Search

The increasing production of bio-based plastics calls for thorough environmental assessments. Using life cycle assessment, this study compares European supply of fully bio-based high-density polyethylene and partially bio-based polyethylene terephthalate from Brazilian and Indian sugarcane ethanol with production of their petrochemical counterparts in Europe. Bio-based polyethylene results in greenhouse gas emissions of around −0.75 kg CO 2eq /kg polyethylene , i.e. 140% lower than petrochemical polyethylene; savings on non-renewable energy use are approximately 65%. Greenhouse gas emissions of partially bio-based polyethylene terephthalate are similar to petrochemical production (±10%) and non-renewable energy use is lower by up to 10%, partly due to the low bio-based content of the polymer. Assuming that process energy is provided by combined heat and power reduces the greenhouse gas emissions of partially bio-based polyethylene terephthalate production to a range from −4% (higher) to 15% (lower) compared to petrochemical polyethylene terephthalate depending on the methodological choices made. Production from Brazilian ethanol leads to slightly higher impacts than production from Indian ethanol due to dampening effects of allocation on Indian ethanol produced from sugarcane molasses, different sugarcane pre-harvesting practices and inter-continental transport of Brazilian ethanol to India. Internal technical improvements such as fuel switch, new plants and best available technology offer savings up to 30% in greenhouse gas emissions compared to current production of petrochemical polyethylene terephthalate. The combination of some of these measures and the use of biomass for the supply of process steam can reduce the greenhouse gas emissions even further. In human health and ecosystem quality, the impact of the bio-based polymers is up to 2 orders of magnitude higher, primarily due to pesticide use, pre-harvesting burning practices in Brazil and land occupation. When improvements are assumed across the supply chain, such as pesticide control and elimination of burning practices, the impact of the bio-based polymers can be significantly reduced. Realising such improvements will minimise the greenhouse gas and other emissions and resource use associated with bio-based polyethylene terephthalate and will allow to alleviate further pressure on fragile ecosystems. [ABSTRACT FROM AUTHOR]

Forest biomass is one of the main contributors to the EU's renewable energy target of 20% gross final energy consumption in 2020 (Renewable Energy Directive). Following the RED, new sustainability principles are launched by the European energy sector, such as the Initiative Wood Pellet Buyers (IWPB or SBP). The aim of our study is the investigation of the quantitative impacts from IWPB's principles for forest biomass for energy only. We deploy a bottom up method that quantifies the supplies and the costs from log harvest until forest chip delivery at a domestic consumer. We have a reference situation with existing national (forest) legislation and voluntary certification schemes (scenario 1) and a future situation with additional criteria based on the IWPB principles (scenario 2). Two country studies were selected for our (2008) survey: one in Finland with nearly 100% certification and one in Leningrad province with a minor areal share of certification in scenario 1. The sustainable potential of forest resources for energy is about 54 Mm 3 (385 PJ) in Finland and about 13.5 Mm 3 (95 PJ) in Leningrad in scenario 1 without extra criteria. The potential volumes reduce considerably by maximum 43% respectively 39% after new criteria from the IWPB, like a minimum use of sawlogs, stumps and slash for energy, and by an increased area of protected forests (scenario 2A Maximum extra restrictions). In case sawlogs can be used, but instead ash recycling is applied after a maximum stump and slash recovery (scenario 2B Minimum extra restrictions), the potential supply is less reduced: 5% in Finland and 22% in Leningrad region. The estimated reference costs for forest chips are between €18 and €45 solid m −3 in Finland and between €7 and €33 solid m −3 in the Leningrad region. In scenario 2A, the costs will mainly increase by €7 m −3 for delimbing full trees (Finland), and maximum €0.3 m −3 for suggested improved forest management (Leningrad region). In scenario 2B, when ash recycling is applied, costs increase by about €0.3 to €1.6 m −3 , depending on the rate of soil contamination. This is an increase of 2%, on top of the costs in scenario 2A. [ABSTRACT FROM AUTHOR]

