Natural Gas vs. Energy Innovation
by Kate Bechen (Ethanol Producer Magazine) The production of ethanol is a complex, energy intensive process. Critics often cite the energy usage of ethanol plants and the wastes produced by the production of ethanol, especially corn-based ethanol, as lessening the benefits of ethanol production. But many ethanol plants are challenging these criticisms head on by leveraging efficiencies to reduce water use, utilizing renewable energy sources in production or recovering waste heat.
…About 90 percent of total energy consumed in the production process is thermal. The steam is needed for the starch conversion process, distillation and evaporation. Typically, the thermal energy is produced from fossil fuels (mostly natural gas but sometimes coal). Given that fossil fuels are not renewable resources, decreasing their use contributes directly to the net energy benefit derived from using ethanol rather than fossil fuels.
…(I)f the goal (or at least a goal) is to establish a domestically grown fuel without reliance on unsustainable fossil fuels, then technology innovations are needed to wean our ethanol plants off natural gas.
…Some energy efficiencies are gained by leveraging opportunities within local markets. Having a wet distillers grain purchaser in the local market significantly reduces energy needed to dry this valuable coproduct. Plants that are located close to an energy feedstock realize significant reductions in transportation costs. Poet LLC, for example, employs a solid waste fuel boiler at one biorefinery that consumes several hundred tons of waste wood chips each day, which would otherwise be headed to a landfill. The boiler also burns methane gas received via a pipeline from a local landfill. Other producers, such as Ace Ethanol LLC, have installed heat exchange equipment to reclaim waste heat. Recently, scientists from the USDA have used a commercial enzyme developed by Genecor to extract water from distillers grains, significantly reducing the amount of energy and water needed for ethanol production. READ MORE