Cellulosic Ethanol


Feedsee Energy : Cellulosic Ethanol : Renewable fuel production that preserves food supply

Cellulosic ethanol is a type of biofuel produced from lignocellulose, a structural material that comprises much of the mass of plants. It is derived from non-food sources like agricultural and forestry waste, or energy crops like switchgrass or miscanthus.

In 2007, the Renewable Fuels Standard was adjusted to mandate production of thirty-five billion gallons of biofuel by 2017, a five-fold increase. In addition, the new Farm Bill will include two billion dollars for funding of cellulosic ethanol plants. The availability of corn starch as an ethanol feedstock is expected to limit production of ethanol to a maximum fifteen billion gallons per year, making a move to cellulosic feedstocks inevitable. To achieve thirty-five billion gallons per year of ethanol production, cellulosic ethanol will be required to fill that twenty billion gallon per year gap as a large part of an overall effort. Cellulosic ethanol addresses the issue of using food such as corn and wheat for fuel. As economist Lester Brown of the Earth Policy Institute has pointed out, ethanol plants in the U.S. were expected to consume half of the U.S. corn crop in 2008 and this had an impact on the cost and availability of foods around the world. The corn needed to fill a twenty-five gallon tank with ethanol could feed a person for a year. SunOpta's participation in existing cellulosic ethanol projects around the world confirms that large-scale commercial cellulosic ethanol production is viable.

There are several advantages of using cellulosic ethanol as a renewable biofuel:

  1. Reduced Greenhouse Gas Emissions: The use of cellulosic ethanol can significantly reduce greenhouse gas emissions compared to fossil fuels. When plants grow, they absorb CO2 from the atmosphere, effectively offsetting the emissions produced when the ethanol is burned. Studies have suggested that cellulosic ethanol could reduce greenhouse gas emissions by more than 85% over reformulated gasoline.
  2. Non-Food Feedstocks: Unlike other types of biofuels like corn ethanol, cellulosic ethanol is made from non-food crops or waste products, so its production doesn't directly compete with food production.
  3. Use of Waste Materials: Cellulosic ethanol provides a use for agricultural and forestry waste products, potentially providing additional income for farmers and foresters, and reducing problems associated with waste disposal.
  4. Lower Dependence on Foreign Oil: As with other biofuels, cellulosic ethanol can contribute to energy independence because it's produced from domestically grown crops or domestically produced waste.
  5. Potential for Sustainable Development: Perennial energy crops used for cellulosic ethanol can be grown on marginal lands that aren't suitable for conventional farming, reducing land use pressure. These crops can also improve soil quality and reduce erosion.

While cellulosic ethanol has these potential advantages, there are also challenges to its wide-scale implementation. These include the need for technological improvements to increase conversion efficiency, the costs associated with new infrastructure, and environmental concerns associated with increased cultivation of energy crops. Research and development are ongoing in these areas.