The Potential of Wood Energy in the United States
An article in the March 13 edition of Science ("Wood Energy in America") finds that wood energy can provide economic, social, and environmental benefits for many areas of the United States while lowering greenhouse gas emissions, reducing dependence on foreign oil, and stimulating local economies. Duke University professor Daniel deB. Richter led the team of ecologists, foresters, and energy professionals from a consortium of institutions who participated in the study. The authors argue advanced wood combustion (AWC), which can provide clean heat, cooling, and electricity, can be rapidly implemented in U.S. communities with sustainable wood supplies.
To expand the wood energy economy, the authors recommend three initiatives. First, make AWC the preferred system of power for new construction and renovations in counties with sustainable wood feedstocks. Second, utilize diseased trees and wood from construction sites and other sources of urban wood as a source of fuel. Lastly, take advantage of district-energy systems tied to AWC by supplying heat from a centralized location to a greater number of sites.
The U.S. lags far behind Europe in terms of adopting wood energy, but the use of wood energy is increasing in the domestic energy market. While AWC may not be sustainable or cost-effective for all areas of the U.S., the authors contend adequate wood supplies exist to fuel AWC facilities serving towns, industrial complexes, schools, and other institutions in many regions, particularly in the Southeast, Northeast, and West. Downtown St. Paul, Minnesota, for example, relies almost exclusively on wood energy for its heat and power. In the south, Southern Company was just granted permission to convert a Georgia coal-fired power plant to a renewable wood biomass-fired plant. The 96 megawatt plant will draw on biomass from a 100 mile radius and power 600,000 homes, making it one of the largest biomass plants in the country. On a smaller scale, wood pellet stoves have become popular in the Northeast and Northwest, especially as home heating oil prices spiked recently.
All indications suggest wood energy use will continue to grow in the U.S., especially if federal policies are enacted that drive the energy market toward low-carbon, renewable sources - such as a national renewable energy standard (RES) or legislation to cap and trade emissions of greenhouse gases. According to a recent study by the Southern Alliance for Clean Energy, biomass represents two thirds of the southeast's near-team potential for expanding renewable energy. In one of the most comprehensive national feedstock studies (the "billion ton" study) to date, DOE and USDA determined American forests can sustainably produce 368 million dry tons of wood for energy per year.
These findings are encouraging for the biomass industry, but more, in-depth study is certainly needed to determine how these resources can be developed sustainably and economically. Biopower facilities and wood pellet manufacturers currently rely primarily on sawdust and residues left over from wood products manufacturing, logging, and other 'waste' sources, but these sources are limited and highly dependent on fluctuating markets for traditional wood products. There is concern that a rapidly expanding bioenergy industry will eventually compete for pulpwood and other primary forest resources. Competition between the different wood products industries could result in over-harvesting and higher prices for bioenergy feedstock. As cellulosic ethanol becomes commercially viable, there will be even greater competition among bioenergy facilities and other wood-users for limited feedstocks. Eventually, some bioenergy applications could be priced out of the market altogether, especially if the price of solar, wind, and other renewable sources of energy continue to fall. Basic market forces will sort out some of this demand, but an F & W Special Report (Thomas, M. 2009. "New Industries Compete for Small Trees; Is Field Level?" F &W Forestry Services, Inc. Special Report: Winter 2009: 4-6.) warns that overlapping government incentives and mandates may artificially grow the industry beyond a level that is ecologically and economically sustainable.
It is unclear how big a role wood will play in addressing the nation's energy and climate challenges in the coming decades, but it shows significant promise for the short- to mid-term for reducing greenhouse gas emissions and meet renewable energy goals quickly, cleanly, efficiently, and affordably. Finding a sustainable balance and establishing a sufficient policy framework to encourage its development will be paramount to the future of wood energy in the United States.