Food vs. fuel: Scientists say growing grain for food is more energy efficient

Apr 19, 2010

Using productive farmland to grow crops for food instead of fuel is more energy efficient, Michigan State University scientists concluded, after analyzing 17 years' worth of data to help settle the food versus fuel debate.

"It's 36 percent more efficient to grow grain for food than for fuel," said Ilya Gelfand, an MSU postdoctoral researcher and lead author of the study. "The ideal is to grow corn for food, then leave half the leftover stalks and leaves on the field for soil conservation and produce cellulosic with the other half."

Other studies have looked at efficiencies for crops over shorter time periods, but this MSU study is the first to consider energy balances of an entire over many years. The results are published in the April 19 online issue of the journal & Technology.

"It comes down to what's the most efficient use of the land," said Phil Robertson, University Distinguished Professor of crop and soil sciences and one of the paper's authors. "Given finite land resources, will it be more efficient to use productive for food or fuel? One compromise would be to use productive farmland for both -- to use the grain for food and the other parts of the plant for fuel where possible. Another would be to reserve productive farmland for food and to grow biofuel grasses -- cellulosic biomass -- on less productive land."

He, Gelfand and Sieglinde Snapp, another co-author and an MSU associate professor of crop and soil sciences, analyzed data collected from 1989 to 2007 at the W.K. Kellogg Long Term Ecological Research site. That National Science Foundation-funded project studies ecology and environmental biology to provide a better understanding of both natural and managed systems. It is the only agricultural program in the 26-site NSF national LTER network.

The scientists compared the energy inputs and outputs of producing corn, soybeans and wheat grown using four systems: conventional tillage, no-till, low chemical input and organic, and then using all harvested plant material for either food or biofuel production. They also looked at energy balances for growing alfalfa, an important forage plant that can be used either for biofuel or for beef cattle feed.

The analysis showed that using no-till production to grow grain for food was the most energy-efficient system for food or fuel production. Avoiding plowing with no-till management reduces tractor fuel use during production.

Producing a kilogram of corn for human food provides more energy than converting the corn to either ethanol by processing or to meat by feeding it to animals. Growing alfalfa for biofuel is 60 percent more efficient than using it as cattle feed, according to the study.

Robertson and Gelfand also are members of the Great Lakes Bioenergy Research Center, a partnership between Michigan State and the University of Wisconsin-Madison funded by the U.S. Department of Energy to conduct basic research aimed at solving some of the most complex problems in converting natural materials to energy.

The U.S. Energy Independence and Security Act of 2007 calls for biofuels to comprise 22 percent of the nation's transportation fuels by 2022.

"This research is aimed at policymakers who have to decide how and where biofuels should be grown and the best way to encourage farmers to follow those suggestions," Robertson said.

Research by MSU agricultural economics professor Scott Swinton earlier found that the most profitable cellulosic biofuel crop right now is corn stalks and leaves.

"Our research suggests that this is an energy-efficient strategy as well, so long as the grain is used for ," Robertson said. "But there are not enough corn stalks to meet expected energy needs and federal policy also may decide to offer incentives to grow that offer more environmental benefits than , including incentives to grow grasses on less productive land.

"The promise of biofuels made from biomass is huge, from both climate mitigation and economic perspectives," he continued. "But the promise could come up short if we don't pay attention to details such as the land on which they are grown."

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jonnyboy
3.7 / 5 (6) Apr 19, 2010
This is something every 5th grader knows and the dept of Energy is paying these so-called "researchers" to produce this study?
DGBEACH
4 / 5 (4) Apr 19, 2010
This is something every 5th grader knows and the dept of Energy is paying these so-called "researchers" to produce this study?
It does seem pretty obvious now, in hindsight
Caliban
3.8 / 5 (4) Apr 19, 2010
Doubly ironic, considering that it is well established that methanol can be produced from from virtually any organic/hydrcarbon compound- yard waste, food refuse, paper, plastic, wood, garbage- you name it.

Landfills could be turned into hydrocarbon mines. Not to mention the opportunity to reclaim metals, glass, and recycle untold toxic waste. Growing food crops for biofuel is not just inefficient- it's blind.
zevkirsh
5 / 5 (5) Apr 19, 2010
this isnt hind site, there were plenty of phd educated scientists saying this before the ethanol explosion was funded by government they were ignored in favor of lobbyist, everyone knew full well this was just a go no where subsidy for big corn.
PPihkala
5 / 5 (2) Apr 19, 2010
Then there is the question of water. Do we want to use all that fresh water to make biofuels? I don't think so, if there is any signs of overuse with water.
3432682
1.7 / 5 (3) Apr 20, 2010
We needed this study to confirm the obvious. Kill the ethanol program. This wasteful program is scheduled to triple in size by 2022. That would require all the land now used to grow our corn. The subsidies cost at least $15 billion now, and cause $100 billion annually in higher food prices. Biofuels programs worldwide are sharply raising food prices, and causing hunger for hundreds of millions. The program is wasteful, expensive and causes hunger. We could be reducing our farmland requirement instead of expanding.
Skepticus
1 / 5 (1) Apr 20, 2010
Until the price of flour hits $100 a pound and humans can adapt to use air for nourishment to reserve land to produce and to fuel their vehicles, or to take over the Middle East completely,or both, this stupidity will live and prosper.
sender
5 / 5 (1) Apr 20, 2010
I bet none of the farms were using vertical farming techniques or aeroponics
jerryd
not rated yet Apr 23, 2010
Even though we produce 10x's more food than we need? Did they consider corn is a terrible human food? Look at Mexicans, early Indians who ate mostly corn and how short they are.Once they eat a better diet they grow like the rest of us.

But after making ethanol the fermentation doubled it's food value for humans or animals which it's mostly used for. So if the food value is higher after 3gal of ethanol is made/bushel, can it be that bad? You also get 1/2gal of oil plus stalks, cobs for energy/feed/biofuels.

We have plenty of crop land to make all the food we and many others need and grow fuel too. Just convert all cotton acreage to fuel with 10% as hemp for cloth instead would be 10% of our liquid fuel needs.

Personally I use wind power for my transport in my EV so don't use much fuel as it gets 250 and 600mpg in my EV sportswagon and harley size EV trike.