{"id":5131,"date":"2017-06-26T07:39:16","date_gmt":"2017-06-26T07:39:16","guid":{"rendered":"http:\/\/task38.ieabioenergy.com\/?page_id=5131"},"modified":"2017-06-26T07:39:16","modified_gmt":"2017-06-26T07:39:16","slug":"graz-austria-1995","status":"publish","type":"page","link":"https:\/\/task38.ieabioenergy.com\/graz-austria-1995\/","title":{"rendered":"Graz, Austria 1995"},"content":{"rendered":"
Task XV: Greenhouse Gas Balances of Bioenergy Systems<\/b><\/p>\n
20-22 September 1995 – JOANNEUM RESEARCH, Institute of Energy Research Graz, Austria<\/p>\n
<\/p>\n
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Wednesday, 20 September 1995<\/strong><\/p>\n Biomass district heating plants in Maria Alm and Stra\u00dfwalchen (Salzburg)<\/p>\n Thursday, 21 September 1995<\/strong><\/p>\n Welcome and Introduction<\/strong> Research on Energy Costs and Carbon Sequestration Value of Timber and Wood Fuel Production in Britain<\/strong> Calculating the Carbon Balance of Forestry in New Zealand<\/strong> A Global Afforestation Program for Carbon Sequestration – Conclusions and Further Research Implications<\/strong> IEA Greenhouse Gas R&D Program: Work on Full Fuel Cycle Analysis of Fossil Fuel Power Generation<\/strong> Reducing CO2 Emissions by Substituting Biomass for Fossil Fuels<\/strong> Assessing the Contribution of Forest Bioenergy to the Carbon Budget of Canada’s Forests: A Scaling Problem<\/strong> Greenhouse Impact Expressed as Radiative Forcing Due to Bioenergy Fuel Chains<\/strong> Work in the U.S. on Biomass Fuels and Greenhouse Gas Emissions – Some Notes<\/strong> Full Fuel Cycle Carbon Balances of Bioenergy and Forestry Options; and: Report on the “Greenhouse Gases: Mitigation Options” Conference, London, 22-25 August 1995<\/strong> Evaluation Criteria for Carbon Dioxide Mitigating Projects in Forestry and Agriculture; and: Global Change and Boreal Forests: the Role of Forests in the Carbon Cycle – a Systems Approach with Special Focus on Nordic Countries<\/strong> Friday, 22 September 1995<\/strong><\/p>\n Task XV administrative matters:<\/strong><\/p>\n 1.) Final work program Task XV Analytical Framework for Greenhouse Gas Balances of Bioenergy Systems, Discussions<\/strong><\/p>\n <\/p>\n <\/p>\n <\/p>\n Analytical Framework for Greenhouse Gas Balances of Bioenergy Systems – Proceedings of a Workshop<\/i><\/b>, <\/a><\/p>\n Some authors have proposed forest management changes to enhance the offsetting of C emissions. Simulations of the effects of alternative forest management methods in Britain are strongly influenced by the C budgeting methodology employed. Due in part to differences in C-budgeting methods, bublished conclusions and recommendations about C-sequestration enhancement through changes in forest management differ sharply. Some studies suggest that changes in wood utilisation are potentially more important than changes in forest management. The sensitivity of results to changes in budgeting methodology requires that methodologies be consistent with objectives, and critical and objective evaluation of published C budget statistics. Conventions for modelling and reporting C budgets must be formulated. The diversity of forest types and roles, and the complexity of C flows, hamper the standardization of C budgeting methods.<\/p>\n <\/a><\/p>\n The New Zealand forest industry is based on an intensively managed plantation forest estate of 1.4 million hectares, which is predominantlyPinus radiata<\/i>. Information tools developed to assist in the management of these forests, include models used to evaluate silvicultural options at the stand and the estate level. Several of these models can be used in the calculation of carbon sequestration in the plantation forest estate. Some have been adapted for this purpose and others are still undergoing development. Less work has been done on the assessment of carbon emissions in the forest industry. The\u00a0 initiation of a modeling system to calculate the carbon balance of the forest industry in New Zealand has highlighted areas where information is lacking and suggested new approaches.