POET cellulosic ethanol cuts greenhouse gas emissions by 111 percent over gasoline

Ethanol produced by Project LIBERTY, POET's first planned commercial cellulosic ethanol plant, will reduce carbon emissions by 111 percent over gasoline, an independent lifecycle analysis shows.

This means POET’s cellulosic ethanol actually has negative emissions; it will offset more greenhouse gas emissions than it produces.

“Not only is cellulosic ethanol a clean and safe alternative fuel, in cases such as Project LIBERTY, it can literally reverse some of the effects of our nation’s dependence on fossil energy such as oil,” POET CEO Jeff Broin said. “By expanding the number of sources for ethanol production, the entire nation can contribute to helping our nation’s economy, security and environment through alternative fuel production.”

Broin presented the results to reporters today at the Fuel Ethanol Workshop & Expo in St. Louis, Mo. A lifecycle analysis tracks the emissions of ethanol production from “field to tank.” It includes emissions from planting and harvest, feedstock transportation, conversion to ethanol, waste products, co-products and transportation of the ethanol. It also includes Environmental Protection Agency calculations for changes in land use and effects on agriculture inputs.

The analysis, compiled by Air Improvement Resource, Inc. out of Novi, Mich., highlights a number of characteristics of POET’s process that lead to this large emissions reduction.

- Project LIBERTY produces ethanol from agriculture waste. Because it uses a waste product from an existing crop, there are no additional inputs for planting and growing the feedstock.

- The disputed theory of Indirect Land Use Change, which creates an emissions penalty for grain-based ethanol, does not have any penalty associated with POET’s cellulosic ethanol.

- The waste stream from POET’s process is fed into two anaerobic digesters to create biogas. Enough biogas is produced to completely power both Project LIBERTY and the adjacent grain-based ethanol plant. The natural gas that is displaced in this process is credited to the cellulosic ethanol plant.

“The production of biogas as a co-product is an exciting aspect of this process,” Broin said. “We will use renewable energy to produce renewable energy.”

The analysis found that all the inputs into Project LIBERTY will emit 41.8 grams of carbon dioxide equivalent units per megajoule of energy produced. The biogas exported as a co-product will offset 49.8 gCO2eq/MJ. EPA estimates for land use and agriculture changes offset an additional 1.7 gCO2eq/MJ, bringing Project LIBERTY’s total emissions to -9.7 gCO2eq/MJ.

EPA’s standard for gasoline emissions is 92.9 gCO2eq/MJ.

The Project LIBERTY lifecycle analysis was conducted using the most current design elements available. However, POET will continue to learn from laboratory work and its pilot cellulosic ethanol plant currently operating in Scotland, S.D. As changes occur, the analysis will be updated.

source: renewableenergyworld