Impacts on forestry of changing energy sources.

Abstract

Abstract Global reliance on the use of fossil fuels has increased dramatically over the past century but we are now at a crossroads. Questions have been raised about the long-term availability of the energy resource supply, as shown by the Hubbard Curve for petroleum. (Hirsch RL. The Shape of World Oil Peaking: Learning from Experience. Available from: URL: http://www.netl.doe.gov/energy-analyses/pubs/Peak_Shape_Study.pdf (accessed 15 May 2007).). Major petroleum-producing regions in the Middle East, parts of Africa and South America, as well as Russia are plagued by political and security concerns. As a result, the rising petroleum price is often associated with a rising security 'risk' premium. Global warming and the role of carbon dioxide (CO 2 ) emissions, which are tied directly to fossil fuel usage, further exacerbate an already overwhelmingly complex problem. Concerns about the future availability of traditional energy sources and their usability have given rise to the exploration and preliminary development of a number of alternative energy sources. Renewables provide opportunities, but perhaps largely for niche markets. For example, although solar energy often appears attractive, it continues to be relatively expensive (Borenstein S. Valuing the Time-varying Electricity Production of Solar Photovoltaic Cells. Center for the Study of Energy Markets Working Paper No. 142. University of California Energy Institute; 2005.) and best suited for specialized situations off the grid. Also, while wind and hydropower can be important energy sources, they also have serious limitations and locational constraints. One renewable energy source that offers significant advantages is biomass because it is renewable and is viewed as free from net 'greenhouse gas' (GHG) emissions, primarily CO 2 emissions. Although biomass energy does release CO 2 into the atmosphere, the general approach is to treat the biological system as a closed loop where emissions are viewed as subsequently sequestered in replacement biological growth. This system gives rise to the interpretation that there are no direct net CO 2 emissions associated with biomass as an energy feedstock, and consequently, no penalties are likely to be assessed. Widespread biomass use for energy would have land use implications, particularly on the condition of forests, both in the USA and especially in the developing world. This paper focuses on the possible uses of biological materials and biomass to produce bioenergy, the technologies that would be needed, and the possible impacts of alternative energy and bioenergy sources on forests and forestry.