The recent Green Energy Partners’ power plant application provides an excellent stimulus for us all to begin thinking about Loudoun’s energy future. A few weeks ago, several members of the business (including GEP), agricultural, and environmental community pooled their efforts to write a briefing on the subject of bio-fuels. We have submitted it to the Board of Supervisors as a “Friend of the Board” submission.
Bio-fuels have received a lot of attention in recent years, but the discussions are usually about corn-based ethanol, mid-western farmers, or massive industrial concerns like Archer-Daniels-Midland. The briefing our team submitted to the Board addresses the economic, agricultural, technical and environmental considerations of using bio-fuels as a potential component of our energy supply right here in Loudoun.
Some readers may object to the concept of using plants as a source of energy assuming it is not technically possible, or is not economically competitive with regular fossil fuels. But that may no longer be the case.
Plants are hydrocarbons, just like fossil fuels. Our coal resources were once plants which for the most part lived about 300 million years ago during the Carboniferous Period. Our petroleum resources were marine diatoms and coccolithophores and other phytoplankton. There are several maturing technologies for converting plants into diesel fuel, gas, lubricants, and even plastic. Some plants, such as algae, are nearly 70% oil by weight. Another plant that can be made into bio-fuels is switchgrass. Switchgrass looks a lot like hay, and is planted, grown, harvested, and stored just like hay – using the very same equipment, and the same types of land, and the same rainfall pattern – and a lot less fertilizer.
There is one difference between using fossil fuels and bio-fuels: bio-fuels recycle CO2 back to the atmosphere where the plants harvested it in the first place, instead of creating new atmospheric CO2 which happens when fossil fuels are burned. If Loudoun County used bio-fuels to generate all of our electricity, our CO2 creation would drop by about 29%.
From an economic and agricultural perspective, the new power plant will spend nearly $140 million per year on fuel. If that fuel was bio-fuel instead of fossil fuel, much of that $140 million per year would go to Loudoun’s farmers. It’s worth noting that Loudoun still has 140,000 acres of highly productive farmland, of which about 40,000 acres are devoted to hay production.
In addition to fueling the power plant biofuels could be used to run our cars, our school busses, our commuter busses, and our tractors and heat our homes.
The briefing we submitted to the Board of Supervisors can be downloaded from the Sustainable Loudoun website at http://www.sustainableloudoun.org . Hopefully, you will find it entertaining reading and well-researched. Our paper discusses the pluses and minuses including most importantly the energy recovered as a function of the energy that would need to be invested, i.e., the energy cost of the fuel. We have identified the most conservative estimates as our baseline.
In a 2005 study conducted by Pimental and Patzek [Pimentel], switchgrass production was analyzed for EROEI, with these results:
The average energy input per hectare for switchgrass production is only about 3.8 billion calories per year. With an excellent yield of 10 tons per hectare per year, this suggests for each one thousand calories invested as fossil energy the return is 11,000 calories — an excellent return.
So the energy recovered over the energy invested is about 11:1 for switchgrass production looks promising. The next question, of course, is how much energy it takes to convert that switchgrass to fuel and to distribute that fuel to the end-user. The task of making the conversion and distribution functions cost-competitive with fossil fuels is the subject of considerable research and development at the moment [DEP].
Of course we must also consider competing uses of our farm land such as growing food.
The bio-fuels briefing we prepared provides a readable, short, and very informative survey of the potential for a new bio-fuel economy here in Loudoun. You may be surprised by what you read, and get inspired to discuss it with other members of the Loudoun business, agricultural, and environmental communities. To join our list-serve e-mail discussion system, just send an e-mail to email@example.com. Please include the word “help” in the subject line, and we’ll send you instructions to join the list. To download the briefing from our website, just point your browser to http://www.sustainableloudoun.org.
Tom Pfotzer, Will Stewart and Tony Noerpel
[Pimentel] Ethanol Production Using Corn, Switchgrass, and Wood; Biodiesel Production Using Soybean and Sunflower. Pimental and Patzek, January 2005. http://www.c4aqe.org/Economics_of_Ethanol/ethanol.2005.pdf
[DEP]U.S. Department of Energy briefing on BioFuel technology methods and trends. http://hawaii.gov/dbedt/info/energy/renewable/bioenergy/kickoff/21-spaeth.pdf