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Posts tagged: greenhouse gas emissions

Innovation is Driving Down Greenhouse Gas Emissions from Corn-based Ethanol

A flexible fuel pump with ethanol

This flexible fuel pump offers 30% and 85% ethanol fuel.

Ethanol, primarily derived from corn, supplies about 10 percent of US motor fuel needs.  A new study from ICF which was released today, titled “A Life-Cycle Analysis of the Greenhouse Gas Emissions of Corn-Based Ethanol,” finds that greenhouse gas (GHG) emissions associated with corn-based ethanol in the United States are about 43 percent lower than gasoline when measured on an energy equivalent basis.  This is comparable to reducing GHG emissions in the U.S. transportation sector by as much as 35.5 million metric tons per year.

Ethanol production has changed significantly over the past ten years. U.S. production has ramped up from 3.9 to 14.8 billion gallons per year between 2005 and 2015. As demand for corn ethanol has increased, corn production in the US expanded from 11.8 billion bushels in 2004 to 13.6 billion bushels in 2015 (NASS).

Unlike earlier studies of ethanol’s GHG benefits, which had to rely on projections of future ethanol production systems and expected impacts on the farm sector, this study was able to review how the industry and farm sectors have performed over the past decade to assess the current GHG profile of corn-based ethanol.

Earlier studies of ethanol’s GHG balance projected the effects of allocating billions of bushels of corn to ethanol production on supplies of corn and other commodities going to domestic and world food and feed markets.  Those studies expected that farmers in the U.S. and other regions would respond to higher corn prices by bringing new lands into corn production. Bringing new land into commodity production typically results in increased GHG emissions—and those emissions can be large if the former land use was native grassland, wetland, or forest. However, what actually occurred in the US and around the world is more complex.

The Three Rivers Energy biorefinery in Ohio

The Three Rivers Energy biorefinery in Ohio produces corn-based ethanol.

Increased use of corn to produce ethanol in the US did have a positive price effect on corn.  As a result, within the US and abroad, idled croplands were brought into production; cropland already in production was managed more intensively; and by-products of corn ethanol production were used more efficiently as animal feed. Around the world, producers increased their use of double cropping.

The ICF report draws on those new data, including the analysis in Bruce Babcock and Zabid Iqbal’s publication “Using Recent Land Use Changes to Validate Land Use Change Models”.  Babcock and Iqbal’s study confirmed that the primary land-use change response by the world’s farmers to increased demand for corn during the period 2004-2012 was to increase double cropping, reduce un-harvested planted area, reduce fallow land, and reduce temporary pasture in order to expand production. Moreover, the use of distillers dried grains and solubles (or DDGS) became a preferred substitute for corn grain, thereby muting the increased demand.

Those types of production gains are emblematic of innovation in modern agriculture. In 1961, it took 3.38 billion acres of cropland to feed the world’s population of 3.5 billion people. Over the next fifty years, the world’s population doubled to seven billion people, while cultivated land increased by only 12 percent to 3.78 billion acres. Productivity gains driven by improvements in technology have allowed farmers to get more output from existing resources, and thereby to keep pace with the growing demands an increasing global population puts on agriculture for food, fiber, and energy products.

In addition to the gains from reduced levels of land conversion, the ICF report shows that the reductions in GHG emissions from corn ethanol are continually driven by a variety of improvements in efficiency, from the corn field to the ethanol refinery. On-farm conservation practices, such as reduced tillage and nitrogen management, improved the GHG balance of growing corn for ethanol. Production yields, measured in gallons of ethanol per bushel of corn, have increased by 3.4 percent between 2006 and 2014.

Ethanol plants have also improved process efficiencies and can now produce biofuels that generate double the lifecycle GHG reductions estimated earlier, and there are opportunities to improve performance even more. New enzymes and yeast strains have increased process efficiencies in starch conversion and fermentation. Those process upgrades have become drivers for a decreasing GHG-intensity of corn ethanol production. Improved technologies such as combined heat and power, and using landfill gas for energy offer continued areas for improved efficiencies.  New co-products, such as corn-oil biodiesel and DDGS have helped reduce GHG lifecycle emissions.

The report concludes that the GHG profile of corn ethanol is on track to be almost 50 percent lower than gasoline in 2022 if current trends in corn yields, process fuel switching, and improvements in trucking fuel efficiency continue.

One of the ICF report’s important findings is that there is a large potential for additional gains in ethanol’s GHG efficiency. The study examined the potential GHG benefits of additional on-farm conservation practices and efficiency improvements, such as the practices outlined in USDA’s Building Blocks for Climate Smart Agriculture and Forestry strategy. When these practices and plant efficiency improvements are universally adopted, the GHG benefits of corn ethanol are even more pronounced over gasoline—potentially rising to 76 percent gain in GHG benefits.

Continuing these trends is good news for the transportation sector—and the agriculture sector—when it comes to reducing GHG emissions.

A nearly 100 percent biodegradable kitty litter made from dried distiller’s grains, left over from corn-ethanol production

USDA scientists have developed a nearly 100 percent biodegradable kitty litter made from dried distiller’s grains, left over from corn-ethanol production.