<\/p>\n <\/a><\/p>\n CONCLUSION: The potential for enhancing global carbon sinks through a massive plantation program is limited by a variety of constraints. The available land of 345 million ha is substantially less than existing estimates of land that would be suitable (1.5 billion ha for plantations and 1 billion ha for agroforestry, respectively; Nilsson and Schopfhauser, 1995). A significant effect on the carbon content of the atmosphere would only be achieved after 40-50 years while the maximum carbon fixation rate of 1.5 Gt of carbon per year would only be reached about 60 years after the establishment of the plantations. By linking the afforestation program with bioenergy production and by doing so replacing fossil fuels, some 2 Gt could be offset. <\/a><\/p>\n Replacing fossil fuels with sustainably-produced biomass will reduce the net flow of CO2 to the atmosphere. We express the efficiency of this substitution in reduced emissions per unit of used land or biomass, and in costs of the substitution per tonne of C. The substitution costs are calculated as the cost difference between continued use of fossil fuels at current prices and the use of biomass, assuming that the biomass technologies are implemented when reinvestments in existing technologies are required. Energy inputs into biomass production and conversion are biomass-based, resulting in a CO2-neutral fuel cycle, while CO2 emissions from fossil fuels are estimated for the complete fuel cycles. Substituting biomass for fossil fuels in electricity and heat production is, in general, less costly and provides larger CO2 reduction per unit of biomass than substituting biomass for gasoline or diesel used in vehicles. For transportation, methanol or ethanol produced from short-rotation forests or logging residues provide larger CO2-emission reductions than rape methyl ester from rape seed, biogas from lucerne (alfalfa), or ethanol from wheat. Of these, methanol has the lowest emission-reduction costs. Increasing biomass use by 125 TWh\/yr, the estimated potential for increased utilization of logging residues, straw and energy crops, would eliminate more than half of the Swedish CO2 emissions from fossil fuels of 15 Mtonnes C in 1992.<\/p>\n <\/a><\/p>\n In this paper we shortly outline a method to estimate the greenhouse impact of energy production by calculating the radiative forcing caused by the emissions. Some examples of the results concerning bioenergy fuel chains are given and problems associated with the approach are discussed. The method and the examples are presented in more detail in (Savolainen et. al 1994a; 1994b). <\/a><\/p>\n Within the U.S., analysis of greenhouse gas emissions from biomass fuel systems is taking place in a number of institutions and with a number of objectives.Excursion<\/h2>\n
\nJosef Spitzer, JOANNEUM RESEARCH, Graz, Austria<\/p>\nPresentations by Invited Guests<\/h2>\n
\nRobert Matthews, Forestry Commission, Mensuration Branch, Alice Holt Lodge, United Kingdom<\/p>\n
\nJustin Ford-Robertson, New Zealand Forest Research Institute, Rotorua, New Zealand<\/p>\n
\nWolfgang Schopfhauser, International Institute for Applied Systems Analysis (IIASA), Laxenburg, Austria<\/p>\n
\nPaul Freund, IEA Greenhouse Gas R&D Program, Cheltenham, UK<\/p>\nPresentations by National Teams<\/h2>\n
\nLeif Gustavsson, Department of Environmental and Energy Systems Studies, Lund University, Sweden<\/p>\n
\nMike Apps, Department of Natural Resources Canada, Canadian Forest Service, Edmonton, Canada and Werner Kurz, Essa Technologies Ltd., Vancouver, Canada<\/p>\n
\nIlkka Savolainen, VTT-Energy, Espoo, Finland<\/p>\n
\nGregg Marland, Oak Ridge National Laboratory (ORNL), Oak Ridge, USA<\/p>\n
\nBernhard Schlamadinger, JOANNEUM RESEARCH, Graz, Austria<\/p>\n
\nBo Hektor, Swedish University of Agricultural Sciences, Uppsala, Sweden
\n<\/i><\/p>\nWorking Sessions<\/h2>\n
\n2.) Cooperation with Tasks XII, XIII
\n3.) Info\/data exchange
\n4.) Report to EC 36
\n5.) Workshop report
\n6.) State of bibliography
\n7.) Activities 1996
\n8.) Next workshop (date, location)
\n9.) Other items<\/p>\n\n
\nList of Participants<\/strong><\/h1>\n
\nWorkshop Proceedings<\/strong><\/h1>\n
\nB. Schlamadinger, M. Waupotitsch (eds.), 1996
\ncontains the following papers.<\/p>\n\n
\nThe Influence of Carbon Budget Methodology on Assessments of the Impacts of Forest Management on the Carbon Balance<\/i><\/a><\/li>\n
\nMethods Used to Calculate the Carbon Balance of the Forest Industry in New Zealand<\/i><\/a><\/li>\n
\nA Global Afforestation Program for Carbon Sequestration – Conclusion and Further Research Implications<\/i><\/a><\/li>\n
\nIEA Greenhouse Gas R&D Program: Work on Full Fuel Cycle Analysis of Fossil Fuel Power Generation<\/i><\/li>\n
\n\u00a0Reducing CO2 Emissions by Substituting Biomass for Fossil Fuels<\/a><\/i><\/li>\n
\nGreenhouse Impact Expressed as Radiative Forcing Due to Bioenergy Fuel Chains<\/i><\/a><\/li>\n
\nWork in the U.S. on Biomass Fuels and Greenhouse Gas Emissions: Some Notes<\/i><\/a><\/li>\n
