January and February 2007
FUEL FOR THOUGHT: America's High-Fiber Energy Future
Ready for this month’s energy quiz? Name an energy source that comes out of the ground and can be processed into liquid fuel suitable for transportation.
The answer: Woody biomass. Of course, until now, most of us have considered wood’s energy uses in a narrower light. Trees and residue get chipped into boiler fuel (hog fuel); hog fuel gets burned in boilers for traditional space heating or the generation of electricity; end of story.
But recently, a new narrative has formed within the forest industry, starring a concept called “total forest biorefinery.” The idea was presented recently in the American Forest and Paper Association’s “Agenda 2020” initiative. Basically, total forest biorefinery involves using existing pulp mills to produce transportation fuels—as well as a myriad of other biobased products that are currently made using fossil energy sources.
Squeezing Fuel from Wood
Forest biorefineries would use techniques like pyrolosis and gasification to produce synthetic fuels, along with a very clean burning Fischer-Tropsch diesel fuel. In addition, they would use enzymatic processes for ethanol production.
These new fuels are already in the development pipeline. A number of companies recently announced pre-commercial stages of development, and full commercialization of technologies for cellulosic ethanol and other transportation fuels could arrive within three years. What’s more, the potential infrastructure is already in place: Pulp mills that are now closed or underutilized could be retrofitted to produce liquid fuel.
Toting Up the Raw Material
Currently, only about six percent of U.S energy is derived from renewables. Half of that six percent comes from cogeneration— in other words, forest industries using wood residues and chips as an energy source in their industrial processes.
But if renewables are going to be a viable alternative to fossil fuels, and if biomass is going to be a substantial portion of renewables, then where will all that material come from? A study conducted by the Departments of Agriculture and Energy suggests that 1.3 billion bone dry tons (BDT) a year could be harvested from farms and forests. That’s .998 billion BDT from agriculture and .368 billion BDT from forestry sources. To put those numbers in perspective: 1.3 billion BDT would produce the same amount of energy that domestic crude oil produced in the U.S. in 1970.
The forest-based fuels in this estimate would come from hazardous fuel thinnings, logging, and other forest residues. If you add in the 18 billion cubic feet of wood harvested annually in the U.S., that .368 billion figure would skyrocket to almost a billion BDTs. Of course, no one is suggesting a shift from current higher value wood uses to energy—the marketplace of the future will determine shifts in product and output mixes.
At any rate, a vast amount of woody biomass could also come from short-rotation tree crops. These crops are ready for harvest in three to five years and can grow at the energy equivalent rate of three to 12 barrels of petroleum, per acre, annually. There is extensive non-forest land, not currently used for food, feed, or fiber production, available in the U.S. for planting of these short rotation trees.
There is also a tremendous volume of woody biomass obtainable through stand improvement work in our nation’s hardwood and softwood forests. Demolition wood, construction residues, and urban green waste could be added to the total. Lastly, the millions of downed trees from Hurricane Katrina could have been salvaged to produce energy.
A Crude Comparison
Unlike fossil fuel, biomass-based fuel is renewable. Once crude oil is pumped, refined, and used, it’s gone forever, but trees and crops keep growing back.
Biomass is also cleaner. When you turn plants into energy, the CO2 released in the process is taken up by the plants that replace them, resulting in zero net carbon emissions. By comparison, burning fossil fuels simply pumps more carbon into an already-overcrowded biosphere.
Just as important, biomass is more reliable. The events of September 11, 2001 alerted many of us that we pay a costly premium for our dependence on fossil fuels from volatile regions.
In short, energy from biomass helps our planet and our country. It could mean improved management of nonindustrial forestlands and increased incomes for farmers, forest owners, logging contractors, and forest industries. It could result in new alternative enterprises and enhanced economies for rural areas. (If biorefineries catch on, paper could well become a byproduct of pulp and paper mills.) Finally, biomass energy could mean more productive uses of marginal lands and the resolution of hazardous forest fuel buildups, as well as a boost to the effort to resolve air, water, and soil quality problems.
Support for Wood is Growing
Together with other categories of biomass-based energy, biomass-based fuels seem to have a bright future. After all, they’re part of a technology that’s reliable, sustainable, and non-polluting, not to mention immune from the shocks of global crisis — all reasons why political support is slowly gaining momentum.
In fact, President Bush mentioned woodchips as a source of energy in his last State of the Union address, and renewable energy is rumored to be a part of his upcoming address. In addition, the Pelosiled Congress has renewable energy high on its agenda. Some Capitol-watchers are betting that renewable energy evolves into a full-fledged bi-partisan initiative in the current session of Congress.
Gaining Consensus – Moving Forward
Not everyone has signed on to renewable technologies. What if renewables increase competition (and costs) for raw material supplies? That’s still a consideration for certain sectors of production agriculture
But other industry leaders embrace the idea of a renewable energy future. They see it as the right thing to do for the nation because it’s a way to enhance national security, improve the environment, and revitalize rural economies devastated by the forest policies of the past.
The movement is picking up speed, but as with any new technology, entry into the mainstream will be achieved by a combination of private initiative and national political will. The key is to become engaged in the process so that the policies developed through any Congressional legislation are as workable as possible for all.
This page was last updated on Tuesday, April 17, 2007