Climate Smart Conservation Partnership Serves Two Scoops of On-Farm Solutions

Ben & Jerry’s and their dairy partners

Ben & Jerry’s and its dairy partners will use the information generated by COMET to identify on-farm conservation actions—such as approaches to manure management and soil health management practices—that can help reduce greenhouse gas emissions and sequester carbon. Photo: Kari Cohen, NRCS.

Eating a pint of Ben & Jerry’s ice cream may make you feel guilty about your waistline, but thanks to a new partnership between the ice cream company and USDA’s Natural Resources Conservation Service (NRCS), you may be able to feel less guilty about contributing to climate change. The partnership is designed to help Ben & Jerry’s milk suppliers—generally small dairies—understand their greenhouse gas footprint and consider voluntary conservation approaches to reduce that footprint.

NRCS and Ben & Jerry’s will help dairies implement conservation practices that meet Ben & Jerry’s objective of “Happy Cows, Happy Planet, & Happy Farmers.” Through its Caring Dairy sustainability program, Ben & Jerry’s will use USDA’s suite of greenhouse gas estimation tools, COMET-FarmTM and COMET-PlannerTM, to quantify on-farm GHG emissions and reductions. The COMET tools—COMET stands for CarbOn Management & Emissions Tool – are a product of a long-standing partnership between NRCS and Colorado State University. Read more »

Unique Conservation Partnership Helps Create Win-Win Situation

Raven's Nest Nature Preserve

Raven’s Nest is one of two ranches that will protect more than 15,000 acres of grassland in southeastern Colorado. Photo by Michael Menefee.

By keeping their grasslands intact, two Colorado ranches are reducing greenhouse gas emissions and protecting vital wildlife habitat, all while earning additional revenue.

It may seem too good to be true, but it is thanks to a unique partnership spearheaded by the Climate Action Reserve, one of North America’s leading carbon offset project registries.

With the help of a Conservation Innovation Grant (CIG) from USDA’s Natural Resources Conservation Service (NRCS), the Climate Action Reserve listed Raven’s Nest and Heartland Ranch, both owned by the Southern Plains Land Trust (SPLT), as the first two grassland offset projects developed and executed under a new Grassland Project Protocol. Read more »

Addressing Climate Change Today for a Healthier Tomorrow

Ned Wood looking out at land

Photo: Ned Wood began a life long dream of ranching and he now leads a thriving family business that has endured and will improve the lives of hundreds of his cows, calves and yearlings that graze the approximately 4,000 acres of drought stricken range land in the 6,255 acre East Bay Regional Park District’s Briones Regional Park in Contra Costa County, CA. Image: USDA Results Badge.

USDA is bringing tools and solutions to farmers, foresters and ranchers so they have help confronting climate change while working to produce a global food supply adequate to feed the 9 billion people estimated by 2040 while still protecting the earth’s natural resources.

Today, USDA is launching the fifth chapter of USDA Results, telling the story of how USDA has been working since 2009 with partners across the country and around the world to curb the effects of climate change for a healthier tomorrow. Throughout May, we will be announcing new projects and highlight the progress we’ve made under Secretary Vilsack’s leadership, which has made this issue one of his top priorities. Here in the Climate Change Program Office and in Agencies across the Department, we have been busy. Read more »

USDA Conservation Innovation Grant Helps Rice Growers Reduce Greenhouse Gas Emissions and Voluntarily Participate in California’s Carbon Market

Poly pipe and alternate wetting and drying

Arkansas Rice Growers implement precise water management to reduce greenhouse gas emissions by utilizing poly pipe and alternate wetting and drying. Photo credit: Adam Chambers.

Imagine a rice farmer in Arkansas altering his water management techniques to deliver water more efficiently and use fewer days of flooding, allowing for more precise water and nutrient management while maintaining consistent yields. After a decision by the California Air Resources Board (CARB), in addition to improving water quality and reducing water use and nutrient input costs, that Arkansas farmer now has the option of selling carbon credits to large regulated emitters in California.   

In 2012, California put in place a cap-and-trade program for greenhouse gas emissions, one of the most aggressive climate change programs in the world. Last week’s groundbreaking vote by CARB adopted the first crop-based agricultural offset protocol, designed to reduce methane and nitrous oxide emissions from rice production. Methane and nitrous oxide are potent greenhouse gases emitted through the cultivation and fertilization of rice fields. Read more »

Study Finds Increasing Wood Pellet Demand Boosts Forest Growth, Reduces Greenhouse Gas Emissions, Creates Jobs

A truck is filled with wood chips.

A truck is filled with wood chips as part of the process of turning wood into energy.

An industry that can reduce greenhouse gas emissions, increase forest growth, and create jobs sounds too good to be true.  But that is the reality of the emerging wood pellets market in the Southern U.S.  That conclusion is supported by independent economic assessments of wood bioenergy, including a recent study that specifically focused on European pellet demand conducted by researchers at Duke and North Carolina State Universities.  Those researchers found that increasing demand for wood pellets resulted in more forest area, more forest investment, large greenhouse gas reductions, and little change in forest carbon inventories.

So, why is there concern?

Some critics have recently argued that land used to produce biomass for energy should instead be permanently protected as forests. They say that harvesting biomass from forests reduces forest carbon stocks. Instead, they claim that the best way to increase carbon storage is to reduce demand for renewable products that come from the land. Read more »