Biofuel Potential for Loudoun County

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 . 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 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

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.

[DEP]U.S. Department of Energy briefing on BioFuel technology methods and trends.


Loudoun gas power plant application up for review Monday

There is a gas power plant application coming up for Board of Supervisors review this Monday, with public input starting at 5PM. So that you have an understanding of this application, here are some key points;

1. (From the PEC) The location of this industrial use conflicts with the County’s Comprehensive Plan. The Comp Plan currently calls for low density residential development (1 unit per 10 acres) at the location being considered, not an industrial power plant. This was a deliberate decision to protect cultural and natural resources in the immediate area, including the Goose Creek Reservoir which provides the surrounding region with drinking water. The public emphatically reaffirmed the vision for the entire Transition Area and this area in particular in a series of public hearings between 2005 and 2008.

2. The plant is primarily full-time (baseload) electricity generation (approx. 600 MW), with some peak-load (approx. 300 MW). The solar component is only 1 MW capacity (when the sun is directly overhead), so that is roughly equal to .25MW actual generation. Hence, the energy generated will be roughly 99.98% from fossil fuels. So the “hybrid” moniker is misleading at best.

3. Virginia imports almost 60% of it’s natural gas, producing 128,454 million cubic feet and consuming 300,000 mcf. So any claim of energy independence is unfounded.

4. The US peaked in natural gas production in 1973. While various current estimates purport large potential resources of shale-bound natural gas in the US, like other energy investment schemes, there has been a significant overestimation intended to bolster the stock value of the main holding company.

From The Oil Drum article “ExxonMobil’s Acquisition of XTO Energy: The Fallacy of the Manufacturing Model in Shale Plays“;

The manufacturing model developed in the Barnett Shale play (Fort Worth basin, Texas), where almost 14,000 wells have been drilled. The greatest number of commercially successful wells are located in two core areas or “sweet spots,” and results are not uniform or repeatable even within these core areas .

The overriding problem with most U.S. shale plays is the lack of any elements of natural reservoir rock. Shale typically has no effective (connected) porosity, and have permeabilities that are hundreds to thousands of times less than the lowest permeability tight sandstone reservoirs. Unless siltstone or sandstone interbeds are present within the shale that have better matrix porosity and permeability, all reservoir is artificial–it must be created by engineering brute force.

Much progress has been made with completion methods, but unless stimulation produces an extensive, micro-fractured rock face, long-term production at commercial volumes is unlikely.

The mainstream belief that shale plays have ensured North America an abundant supply of inexpensive natural gas is not supported by facts or results to date. The supply is real but it will come at higher cost and greater risk than is commonly assumed.

5. Any power generated by this plant will not reduce coal-fired power generation, as that production is cheaper and will continue to be utilized until caps on carbon emissions are instituted. Wind or solar from potential local or nearby sources would be less likely to be implemented, however.

6. Natural gas combustion in a 60% efficient combined cycle generator (like one of the ones proposed) produces about 40% of the carbon emissions that a typical coal plant produces.

7. Green Energy Partners has claimed 90% efficiency with their main combined cycle, though this presumes they would export the excess heat to nearby buildings. There are no buildings nearby that can readily take advantage of this potentially wasted heat (the Wegman’s complex over 2 miles away already has new, efficient HVAC systems that would hardly be ripped out and replaced).

8. One way “peaker” gas power plants can complement wind and solar power generation is through the ability to ramp up and down quickly as conditions vary. The current power plant configuration is predominantly baseload generation, however, with 1/3 of it’s generation as ‘peaker’.

The public hearing starts at at 5:00 PM at the first floor Board Room of the County Government Center. If you can’t attend, please send an email to the Board today.

Add to the discussion at the Sustainable Loudoun forum under Natural Gas Power Generation.