Farming for fuel
The world needs to use energy smartly and generate it from renewable sources.
COMPANIES the world over are in pursuit of alternatives to fossil fuels. DuPont, too, is in the race.
Armed with the belief that biology will help reduce the global reliance on fossil fuels, the company is deriving two biofuels from renewable materials, cellulosic ethanol and biobutanol, aside from developing various technologies to boost the photovoltaic sector.
Cellulosic ethanol or ethanol from nonfood sources, can potentially reduce greenhouse gas emissions from 80% to 150% when compared with petrol. The DuPont Danisco Cellulosic Ethanol pilot plant in Vonore, Tennessee, is set to deliver cellulosic fuels to the market by 2012.
The ethanol will be processed from agriculture waste such as corn cob, stalk and husk, as well as switchgrass, according to Jan Koninekx, DuPont business director for biofuels.
“We want to use feedstock that is already available, so agriculture residue is a good place to start. This is also easier to process than wood. But as we are going large-scale, we also need other feedstock and that is why we are also processing switchgrass.”
He says switchgrass (an energy crop that is produced solely for conversion to fuel) is native to the United States and suitable for planting on marginal land, so there is no fear of competition with other food crops for farmland. The hardy crop not only tolerates poor soils, flooding and drought, but is also resistant to pests and diseases, making it a choice raw material for producing biofuel.
To ensure a constant supply of switchgrass for the ethanol plant, there is a tie-up with the company Genera Energy.
“6,000acres (2,400ha) are being planted with switchgrass under contract with 60 farmers around Vonore. We are also developing a system to harvest, transport, store and process the biomass,” says Kelly Tiller, president of Genera Energy.
To develop biobutanol, which is considered as the next generaton of biofuels, DuPont has teamed up with oil company BP. Biobutanol holds much promise as it is superior to other biofuels and has properties similar to petrol. For example, it has higher energy density, so it will give more kilometres per litre. Petrol blended with butanol is less susceptible to separation in the presence of water than ethanol/petroleum blends. As a result, it can easily be used in the industry’s existing distribution infrastructure without requiring modifications.
DuPont’s Butamax Advanced Biofuels buthanol demonstration facility that is under construction in Hull, Britain, will process corn grain, wheat grain and sugarcane to derive biobutanol. The fuel is expected to be commercially available in 2013.
DuPont is also a major technology supplier to the photovoltaic industry, producing components used in both crystalline silicon DuPont and Bio Architecture Labs are studying if sugars from seaweed can be turned into isobutanol fuel. and thin-film solar cells and modules. The components, which include resins, encapsulation sheets, flexible substrates, conductive pastes and seals, are designed to work together to protect the sensitive portions of solar modules and increase their efficiency and lifetime. One new component under development is a material to replace the glass used in thin-film solar cells.
“As thin film solar cell is susceptible to moisture, it has to be sandwiched between sheets of glass. This takes away its flexibility and adds to its weight. The DuPont material, made from standard polymer and a proprietary Du Pont material, will work in the same manner to block water vapour from the PV cell, yet is flexible, transparent and light,” explains Steve Freilich, DuPont director of DuPont’s Solamet screen-printable thick film enables solar cell manufacturers to reduce cost per watt by achieving higher cell efficiencies and production yields and lower material consumption. material science.
The US Department of Energy is funding the research into the new material, which is suitable for all thin-film solar modules. The company is also working with the federal government and university partners to develop solar cells for military and commercial applications that are targeting a 50% solar module efficiency rate verses the 15% efficiency of conventional technology.