\nGORCAM – A Tool to Calculate the Carbon Balance of Land Use and Bioenergy Strategies<\/i><\/a><\/li>\n
\nGlobal Change and Boreal Forest: The Role of Forests in the Carbon Cycle – a Systems Approach with Special Focus on Nordic Conditions<\/i><\/a><\/li>\n<\/ul>\n
\nThe Influence of Carbon Methodology on Assessments of the Impacts of Forest Management on the Carbon Balance<\/h2>\n
Robert W. Matthews<\/h3>\n
\nMethods Used to Calculate the Carbon Balance of the Forest Industry in New Zealand<\/h2>\n
Justin B. Ford-Robertson<\/h3>\n
\nA Global Afforestation Program for Carbon Sequestration – Conclusion and Further Research Implications<\/h2>\n
Wolfgang Schopfhauser<\/h3>\n
\nOver 100 years, the proposed global plantation program would sequester a total of some 104 Gt C in forest ecosystems and additionally it would offset some 40.6 Gt C through fossil fuel substitution. The maximum carbon fixation per year is substantially lower than the amount required to offset current carbon emissions of 3.2 (\u00b10.1) Gt\/yr (Dixon, et al.<\/i>, 1994). Furthermore, the maximum carbon fixation and offset is more than one-fourth, respectively one-third if the energy option is taken into account, of the annual release of CO2 of 6.3 (\u00b10.6) Gt\/yr (Dixonet al.<\/i>, 1994). Therefore large-scale plantations are unlikely to quickly stabilise the carbon content of the atmosphere. However, forest plantations would be only one of several means required to solve the CO2 emission problem.<\/p>\n
\nReducing CO2<\/sub> Emissions by Substituting Biomass for Fossil Fuels<\/h2>\n
L. Gustavsson, P. B\u00f6rjesson, B. Johansson, and P. Svenningsson<\/h3>\n
\nReducing CO2<\/sub> Emissions by Substituting Biomass for Fossil Fuels<\/h2>\n
J. Sinisalo, I. Savolainen<\/h3>\n
\nThe energy production chains considered in this paper are peat, forest residues, wood fron firtst thinnings of the forest, unused merchantable wood, short-rotation planted stand, and for comparison, coal nad natural gas.
\nThe impact of the caused emissions is calculated in terms of radiative forcing. The radiative forcing caused by the net emissions from an energy production chain were calculated using a REFUGE model. Radiative forcing is calculated on the basis of the concentration changes caused by the emissions and sinks. Instead of looking at the impacts of the energy production of one year, it is more insightful to consider the greenhouse impact of continuous energy production.
\nIn the very short term natural gas is a good option due to high energy value, but quite soon energy produced from forest residues and wood from first thinnings have smaller impact. Short rotation planted stands cause by far the smallest greenhouse impact during the first decades and have also the least impact in the long run. In the case of planted stands it is due to the fast regrowth of carbon stock. Forest residues and wood from first thinnings are efficient in this sense because of the relatively fast decay of residues in the forest assumed in the reference case (ie. the carbon released in combustion would be released into the atmosphere quite fast anyhow).
\nInitially unused merchantable wood causes as much radiative forcing as coal and peat, but later on its impact becomes even negative. This phenomenon is due to a combination of several factors: in the reference case the forest is by this time already fully grown and does not sequester more carbon, whereas in the energy production case it is still growning. In addition to this most of the carbon emitted during the combusion has already been transferred from the atmosphere into the ocean. Peat as an energy source seems to cause approximately as much radiative forcing as coal.<\/p>\n
\nWork in the U.S. on Biomass Fuels and Greenhouse Gas Emissions: Some Notes<\/h2>\n
Gregg Marland<\/i><\/h3>\n
\nTo illustrate the range of interest, I list below some of the studies underway now in the U.S. These are projects with different, yet similar, goals and similar, yet different, approaches. In each case the final goal is, ultimately, reducing net emissions of greenhouse gases in ways that are compatible with other institutional and societal objectives. The informal list below identifies host institutions, names at least one person at each, and offers a one or two-sentence description of activities. This does not purport to be a complete list of on-going activities in the U.S., but it does provide a beginning indication of some of the kinds of activities going on and their principal participants.<\/p>\n
\n