Abstract: This paper determines the energy consumption ratio and overall bio-energy production costs of micro-algae cultivation, harvesting and conversion to secondary energy carriers, thus helping to clarify future perspectives of micro-algae production for energy purposes. A limitation growth model is developed, which determines the productivity of micro-algae for different climate profiles. Total direct and indirect energy consumption ratios for the production of heat, fuels and electricity derived from micro-algae are calculated. Overall direct energy consumption ratio for raceway ponds is 0.06 for the optimal case, indirect energy consumption ratio for that case is 0.74. Direct energy consumption ratio in horizontal tubular systems is 0.32 for the optimal case, indirect energy consumption ratio for that case is 117. The implementation of different improvement options could reduce the indirect energy consumption ratio by fifty percent for both raceway ponds and horizontal tubular systems in the optimistic scenario. Prominent elements of the energy consumption ratios are carbon dioxide supply for raceway ponds and circulation power consumption for horizontal tubular systems. The lower end of fuel production cost calculated for raceway ponds is 136€2010/GJ and 153€2010/GJ for horizontal tubular systems (non-renewable gasoline and diesel is about 5–20€/GJ). Considering possible improvement options overall bio-energy production costs could be reduced by one-fourth. Current results suggest that micro-algae cultivation is not suitable for dedicated bio-energy production in considered cultivation, harvesting and conversion options. Coproduction of bio-energy with high-value products are more viable, but is not considered in this research. [Copyright &y& Elsevier]

Abstract: Central and Eastern European countries (CEEC) have a substantial biomass production and export potential. The objective of this study is to assess whether the market for biofuels and trade can be profitable enough to realize a supply of biofuels from the CEEC to the European market and to estimate the cost performance of the energy carriers delivered. Five NUTS-2 (Nomenclature d''Unités Territoriales Statistiques) regions with high biomass production potentials in Poland, Romania, Hungary and the Czech Republic were analysed for biofuel export options. From these regions pellets from willow can be provided to destination areas in Western European countries (WEC) at costs of 105.2–219.8€t−1. Ethanol can be provided at 11.95–20.89€ per GJ if the biomass conversion is performed at the destination areas in the WEC or at 14.84–17.83€ GJ−1J if the biomass to ethanol conversion takes place (at small scale) at the CEEC region where the biomass is produced. Short sea shipping shows most cost advantages for longer distance international transport compared to inland waterway shipping and railway. Another reason for lower biofuel supply costs are shorter distances between the regions of biomass production and the destination areas. Therefore the Szczecin region in Poland, closely located to the Baltic Sea, shows a better economic performance for long distance trade of biomass production than the selected region in Hungary (‘land-locked’). It is concluded that in future key CEEC regions can supply (pre-treated) biomass and biofuels to the European market at cost levels, which are sound and attractive to current and expected diesel and gasoline prices. [Copyright &y& Elsevier]

Abstract: A methodology for the assessment of biomass potentials was developed and applied to Central and Eastern European countries (CEEC). Biomass resources considered are agricultural residues, forestry residues, and wood from surplus forest and biomass from energy crops. Only land that is not needed for food and feed production is considered as available for the production of energy crops. Five scenarios were built to depict the influences of different factors on biomass potentials and costs. Scenarios, with a domination of current level of agricultural production or ecological production systems, show the smallest biomass potentials of 2–5.7EJ for all CEEC. Highest potentials can reach up to 11.7EJ (85% from energy crops, 12% from residues and 3% from surplus forest wood) when 44 million ha of agricultural land become available for energy crop production. This potential is, however, only realizable under high input production systems and most advanced production technology, best allocation of crop production over all CEEC and by choosing willow as energy crops. The production of lignocellulosic crops, and willow in particular, best combines high biomass production potentials and low biomass production costs. Production costs for willow biomass range from 1.6 to 8.0€/GJ HHV in the scenario with the highest agricultural productivity and 1.0–4.5€/GJ HHV in the scenario reflecting the current status of agricultural production. Generally the highest biomass production costs are experienced when ecological agriculture is prevailing and on land with lower quality. In most CEEC, the production potentials are larger than the current energy use in the more favourable scenarios. Bulk of the biomass potential can be produced at costs lower than 2€/GJ. High potentials combined with the low cost levels gives CEEC major export opportunities. [Copyright &y& Elsevier]

