U.S. Department of Energy Office of Biological and Environmental Research

BER Research Highlights


Diverse Biofeedstocks Have High Ethanol Yields and Offer Biorefineries Flexibility
Published: November 09, 2018
Posted: January 24, 2019

Evidence suggests that biorefineries can accept various feedstocks without negatively impacting the amount of ethanol produced per acre.

The Science
Biorefineries are picky eaters. They only consume one or two types of plant matter. Researchers processed and experimentally measured ethanol production from five different herbaceous feedstocks. They examined two annuals (corn stover and energy sorghum) along with three perennials (switchgrass, miscanthus, and restored prairie). They determined that a lignocellulosic ethanol refinery could use a range of plant types without having a major impact on the amount of ethanol produced per acre, or per land area.

The Impact
Many biorefineries consume one, or sometimes two, feedstocks grown and harvested nearby. The feedstock contains lignocellulose. That chemical is processed and fermented into biofuels or bioproducts. Accepting a variety of feedstocks could improve the refinery’s environmental footprint, economics, and logistics. The team’s study showed that a lignocellulosic refinery could be relatively agnostic in terms of the feedstocks used.

Summary
Refineries to convert biomass into fuels often rely on just one feedstock. If the refineries could accept more than one feedstock, it would greatly benefit refinery operation. Scientists at the Great Lakes Bioenergy Research Center investigated how five different feedstocks affected process and field-scale ethanol yields. Two annual crops (corn stover and energy sorghum) and three perennial crops (switchgrass, miscanthus, and restored prairie) were pretreated using ammonia fiber expansion, hydrolyzed, and fermented separately using yeast or bacteria. They found that both biomass quality (chemical composition, moisture content, etc.) and biomass yield affected how much ethanol each acre (or land area) produces. However, the effect differed. Biomass quality was the main driver for the ethanol yields for high-yielding crops, such as switchgrass. Biomass yield was the main driver for the ethanol yields for low-productivity crops, such as corn stover. Therefore, to increase ethanol yield for high-yielding crops, focusing efforts on improving biomass quality or conversion efficiency may be prudent. For low-yielding crops, focusing on increasing biomass yield may be the best strategy. When measuring the amount of ethanol produced during fermentation, most feedstocks fell within a similar range, especially when scientists used bacteria to ferment the biomass. In total, the results of this study suggest that a lignocellulosic refinery may use a variety of feedstocks with a range of quality without a major negative impact on field-scale ethanol yields.

Contact
Program Manager
N. Kent Peters
Department of Energy, Office of Science Office of Biological and Environmental Research
kent.peters@science.doe.gov, (301) 903-5549

Principal Investigator
Rebecca G. Ong
Michigan Technological University
rgong1@mtu.edu, (906) 487-2662

Funding
The Department of Energy, Office of Science, Office of Biological and Environmental Research Great Lakes Bioenergy Research Center funded this research

Publications
Y. Zhang, L.G. Oates, J. Serate, et al., “Diverse lignocellulosic feedstocks can achieve high field-scale ethanol yields while providing flexibility for the biorefinery and landscape-level environmental benefits.” GCB Bioenergy (2018). [DOI: 10.1111/gcbb.12533]

Topic Areas:

  • Research Area: Plant Systems and Feedstocks, Plant-Microbe Interactions
  • Research Area: Sustainable Biofuels and Bioproducts
  • Research Area: DOE Bioenergy Research Centers (BRC)

Division: SC-23.2 Biological Systems Science Division, BER

 

BER supports basic research and scientific user facilities to advance DOE missions in energy and environment. More about BER

Recent Highlights

Aug 24, 2019
New Approach for Studying How Microbes Influence Their Environment
A diverse group of scientists suggests a common framework and targeting of known microbial processes [more...]

Aug 08, 2019
Nutrient-Hungry Peatland Microbes Reduce Carbon Loss Under Warmer Conditions
Enzyme production in peatlands reduces carbon lost to respiration under future high temperatures. [more...]

Aug 05, 2019
Amazon Forest Response to CO2 Fertilization Dependent on Plant Phosphorus Acquisition
AmazonFACE Model Intercomparison. The Science Plant growth is dependent on the availabi [more...]

Jul 29, 2019
A Slippery Slope: Soil Carbon Destabilization
Carbon gain or loss depends on the balance between competing biological, chemical, and physical reac [more...]

Jul 15, 2019
Field Evaluation of Gas Analyzers for Measuring Ecosystem Fluxes
How gas analyzer type and correction method impact measured fluxes. The Science A side- [more...]

List all highlights (possible long download time)