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Abstract: The feasibility of deploying a socio-economic and environmental impact analysis for large-scale bioenergy production on a regional level is analyzed, based on a set of defined criteria and indicators. The analysis is done for La Pampa province in Argentina. The case study results in conclusions in how far the criteria can be verified ex ante based on available methodologies and data sources. The impacts are analyzed for two bioenergy chains (soybeans and switchgrass) for a set of defined land use scenarios. The carbon stock change for switchgrass ranges from 0.2 to 1.2tonC/ha/year and for soybean from −1.2 to 0tonC/ha/year, depending on the scenario. The GHG emission reduction ranges from 88% to 133% for the switchgrass bioenergy chain (replacing coal or natural gas) and from 16% to 94% for the soybean bioenergy chain (replacing fossil fuel) for various lifetime periods. The annual soil loss, compared to the reference land use system is 2–10ton/ha for the soybean bioenergy chain and 1–2ton/ha for the switchgrass bioenergy chain. In total, nine sustainability principles are analyzed. In the case of switchgrass, most environmental benefits can be achieved when produced on suitable land of abandoned cropland. Soybean production for bioenergy shows a good overall sustainability performance if produced on abandoned cropland. The production of switchgrass on degraded grassland shows socio-economic and environmental benefits, which is not the case for soybean production. The production of bioenergy production on non-degraded grassland is not preferred. It is concluded that the scenario approach enables understanding of the complexity of the bioenergy chain and the underlying factors influencing the sustainability principles. It is difficult to give ex ante a final conclusion whether a bioenergy chain is sustainable or not as this depends not only on the previous land use system but also on other factors as the selection of the bioenergy crop, the suitable agroecological zone and the agricultural management system applied. The results also imply that it is possible to steer for a large part the sustainability performance of a bioenergy chain during project development and implementation. Land use planning plays a key role in this process. [Copyright &y& Elsevier]

Abstract: This study focuses on the economic feasibility for large-scale biomass production from soybeans or switchgrass from a region in Argentina. This is determined, firstly, by estimating whether the potential supply of biomass, when food and feed demand are met, is sufficient under different scenarios to 2030. On a national level, switchgrass has a biomass potential of 99×106 (1.9 EJ) to 243×106 tdm (4.5 EJ)/year depending on the scenario. Soybean (crude vegetable oil content) production for bioenergy has a potential of 7.1×106 (0.25 EJ) to 13.8×106 tdm (0.5 EJ)/year depending on the scenario. The most suitable region (La Pampa province) to cultivate energy crop production is selected based on a defined set of criteria (available land for biomass production, available potential for both crops, proximity of logistics and limited risk of land use competition). The available potential for bioenergy in La Pampa ranges from 1.2×105 to 1.8×105 tdm/year for soybean production (based on vegetable oil content) and from 6.3×106 to 18.2×106 tdm/year for switchgrass production, depending on the scenario. Bioenergy chains for large-scale biomass production for export or for local use are further defined to analyse the economic performance. In this study, switchgrass is converted to pellets for power generation in the Netherlands or for local heating in Argentina. Soybeans are used for biodiesel production for export or for local use. Switchgrass cultivation costs range from 33–91US$/tdm (1€=1.47 US$ based on 19 February 2008). Pellet production costs are 58–143US$/tdm for local use and 150–296US$/tdm until delivery at the harbour of Rotterdam. Total conversion costs for electricity in the Netherlands from switchgrass pellets range from 0.06–0.08US$/kWh. Heating costs in Argentina from switchgrass pellets range from 0.02–0.04US$/kWh. Soybean cultivation costs range from 182–501US$/tdm depending on the scenario. Biodiesel production costs are 0.3–1.2 US$/l for local use and 0.5–1.7 US$/l after export to the Netherlands. Key parameters for the economic performance of the bioenergy chains in La Pampa province are transport costs, cultivation costs, pre-processing and conversion costs and costs for fossil fuels and agricultural commodities. [Copyright &y& Elsevier]

Abstract: This article investigates technical possibilities and performances of flexible integrated gasification polygeneration (IG-PG) facilities equipped with CO2 capture for the near future. These facilities can produce electricity during peak hours, while switching to the production of chemicals during off-peak hours. Several simulations were performed to investigate the influence of substituting feedstock and production on IG-PG facility output, load and efficiency. These simulations were done using a detailed AspenPlus simulation model of a Shell entrained flow gasifier combined with conversion facilities. In this model carbon-rich feedstocks (oil residues, coal and biomass) were converted to a variety of products (H2, electricity, FT-liquids, methanol and urea) using state-of-the-art technology. The size of the gasifier was limited to the equivalent of 2000MWth Il #6 coal input. Overall efficiency of the simulated non-flexible configurations to convert pure coal or pure wood pellets to electricity (40%HHV vs 38%HHV), FT-liquids (60%HHV vs 55%HHV), methanol (53%HHV vs 49%HHV) or urea (51%HHV vs 47%HHV) are in good agreement with the literature. Using torrefied wood pellets instead of pure wood pellets reduces the penalty drop in efficiency compared to coal. Moreover, torrefied wood pellets have superior energetic density, handling and feeding compared to wood pellets. In this analysis, the H2:CO ratio of the sweet syngas was fixed to match FT-liquids criterion. As a result, overall CO2 capture rates are low, around 56–65%, depending on the feedstock used. Still, especially with FT-liquids and methanol production, CO2 emissions at the facility are significantly reduced; less than 20% of the carbon feedstock entering the facility is emitted with the flue gas. Applying biomass and CO2 capture shows great opportunities to produce CO2-neutral electricity or chemicals. When the biomass fraction exceeds 40% on an energy basis, production is CO2-neutral, independent of what is produced. Biomass can be co-fed up till 50% on an energy basis. Higher fractions cause significant fouling on cooling equipment. A small part-load penalty is observed during the substitution of coal by biomass. When changing from pure coal to pure wood pellets, the power case suffers a 2.5% efficiency drop, while all three chemical cases have an efficiency drop of less than 1%. At the same time total output is reduced to 67–69%, mainly because of the lower energy density of biomass. By over-dimensioning the gasifier and gas cleanup and optimisation section this drop can be eliminated. The syngas can be tailored to the desired composition regardless of the used feedstock. Therefore, the chemical conversion sections only have to cope with a reduction in syngas flow and not with a change in syngas composition. Altering production between chemicals and electricity is possible, although the load of the conversion sections should remain between 40% and 100% to prevent operational problems. This gives a high degree of flexibility. Complete substitution between chemical and power production while using the same feedstock is possible for the methanol and urea cases. The FT-liquids case is restricted to 60–100% load of the chemical conversion section to prevent that the gas turbine load is reduced below 40%. The economic aspects of flexible IG-PG facilities are addressed in part B. [Copyright &y& Elsevier]