Abstract: It is expected that international biomass trade will significantly increase in the coming years because of the possibly lower costs of imported biomass, the better supply security through diversification and the support by energy and climate policies of various countries. Concerns about potential negative effects of large-scale biomass production and export, like deforestation or the competition between food and biomass production, have led to the demand for sustainability criteria and certification systems that can control biomass trade. Because neither such criteria and indicator sets nor certification systems for sustainable biomass trade are yet available, the objective of this study is to generate information that can help to develop them. For these purposes, existing certification systems, sets of sustainability criteria or guidelines on environmental or social sound management of resources are analyzed with the purpose to learn about the requirements, contents and organizational set ups of a certification system for sustainable biomass trade. First, an inventory of existing systems was made; second, their structures were analyzed. Key finding from the analysis of internationally applied certification systems was that they are generally led by an international panel that represents all countries and stakeholders involved in the biomass production and trade activities. In third and fourth steps different approaches to formulate standards were described and a list of more than 100 social, economic, ecological and general criteria for sustainable biomass trade was extracted from the reviewed systems. Fifth, methods to formulate indicators, that make sustainability criteria measurable, and verifiers that are used to control the performance of indicators are described. It is recommended to further develop the criteria and indicator (C&I) sets for sustainable biomass trade by involvement of the relevant stakeholders (e.g. biomass producer and consumer) and the analysis of local conditions (e.g. local production potentials and limits, and preferences of local people). [Copyright &y& Elsevier]

Whether the use of industrial wood pellets for bioenergy is part of the problem of climate change or part of the solution to climate change has been heavily debated in the academic and political arena. The uncertainty around this topic is impeded by contradicting scientific assessments of carbon impacts of wood pellet use. Spatially explicit quantification of the potential carbon impacts of increased industrial wood pellet demand, including both indirect market and land-use change effects, is required to understand potential negative impacts on carbon stored in the landscape. Studies that meet these requirements are scarce. This study assesses the impact of increased wood pellet demand on carbon stocks in the landscape in the Southern US spatially explicitly and includes the effects of demand for other wood products and land-use types. The analysis is based on IPCC calculations and highly detailed survey-based biomass data for different forest types. We compare a trend of increased wood pellet demand between 2010 and 2030 with a stable trend in wood pellet demand after 2010, thereby quantifying the impact of increased wood pellet demand on carbon stocks in the landscape. This study shows that modest increases in wood pellets demand (from 0.5 Mt in 2010 to 12.1 Mt in 2030), compared to a scenario without increase in wood pellet demand (stable demand at 0.5 Mt), may result in carbon stock gains of 103–229 Mt in the landscape in the Southern US. These carbon stock increases occur due to a reduction in natural forest loss and an increase in pine plantation area compared to a stable-demand scenario. Projected carbon impacts of changes in wood pellet demand were smaller than carbon effects of trends in the timber market. We introduce a new methodological framework to include both indirect market and land-use change effects into carbon calculations in the landscape. • Whether wood pellets are reducing or exacerbating climate change is heavily debated. • This spatially explicit study includes indirect effects of markets and land-use. • A modest increase in wood pellet demand result in carbon stock gains of 103–229 Mt. • Carbon gains are due to pine plantation expansion and natural forest conservation. [ABSTRACT FROM AUTHOR]

This study aimed to analyze whether, and how, uncertainty influences the layout and costs of a CO 2 transportation network. The case without uncertainty is modelled with a perfect foresight (PF) model and with uncertainty with the real option approach (ROA). In this study, uncertainties in the CO 2 price, tariff received per tonne of CO 2 transported, the willingness, probability and moment that sources join the CO 2 transportation network are incorporated in the analysis. The results show that uncertainty leads to higher required CO 2 prices before investments in carbon dioxide capture and storage (CCS) are made. With a volatility of 47% in the CO 2 price, the required CO 2 price almost triples in comparison with the net present value approach. Hence, under uncertainty less sources are retrofitted with CCS and less CO 2 is captured and stored over time. For instance, for the analyzed case study 31 Mt and 137 Mt CO 2 is projected to be captured in the base scenario of ROA and PF model, respectively, in the period 2015–2050. If the volatility of the CO 2 price is reduced with 50%, 96 Mt is projected to be captured in the ROA, which is still about one third less than in the PF model. Furthermore, the results show that uncertainty leads to less development of trunklines. All this leads to an increase in the transport and storage costs. For instance, for our case study, the average CO 2 transport and storage costs in 2050 increase from 2.8 €/t to 13 €/t in the base scenario of the ROA compared to the PF model. If the volatility is reduced with 50%, the transport and storage costs decrease to 7.5 €/t in the ROA, which is still 2.5 times as much as in the PF model. Our findings indicate that the implementation of CCS can best be stimulated by reducing the volatility of the CO 2 price, reducing capture costs and facilitating cooperation between nearby sources. [ABSTRACT FROM AUTHOR]

