Sustainable Energy

As concern over global climate change increases and our supplies of fossil fuels dwindles, MAFES scientists turn to alternative sources of energy. One of the most promising technologies for a fossil fuel replacement: biomass-to-liquid fuels, or BTL. The technology uses biomass, such as woodchips or switchgrass, to generate liquid fuel that acts as an alternative to fossil fuels. Because woodchips and switchgrass are plant-based, they are quickly renewable—unlike fossil fuels, which require millions of years to form. One of the main breakthroughs of the project was developing a one-step conversion process that transforms the biomass into syngas—a fuel gas mixture that consists of hydrogen, carbon monoxide, and carbon dioxide—which then can be converted into a number of different fuel types. Read More

Agronomist Normie Buehring has been testing his green thumb on sunflowers, a crop that has potential as a food and bioenergy crop that farmers can grow in Mississippi. At the North Mississippi Research and Extension Center in Verona, scientists set out to evaluate new hybrid sunflowers with shorter stems, about 3–4 feet tall. They later planted the sunflowers at four locations around Mississippi as far north as Verona and as far south as Newton. Yield and oil content were equivalent to sunflowers grown in the North, where the flowers are typically raised. However, the Mississippi-grown sunflower seeds contained higher concentrations of oleic acid than the original planting seed. The high oleic acid content would be good for high-quality cooking oil production. Seed production and oil content are also important for bioenergy production.

The emergence of biomass-based energy warrants the evaluation of synthetic gas, or "syngas," as a fuel for personal power systems. Syngas uses oxygen to convert biomass and coal into carbon monoxide and hydrogen. MAFES scientists recently examined the performance and exhaust of a commercial generator modified to run on 100 percent syngas compared with a gasoline-powered generator. The overall efficiency of the generator at maximum electrical power output was the same for both fuels.

MAFES researchers are examining the U.S. demand for ethanol. They conducted a nationwide contingent- valuation survey of consumer fuel blends E-10 (a blend of 10 percent ethanol and 90 percent gasoline) and E-85 (a blend of 85 percent ethanol and 15 percent gasoline) to estimate willingness to pay for these products and to identify key characteristics driving demand. Results indicate that overall perceptions of ethanol are positive, but ethanol is not the globally-preferred transportation energy alternative.

Scientists have identified a species of grassy feedstock that works well in sustainable bioenergy production. Giant miscanthus, a warm-season Asian grass, has potential as a biomass crop for fuel. MAFES scientists have isolated, identified and selected a genotype of the species that fits agricultural production systems of Southeastern farmers. This perennial plant offers several production advantages. It produces biomass that can grow as tall as 12 feet and thrives on marginal cropland. The crop is tolerant of drought and excessive rain, and it requires few inputs once established and maintained under a one-cut system. Giant miscanthus can be harvested and baled like hay using the same type of equipment.

Biochemist Ashli Brown gained national attention for a unique approach to natural biofuel production: the use of “panda poop.” More specifically, she discovered that microbes in panda feces are strong enough to efficiently break down woody material and other tough plants. These bacteria could tremendously cut production costs for alternative fuels and allow the use of plants other than food crops. One of the most expensive processes in making biofuels is the pretreatment, where sugar polymers in plants are chemically treated so they can be fermented and distilled to make ethanol. Enzymes in the bacteria speed up the break down of cellulose into simple sugars and thus offer a more energy-efficient way to turn materials such as switchgrass, corn stalks, and wood chips into biofuel. Brown and fellow biochemist Darrell Sparks conducted a 14-month study of the giant pandas at the Memphis Zoo. While the initial focus of the study was to observe the overall health and nutrition of the pandas, they found several species of bacteria that break down cellulitic plant material that is generally difficult to digest. These microbes are similar to bacteria that help termites digest wood, but the panda-associated bacteria appear to be more efficient at breaking down plant materials and may work in a way that is better for biofuel manufacturing. So far, the scientists have identified 40 high-potential bacteria species in the pandas’ digestive tracts. Read More

MAFES scientists are looking to "panda poop," or microbes in panda excrement that breakdown woody materials, as a possible means to biofuel production. Scientists recently discovered that microbes in panda feces are strong enough to break down the toughest plant materials. Panda poop might help overcome one of the major challenges to producing biofuels: breaking down the raw plant materials used to make the fuels. The findings have garnered national attention as the reproduction of these microbes could contribute to developing alternative fuels that don’t interfere with food crops and could also save a great deal of money. One of the most expensive processes in making biofuels is the pretreatment, where sugar polymers are chemically treated so that they can be used to make ethanol or oil. If you can insert a microbe that does that naturally and efficiently, production costs for alternative fuels would be cut tremendously. Read More

