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Abstract: The life cycle greenhouse gas (GHG) and fossil fuel benefits of black liquor recovery are analyzed. These benefits are due to the production of energy that can be used in the pulping process or sold, and the recovery of the pulping chemicals that would otherwise need to be produced from other resources. The fossil GHG emissions and non-renewable energy consumption of using black liquor in the kraft recovery system are approximately 90% lower than those for a comparable fossil fuel-based system. Across all scenarios, the systems relying on black liquor solids achieve a median reduction of approximately 140 kg CO2 eq./GJ of energy produced, compared to the systems relying on fossil fuels to provide the same energy and pulping chemical production functions. The benefits attributable to the recovery of pulping chemicals vary from 44% to 75% of the total benefit. Applied to the total production of kraft pulp in the U.S., the avoided emissions are equivalent to the total Scopes 1 and 2 emissions from the entire U.S. forest products industry. These results do not depend on the accounting method for biogenic carbon (because biogenic CO2 emissions are the same for the systems compared) and the results are valid across a range of assumptions about the displaced fossil fuel, the GHG-intensity of the electricity grid, the fossil fuels used in the lime kiln, and the level of cogeneration at pulp and paper mills. The benefits occur without affecting the amount of wood harvested or the amount of chemical pulp produced. [Copyright &y& Elsevier]

Abstract: A review of the four main wood energy sectors in the U.S. was conducted to explore historic trends and the impact of alternative energy prices and public policies on wood energy consumption. High oil prices have triggered the adoption of government regulation and financial incentives to promote greater use of wood energy over the last four decades. However, the amount of wood energy consumed in the U.S. industrial sector was driven mainly by the output of the pulp and paper products industry and not by energy prices or any particular public policy incentive. Residential consumption of wood energy was positively correlated with competing energy prices. Public policies seem to have had a greater impact on wood energy consumption in the electric power sector and over the last four decades have concentrated on promoting biopower with a recent shift to liquid cellulosic biofuels. High oil prices and a series of public policies such as tax credits, loans, grants, and renewable energy standards have resulted in higher consumption of wood energy from 2004 to 2009 in the residential, electric power and commercial sectors by an estimated 5, 2, and less than 1 percent annually, respectively. The impact of new federal programs such as the Biomass Crop Assistance Program remains to be observed. Continuation of public incentives and preferential regulations for renewable energy appears to be necessary for a steady increase in U.S. wood energy consumption. [Copyright &y& Elsevier]