Abstract: In the face of climate change that may result from greenhouse gas (GHG) emissions, the scarcity of agricultural land and limited competitiveness of biomass energy on the market, it is desirable to increase the performance of bioenergy systems. Multi-product crops, i.e. using a crop partially for energy and partially for material purposes can possibly create additional incomes as well as additional GHG emission reductions. In this study, the performance of several multi-product crop systems is compared to energy crop systems, focused on the costs of primary biomass fuel costs and GHG emission reductions per hectare of biomass production. The sensitivity of the results is studied by means of a Monte-Carlo analysis. The multi-product crops studied are wheat, hemp and poplar in the Netherlands and Poland. GHG emission reductions of these multi-product crop systems are found to be between 0.2 and 2.4Mg CO2eq/(hayr) in Poland and 0.9 and 7.8Mg CO2eq/(hayr) in the Netherlands, while primary biomass fuel costs range from −4.1 to −1.7€/GJ in the Netherlands and from 0.1 to 9.8€/GJ in Poland. Results show that the economic attractiveness of multi-product crops depends strongly on material market prices, crop production costs and crop yields. Net annual GHG emission reductions per hectare are influenced strongly by the specific GHG emission reduction of material use, reference energy systems and GHG emissions of crop production. Multi-product use of crops can significantly decrease primary biomass fuel costs. However, this does not apply in general, but depends on the kind of crops and material uses. For the examples analysed here, net annual GHG emission reductions per hectare are not lowered by multi-product use of crops. Consequently, multi-product crops are not for granted an option to increase the performance of bioenergy systems. Further research on the feasibility of large-scale multi-product crop systems and their impact on land and material markets is desirable. [Copyright &y& Elsevier]

Management strategies for loblolly pine ( Pinus taeda ) plantations in the Southeastern USA can be adapted to fulfill both the demand for wood products and for bioenergy. This study quantifies the impact of plantation management choices on the cumulative carbon balance and the net present value of loblolly pine plantations at the stand level, as well as the wood supply cost for bioenergy production for these different management strategies. The strategies assessed (conventional, additional thinning and short rotation) are characterised by planting density, thinning age and rotation period, each with and without collection and utilization of slash residues for bioenergy. The total wood supply costs for bioenergy include the cultivation, harvesting and transport costs for small diameter trees and slash. The results show that the carbon balance after 100 years is 205 (247), 214 (268) and 149 (195) Mg ha −1 for the conventional, additional thinning, and short rotation loblolly pine plantation management strategies (within parentheses: same strategies with slash utilization). The conventional strategy has the lowest wood supply costs for bioenergy, 47 (46) $ Mg −1 pulpwood, followed by the additional thinning strategy, 50 (49) $ Mg −1 pulpwood, and 54 (52) $ Mg −1 pulpwood for the short rotation management strategy. In conclusion, switching from the current conventional strategy without the utilization of slash for bioenergy to an additional thinning strategy with the use of slash increases the overall carbon accumulation by about 31%, at marginally higher wood supply cost. Adapting plantation management strategies can have a positive effect on the economic performance and on the carbon balance of loblolly pine plantations. Integration of wood supply for bioenergy and traditional forestry sectors can lead to co-benefits in terms of cost reduction and carbon accumulation. [ABSTRACT FROM AUTHOR]

