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The increasing production of modern bioenergy carriers and biomaterials intensifies the competition for different applications of biomass. To be able to optimize and develop biomass utilization in a sustainable way, this paper first reviews the status and prospects of biomass value chains for heat, power, fuels and materials, next assesses their current and long-term levelized production costs and avoided emissions, and then compares their greenhouse gas abatement costs. At present, the economically and environmentally preferred options are wood chip and pellet combustion in district heating systems and large-scale cofiring power plants (75-81 US$ 2005 /tCO 2 -eq avoided ), and large-scale fermentation of low cost Brazilian sugarcane to ethanol (-65 to -53 $/tCO 2 -eq avoided ) or biomaterials (-60 to -50 $/tCO 2 -eq avoided for ethylene and -320 to -228 $/tCO 2 -eq avoided for PLA; negative costs represent cost effective options). In the longer term, the cultivation and use of lignocellulosic energy crops can play an important role in reducing the costs and improving the emission balance of biomass value chains. Key conversion technologies for lignocellulosic biomass are large-scale gasification (bioenergy and biomaterials) and fermentation (biofuels and biomaterials). However, both routes require improvement of their technological and economic performance. Further improvements can be attained by biorefineries that integrate different conversion technologies to maximize the use of all biomass components.

The demand for fossil fuels for non-energy purposes such as production of bulk chemicals is poorly understood. In this study we analyse data on non-energy demand and disaggregate it across key services or products. We construct a simulation model for the main products of non-energy use and project the global demand for primary fuels used as feedstocks and the resulting carbon emissions until 2100. The model is then applied to estimate the potential emission reductions by increased use of biomass, a more ambitious climate policy and advanced post-consumer waste management. We project that the global gross demand for feedstocks more than triples from 30 EJ in 2010 to over 100 EJ in 2100, mainly due to the increased demand for high value chemicals such as ethylene. Carbon emissions increase disproportionately (from 160 MtC per year in 2010 to over 650 MtC per year in 2100) due to greater use of coal, especially in ammonia and methanol production. If biomass is used, it can supply a large portion of the required primary energy and reduce carbon emissions by up to 20% in 2100 compared to the reference development. Climate policy can further reduce emissions by over 30%. Post-consumer waste management options such as recycling or incineration with energy recovery do not necessarily reduce energy demand or carbon emissions