Featured Research

from universities, journals, and other organizations

Researchers Identify Energy Gains And Environmental Impacts Of Corn Ethanol And Soybean Biodiesel

Date:
July 12, 2006
Source:
University of Minnesota
Summary:
The first comprehensive analysis of the full life cycles of soybean biodiesel and corn grain ethanol shows that biodiesel has much less of an impact on the environment and a much higher net energy benefit than corn ethanol, but that neither can do much to meet U.S. energy demand. The study was conducted by researchers in the University of Minnesota's College of Biological Sciences and College of Food, Agricultural and Natural Resource Sciences.

The first comprehensive analysis of the full life cycles of soybean biodiesel and corn grain ethanol shows that biodiesel has much less of an impact on the environment and a much higher net energy benefit than corn ethanol, but that neither can do much to meet U.S. energy demand.

The study, which was funded in part by the University of Minnesota’s Initiative for Renewable Energy and the Environment, was conducted by researchers in the university’s College of Biological Sciences and College of Food, Agricultural and Natural Resource Sciences. The study will be published in the July 11 Proceedings of the National Academy of Sciences.

The researchers tracked all the energy used for growing corn and soybeans and converting the crops into biofuels. They also looked at how much fertilizer and pesticide corn and soybeans required and how much greenhouse gases and nitrogen, phosphorus, and pesticide pollutants each released into the environment.

“Quantifying the benefits and costs of biofuels throughout their life cycles allows us not only to make sound choices today but also to identify better biofuels for the future,” said Jason Hill, a postdoctoral researcher in the department of ecology, evolution, and behavior and the department of applied economics and lead author of the study.

The study showed that both corn grain ethanol and soybean biodiesel produce more energy than is needed to grow the crops and convert them into biofuels. This finding refutes other studies claiming that these biofuels require more energy to produce than they provide. The amount of energy each returns differs greatly, however. Soybean biodiesel returns 93 percent more energy than is used to produce it, while corn grain ethanol currently provides only 25 percent more energy.

Still, the researchers caution that neither biofuel can come close to meeting the growing demand for alternatives to petroleum. Dedicating all current U.S. corn and soybean production to biofuels would meet only 12 percent of gasoline demand and 6 percent of diesel demand. Meanwhile, global population growth and increasingly affluent societies will increase demand for corn and soybeans for food.

The authors showed that the environmental impacts of the two biofuels also differ. Soybean biodiesel produces 41 percent less greenhouse gas emissions than diesel fuel whereas corn grain ethanol produces 12 percent less greenhouse gas emissions than gasoline. Soybeans have another environmental advantage over corn because they require much less nitrogen fertilizer and pesticides, which get into groundwater, streams, rivers and oceans. These agricultural chemicals pollute drinking water, and nitrogen decreases biodiversity in global ecosystems. Nitrogen fertilizer, mainly from corn, causes the 'dead zone' in the Gulf of Mexico.

“We did this study to learn from ethanol and biodiesel,” says David Tilman, Regents Professor of Ecology and a co-author of the study. “Producing biofuel for transportation is a fledgling industry. Corn ethanol and soybean biodiesel are successful first generation biofuels. The next step is a biofuel crop that requires low chemical and energy inputs and can give us much greater energy and environmental returns. Prairie grasses have great potential.”

Biofuels such as switchgrass, mixed prairie grasses and woody plants produced on marginally productive agricultural land or biofuels produced from agricultural or forestry waste have the potential to provide much larger biofuel supplies with greater environmental benefits than corn ethanol and soybean biodiesel.

According to Douglas Tiffany, research fellow, department of applied economics and another co-author of the study, ethanol and biodiesel plants are early biorefineries that in the future will be capable of using different kinds of biomass and conversion technologies to produce a variety of biofuels and other products, depending upon market demands.

Hill adds that both ethanol and biodiesel have a long-term value as additives because they oxygenate fossil fuels, which allows them to burn cleaner. Biodiesel also protects engine parts when blended with diesel.

