) Global Export prices for forest products
9) Changes in forested lands
Based on the changes from 2001 to 2006, Tyner’s more recent data indicates a nearly 35% reduction in the amount of acreage needed to produce the mandated amount of ethanol. That is because less land is needed to produce 1,000 gallons of ethanol due to increasing crop yields.
Another focus of the report is the amount of carbon dioxide released into the atmosphere with corn production and ethanol refining, and particularly with the loss of forest which is no longer storing carbon. Tyner says it is possible to attach a carbon loss number to each gallon of ethanol produced, and like crop yield, the first gallon of ethanol produced releases less carbon dioxide than the last gallon produced. Compared to his earlier analysis, Tyner says the amount of carbon dioxide release has declined more than 16% per gallon of ethanol, and may be as much as 21%.
Summary:
New data, a new way to analyze the data, and ethanol looks better as a renewable fuel than it did a couple years ago when California critics blamed it for consuming too much foreign farmland. Based on better corn yields than expected for one, ethanol will not require as much land to meet federal mandates and its release of carbon dioxide will not be as bad as originally thought.
Posted by Stu Ellis on 05/05 at 01:11 AM | Permalink