Wiley Interscience has published a study by a team led by Lee R. Lynd from the Thayer School of Engineering at Dartmouth College called “Comparative Analysis of Efficiency Environmental Impact and Process Economics for Mature Biomass Refining Scenarios” (a PDF download) comparing the fourteen most mature biomass refining process scenarios using both biological and thermochemical techniques for the production of fuels, power, and/or animal feed protein. The study covers the process efficiency, environmental impacts (inclusive of petroleum use), greenhouse gas emissions, and water use and importantly, economic profitability.

The study considers factors like fuel and electricity prices, feedstock costs, and capital structures. The processes range from only thermochemical electrical power generation achieving a process efficiency of 49% (energy out as power as a percentage of feedstock energy in), at a cost of $0.0575/kWh, which is competitive in much of the U.S. The other end of the combined processes reach efficiencies between 55 and 64%, or gasoline equivalent costs at $1.37 – $2.16 per gallon. The ranges of processes are studied with a standard set of input costs, facility scale projections and financial conditions.

The pleasant surprise is the combined processes in which biological and thermochemical process are combined with heat recovery. These designs result in efficiencies ranging from 61 to 80% and drove lower costs for the fuel sales to $0.96 to $1.24/gallon. That’s competitive to today’s gasoline or corn ethanol market.

Those scenarios integrating biological and thermochemical processing enable waste heat from the thermochemical process to power the biological process, resulting in higher overall process efficiencies than would otherwise be realized and those efficiencies are nearing equivalency with petroleum-based fuels in some cases.

That’s the good news. More good news is that you can download the PDF file until May without paying Wiley. The bad news is that on May 31, 2009 the free download will cease. Get your copy now.

The study is one part of an eight-part set of paper for the journal Biofuels, Bioproducts and Biorefining in a special edition. Two others are available for free download. One is The Role of Biomass In America’s Energy Future: Framing the Analysis and the other is Co-production of Ethanol and Power From Switchgrass.

Biomass Energy Pathways. Click image for more.

Biomass Energy Pathways. Click image for more.

The five “have to pay for them” papers are titled:

  • Large-scale Production, Harvest and Logistics of Switchgrass – Current Technology and Envisioning a Mature Technology
  • Performance and Cost Analysis of Future, Commercially Mature Gasification-based Electric Power Generation from Switchgrass
  • Large-scale Gasification-based Coproduction of Fuels and Electricity from Switchgrass
  • Protein Feeds Coproduction in Biomass Conversion to Fuels and Chemicals
  • Projected Mature Technology Scenarios for Conversion of Cellulosic Biomass to Ethanol with Coproduction Thermochemical Fuels, Power and/or Animal Feed Protein, and an editorial,
  • What Could be Possible With Mature Biofuels Technologies

Professor Lee Lynd is the driving force behind the RBAEF project and a major contributor to the Wiley special issue. He explains the background to the project, “The RBAEF project, which was launched in 2003, as the most comprehensive study of the performance and cost of mature technologies for producing energy from biomass to date. Involving experts from 12 institutions, it is jointly led by Dartmouth College, New Hampshire, and the Natural Resources Defense Council and is sponsored by the US Department of Energy, the Energy Foundation and the National Commission on Energy Policy. The RBAEF seeks to identify and evaluate paths by which biomass can make a large contribution to energy services in the USA and determine how we can accelerate biomass energy use. In addressing these issues, the study has focused on future, mature technologies rather than today’s technology.”

Lee R. Lynd.  Click image for more.

Lee R. Lynd. Click image for more.

What the study accomplishes is describing “mature biomass” refining such that processes can be highly competitive with fuels on today’s market. The studies do a good job of being thorough with all the major components for pricing and investment included. As with any generalization local factors will skew results for better or worse, but for policy, other research, education and public discourse these are very important papers. It’s just a pity that Wiley hasn’t sense enough to have the journal’s leading work readily accessible for the widest possible range of readers.

What one comes away with is that the most promising processes are combined together for maximum output. Adding biological fermentation with Fischer-Tropsch and other thermochemical methods with heat recovery all pointed to retaining and using the energy in the raw feed stock leads to selling not just fuels, but net electrical power as well. That extra earning power goes a very long way to stabilize a facilities cash flow, profit and competitiveness in selling fuel products.

Just to throw cooling upon the overheated heated debate that had misled the conventional wisdom is that the mature technologies reduce greenhouse gas emissions on a per ton basis. Simple as that.

Another bit worth mentioning is that tightly engineered facilities require modest amounts of water. Water as a process material collects outputs useful for energy production so water treatment is an economically rewarding enterprise. Making a lot of wastewater and disposing of it without gathering the resources contained is really throwing cost recoveries and profits away.

The assertion from the study suggests biofuels with electrical power production can be economically self-supporting in competition with oil as low as $30 per barrel oil. Now that might be so in some circumstances. Yet other conditions will apply for individual facilities, some to operate at a lower cost and others higher. But we are learning that oil in a worldwide economic downturn has trouble staying below $40. That would leave the sophisticated biomass facility with a 33% cushion to get to earnings with a $30 oil equivalency cost structure.

Suddenly those ethanol plants that are having difficulty are looking much more interesting as a lot of invested facility might be had for pennies on the dollar.

I want my ethanol fuel cell now!


2 Comments so far

  1. Upscale Home on September 29, 2010 3:08 PM

    Hey there. Awesome. I did not expect this on a Saturday. This is a great post. Thanks!

  2. aerospace on November 8, 2010 7:25 AM

    Thanks for an idea, you sparked at thought from a angle I hadn’t given thoguht to yet. Now lets see if I can do something with it.

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