“There is plenty of demand for ethanol as an additive,” Hill says. “The ethanol industry was built on using ethanol as an additive rather than a fuel. Using it as a biofuel such as E85 is a recent and currently unsustainable development. As is, there is barely enough corn grown to meet demand for ethanol as a 10 percent additive.”


Story Source:

The above story is based on materials provided by University of Minnesota. Note: Materials may be edited for content and length.


Cite This Page:

University of Minnesota. "Researchers Identify Energy Gains And Environmental Impacts Of Corn Ethanol And Soybean Biodiesel." ScienceDaily. ScienceDaily, 12 July 2006. <www.sciencedaily.com/releases/2006/07/060710180310.htm>.
University of Minnesota. (2006, July 12). Researchers Identify Energy Gains And Environmental Impacts Of Corn Ethanol And Soybean Biodiesel. ScienceDaily. Retrieved April 24, 2014 from www.sciencedaily.com/releases/2006/07/060710180310.htm
University of Minnesota. "Researchers Identify Energy Gains And Environmental Impacts Of Corn Ethanol And Soybean Biodiesel." ScienceDaily. www.sciencedaily.com/releases/2006/07/060710180310.htm (accessed April 24, 2014).

Share This



More Matter & Energy News

Thursday, April 24, 2014

Featured Research

from universities, journals, and other organizations


Featured Videos

from AP, Reuters, AFP, and other news services

Next Stop America for France's TGV?

Next Stop America for France's TGV?

Reuters - Business Video Online (Apr. 24, 2014) General Electric keeps quiet on reports it's in talks to buy French turbine and train maker Alstom. Ivor Bennett reports on what could be an embarrassing rumour for the French government, with business-friendly reforms proving a hard sell. Video provided by Reuters
Powered by NewsLook.com
Raw: Obama Plays Soccer With Japanese Robot

Raw: Obama Plays Soccer With Japanese Robot

AP (Apr. 24, 2014) President Obama briefly played soccer with a robot during his visit to Japan on Thursday. The President has been emphasizing technology along with security concerns during his visit. (April 24) Video provided by AP
Powered by NewsLook.com
Obama Encourages Japanese Student-Scientists

Obama Encourages Japanese Student-Scientists

AP (Apr. 24, 2014) President Obama spoke with student innovators in Japan and urged them to take part in increased opportunities for student exchanges with the US. (April 24) Video provided by AP
Powered by NewsLook.com
UN Joint Mission Starts Removing Landmines in Cyprus

UN Joint Mission Starts Removing Landmines in Cyprus

AFP (Apr. 23, 2014) The UN mission in Cyprus (UNFICYP) led a mine clearance demonstration on Wednesday in the UN-controlled buffer zone where demining operations are being conducted near the Cypriot village of Mammari. Duration: 01:00 Video provided by AFP
Powered by NewsLook.com

Search ScienceDaily

Number of stories in archives: 140,361

Find with keyword(s):
Enter a keyword or phrase to search ScienceDaily for related topics and research stories.

Save/Print:
Share:

Breaking News:
from the past week

In Other News

... from NewsDaily.com

Science News

Health News

Environment News

Technology News



Save/Print:
Share:

Free Subscriptions


Get the latest science news with ScienceDaily's free email newsletters, updated daily and weekly. Or view hourly updated newsfeeds in your RSS reader:

Get Social & Mobile


Keep up to date with the latest news from ScienceDaily via social networks and mobile apps:

Have Feedback?


Tell us what you think of ScienceDaily -- we welcome both positive and negative comments. Have any problems using the site? Questions?
Mobile: iPhone Android Web
Follow: Facebook Twitter Google+
Subscribe: RSS Feeds Email Newsletters
Latest Headlines Health & Medicine Mind & Brain Space & Time Matter & Energy Computers & Math Plants & Animals Earth & Climate Fossils & Ruins