August 27, 2010

Truckin’: Got my biomass chips cashed in

Article reviewed:  Engineering considerations in road assessment for biomass operations in steep terrain

By J. Sessions, J. Wimber, F. Costales, and M. Wing, published in Western Journal of Applied Forestry. Vol. 25 pp. 144-153

The plot line: The authors of this article discuss the challenges and some solutions for transporting biomass material from forests to energy plants. They point out that roads designed in the past for hauling timber will not necessarily allow passage for the different transport vehicles that are necessary for modern biomass operations. Lots of different transport vehicles and trailers are available, each with slightly different road system requirements. What foresters should look for both in terms of equipment and road systems prior to conducting biomass operations are discussed in the article.   

Relevant quote: The focus of field assessment is to identify critical points on the road system… two important areas to identify are road width around sharp curves and the presence of steep grades.”

Relevance to landowners and stakeholders:

Biomass operations are kind of like sex in high school: Everyone’s talking about it, but no one is doing it (at least when I was in high school). I do know a few foresters who do it routinely (I’m talking about biomass operations now), but given the huge number of publications and news articles about biomass harvesting, you would think that all foresters are doing it. It certainly has a lot of appeal for landowners in western forests- it’s a potential source of renewable energy and could also help reduce high severity fire. But like most new technologies or ideas, the infrastructure and expertise needed to implement lags behind the concept.

One piece of the lagging infrastructure is the transportation system needed to get the biomass material from the forest to the energy plant. As the authors point out, landowners can not assume that if the road was built for hauling logs in the past, then it should be good enough for hauling biomass. A careful assessment of roads as well as an understanding of the type of equipment that is available in a given area is necessary before embarking (get it?) upon a biomass operation.

Relevance to managers:

The most critical thing to do when considering a biomass operation is to talk with the people who operate the equipment that you’ll be using. They know what they can and cannot handle when it comes to transportation. You’ll want to find out the following about their equipment (this is mainly with respect to the type of chip vans they have):

  • Do they have axle locks (“lockers”)? This makes a big difference when it comes to pulling loads up steep road pitches
  • Do they have mechanical (better) or airbag (worse) suspension systems?
  • What is the maximum grade they can handle, both when loaded and empty? What about for straight-aways versus turns?
  • What kind of traction do they have?
  • Are they willing to use assist vehicles to pull/push chip vans across difficult stretches?
  • What vertical clearance is required?
  • What kind of turnaround space is needed at the landing? A chip van might need a circle as wide as 70’ in diameter to easily turn around… that’s a lot of landing space and growing space to give up.

The paper provides lots of suggestions for how foresters can do quick road assessments to look for trouble spots that might be difficult for chip vans to navigate. My favorite is the method for finding out a road’s “coefficient of traction.” It involves driving in your pickup, slamming on the brakes, and seeing how far you skid. I have to try that someday. I call it the Dukes of Hazard test.

Critique and/or limitations (there’s always something, no matter how good the article is) for the pedants:

It’s hard to critique a technical review like this. The authors seem to know what they are writing about, and I learned a lot from the article. My only complaint is that they get heavy into technical jargon very early on without defining lots of terms. Also, there are some typos throughout.