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Manomet Biomass Sustainability & Carbon Policy Study. Manomet Center for Conservation Sciences Forest Guild Pinchot Institute for Conservation Biomass Energy Resource Center Independent Advisory Panel Presented by Thomas Walker 4 December 2009. Forests of Massachusetts.
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Manomet Biomass Sustainability & Carbon Policy Study Manomet Center for Conservation Sciences Forest Guild Pinchot Institute for Conservation Biomass Energy Resource Center Independent Advisory Panel Presented by Thomas Walker 4 December 2009
Forests of Massachusetts Planned Harvests Average Annual (1984-2009) Acres 25,000 Sawtimber 55 million board feet Other Biomass 150,000 green tons Source: MA forest cutting plans
Biomass Harvests and Forest Impacts Will permitting of proposed biomass plants lead to excessive, unsustainable harvesting that damages our forested ecosystems? ________________________________________ • Past biomass analysis focused too heavily on biological availability -- measures of annual net forest growth -- economic availability is a better indicator of potential impacts. • This is a function of three factors: • prices that biomass facilities can pay • harvesting and collection costs, and • willingness of forest landowners to increase harvests in response to offered prices. • Using realistic measures of future wood harvests, it is possible to evaluate the potential ecosystem impacts. • Nutrient depletion appears to be the biggest concern to date for MA forests. • Biodiversity impacts may also be an issue. • Is it necessary to modify forest cutting practice regulations to prevent damage to forests?
Biomass and the Carbon Cycle Will biomass energy development in MA lead to increases in greenhouse gas emissions? ____________________________________________ • A legitimate and complicated question -- past assumptions that trees re-sequester carbon and therefore biomass is ‘carbon friendly’ are overly simplistic. • Different sources of forest biomass fall along a carbon continuum: • Biomass from land clearing and conversion clearly increases greenhouse gas emissions -- mining trees instead of coal. • Biomass from ‘closed loop’ plantations on land that wouldn’t otherwise be forested will reduce emissions. • Biomass from natural forests in MA falls somewhere between these extremes. Some factors influencing which end of the continuum it’s closer to include: • Age, volume and growth rates for harvested stands. • Type of material harvested -- slash left to decay vs. trees that would have continued growing. • Rate of re-growth of harvested stands, potentially a function of management practices. • Differences in these factors manifest themselves in the timing of the re-sequestration of the carbon. • Also important is a clear understanding of the ‘business as usual’ baseline against which biomass is compared -- continued carbon sequestration in un-harvested forests and assumptions about energy sources that biomass replaces and the relative efficiency of new bio-energy facilities.
Key Study Questions For the Manomet Team___________________________________________________ • What are the economically available quantities of biomass in MA? • What are a representative set of future scenarios for biomass energy development -- large electric, CHP, thermal, other biomass-derived fuels -- given the estimated costs biomass supplies? • How would harvests under each of these scenarios affect the health of our forest ecosystems? Are additional state regulations needed to ensure the ecological sustainability of harvests? • What is the potential for changes in forest management to increase the rate of carbon storage or total stock of carbon stored in MA forests? • What are the net carbon implications of each of the future biomass energy development scenarios?