Poultry is big business in Mississippi. In 2016, the state’s broiler production value totaled $2.23 billion dollars. A researcher in the Mississippi Agricultural and Forestry Experiment Station and an engineering specialist in the MSU Extension Service are studying ways to optimize energy efficiency in poultry houses to reduce producer inputs and increase their bottom lines. Energy expenditures account for about 60 percent of the input costs for the state’s nearly 1,500 poultry producers. Heating fuel alone can hover in the 40 percent range. MAFES scientists studied energy transfer in poultry houses while extension specialists studied heaters and lighting. Each focused on ways to reduce producer inputs and increase efficiencies of the housing envelope across the life of a facility. Read More

The uses of perennial warm-season grasses are as varied as the plants themselves. Applications include poultry bedding, cattle forage, conservation plantings, bioenergy, and much more. Scientists in the Mississippi Agricultural and Forestry Experiment Station have been propagating grasses as bioenergy crops since the early 2000s. Now as demand for renewable energy crops shift, MSU’s perennial grass research evolves to meet other needs. Read More

Energy beets could provide an off-season crop for Mississippi farmers and an alternative energy source for the nation’s expanding biofuel industry. At the Delta Research and Extension Center in Stoneville, plant scientist Wayne Ebelhar and other researchers are examining the growth and profit potential for varieties of energy beet, a nonedible relative of the sugar beet used only in biofuel production. Because they are traditionally grown in much cooler climates, energy beets will grow best during Mississippi winters as a cover crop on fields between fall harvest and spring planting. MSU Extension agents are enlisting farmers willing to grow energy beets to test how well the crop grows in Mississippi and whether it can be produced at a profit. While energy beets are not a cheap crop to grow—about $700 per acre—the financial breakeven point would be yields around 20 tons per acre. Energy beets could yield as much as 50 tons per acre. After a few more years of testing, scientists are confident energy beets will make an excellent winter crop with minimal insect, disease, and weed pressure during the cold months. Read More

The castor plant thrives in Mississippi and produces great quantities of valuable oil in its seeds, but castor seed meal contains the toxic protein ricin and is dangerous to handle in commercial production. Doctoral student Daniel Barnes is working on a method of removing this danger. Castor oil can be used to produce cosmetics, paints, plastics, biodiesel, jet aircraft lubricants, and components for various industrial chemical processes. Mississippi’s climate would promote castor seed yields in excess of 1 ton per acre, an amount that could produce an impressive 1,000 pounds of oil. To make castor a commercially viable U.S. crop, Barnes is trying to genetically modify the plant so that its ricin-related gene is either no longer expressed or no longer produces the toxin. He has successfully transformed castor cells but has so far been unable to grow whole plants from the cells. Genetic modification involves inserting a fragment of foreign DNA into the plant of interest. One problem is that castor is a one-of-a-kind plant with no close relatives. Barnes is searching for possibly useful genetic code in castor’s closest biological relatives, including poinsettia, spurge, and rubber trees. Read More

Plant scientist Brian Baldwin spent years developing a variety of giant miscanthus for use in biofuel production. Baldwin’s discovery, an adaptation of a perennial grass native to Asia, is particularly suited to the Southeast’s climate and soils, and it produces more biomass per acre than other bioenergy crops. MSU filed a plant patent application for the resulting variety, named Freedom, in 2010 and licensed it to Georgia-based Repreve Renewables LLC. Cool Planet Biofuels has used Freedom giant miscanthus to create gasoline, a breakthrough in the biofuels industry. In a pilot test, Cool Planet generated about 4,000 gallons of gasoline per acre of biomass using Freedom grown under nearly optimal crop growth conditions. Their process used air-dried, coarsely ground grass subjected to moderately high temperature and pressure to produce a ready-to-use gasoline, chemically identical to the petroleum-based fossil fuel. Baldwin also works to develop other crops suitable for biomass production, including oilseed crops, native and exotic grasses, and Sunn hemp, kenaf, and other fiber crops. For example, he is testing several switchgrass species for their ability to germinate on demand, which would allow farmers to increase yields of this biomass crop. Baldwin also examines the use of traditional crops as alternative energy sources. In one such project, he works to improve the sugar content of a sweet sorghum variety. In collaboration with the USDA-ARS, Baldwin is developing a cold-hardy sugarcane variety.