This study assessed the feasibility of mobilising maize and wheat residues for large-scale bioenergy applications in South Africa by establishing sustainable residue removal rates and cost of supply based on different production regions. A key objective was to refine the methodology for estimating crop residue harvesting for bioenergy use, while maintaining soil productivity and avoiding displacement of competing residue uses. At current conditions, the sustainable bioenergy potential from maize and wheat residues was estimated to be about 104 PJ. There is potential to increase the amount of crop residues to 238 PJ through measures such as no till cultivation and adopting improved cropping systems. These estimates were based on minimum residues requirements of 2 t ha −1 for soil erosion control and additional residue amounts to maintain 2% SOC level. At the farm gate, crop residues cost between 0.9 and 1.7 $ GJ −1 . About 96% of these residues are available below 1.5 $ GJ −1 . In the improved scenario, up to 85% of the biomass is below 1.3 $ GJ −1 . For biomass deliveries at the conversion plant, about 36% is below 5 $ GJ −1 while in the optimised scenario, about 87% is delivered below 5$ GJ −1 . Co-firing residues with coal results in lower cost of electricity compared to other renewables and significant GHG (CO 2 eq) emissions reduction (up to 0.72 tons MWh −1 ). Establishing sustainable crop residue supply systems in South Africa could start by utilising the existing agricultural infrastructure to secure supply and develop a functional market. It would then be necessary to incentivise improvements across the value chain. [ABSTRACT FROM AUTHOR]

The expansion of the ethanol industry in Brazil faces two important challenges: to reduce total ethanol production costs and to limit the greenhouse gas (GHG) emission intensity of the ethanol produced. The objective of this study is to economically optimize the scale and location of ethanol production plants given the expected expansion of biomass supply regions. A linear optimization model is utilized to determine the optimal location and scale of sugarcane and eucalyptus industrial processing plants given the projected spatial distribution of the expansion of biomass production in the state of Goiás between 2012 and 2030. Three expansion approaches evaluated the impact on ethanol production costs of expanding an existing industry in one time step (one-step), or multiple time steps (multi-step), or constructing a newly emerging ethanol industry in Goiás (greenfield). In addition, the GHG emission intensity of the optimized ethanol supply chains are calculated. Under the three expansion approaches, the total ethanol production costs of sugarcane ethanol decrease from 894 US$/m 3 ethanol in 2015 to 752, 715, and 710 US$/m 3 ethanol in 2030 for the multi-step, one step and greenfield expansion respectively. For eucalyptus, ethanol production costs decrease from 635 US$/m 3 in 2015 to 560 and 543 US$/m 3 in 2030 for the multi-step and one-step approach. A general trend is the use of large scale industrial processing plants, especially towards 2030 due to increased biomass supply. We conclude that a system-wide optimization as a marginal impact on overall production costs. Utilizing all the predefined sugarcane and eucalyptus supply regions up to 2030, the results showed that on average the GHG emission intensity of sugarcane cultivation and processing is −80 kg CO 2 /m 3 , while eucalyptus GHG emission intensity is 1290 kg CO 2 /m 3 . This is due to the high proportion of forest land that is expected to be converted to eucalyptus plantations. Future optimization studies may address further economic or GHG emission improvement potential by optimizing the GHG emission intensity or perform a multi-objective optimization procedure. [ABSTRACT FROM AUTHOR]

This paper presents an economic outlook of the ethanol industry in Brazil considering different biomass feedstocks and different industrial processing options. A spreadsheet model was designed to account for different feedstocks and industrial processes, and expected trends in biomass yield, sugar- and fibre content, industrial scale and efficiency. Sugarcane and energycane cultivation costs may be reduced from 35 US$ 2010 /TC in 2010 to 27 US$ 2010 /TC and 22 US$ 2010 /TC in 2030 respectively. Eucalyptus and elephant grass cultivation costs could be reduced from 32 to 23 US$ 2010 /tonne wet and 38 to 26 US$ 2010 /tonne wet for eucalyptus and elephant grass. Total ethanol production costs of first generation processing may decrease from 700 US$ 2010 /m 3 in 2010, to 432 US$ 2010 /m 3 in 2030. First generation ethanol production costs may decrease by reduced feedstock costs, increase in sugar content, utilization of cane trash, and use of sweet sorghum. Furthermore, the improvement in industrial efficiency of the first generation process, increasing industrial scale and change to an improved technology are other measures. For second generation technology utilizing eucalyptus, the total ethanol production costs could be strongly reduced to 424 US$ 2010 /m 3 in 2030. Costs reduction measures for second generation industrial processing include reduced feedstock costs, increasing industrial efficiency and scale, and a change to more advanced industrial process. Overall, biomass yield, increase in sugar content of sugarcane, and improved industrial efficiency are important parameters in total ethanol production costs. Ongoing RD&D effort and commercialization of second generation industrial processing may result in the lowest ethanol production costs for second generation processing in the future. [ABSTRACT FROM AUTHOR]