Stakeholder opinion on constrained 2030 bioenergy scenarios for North West England

English farmers are subsidised by the UK government to plant (short rotation coppice—SRC) willow as an energy crop. This study incorporates the outputs of techno-economic and environmental life cycle assessment modelling of bioenergy power and combined heat and power (CHP) plants within a simple spreadsheet model that enables users to partially modify bioenergy scenarios for SRC willow. The model is intended as an opinion-elicitation device. It is restricted in scope, reflecting the electrical power emphasis of the first phase of the Supergen Biomass and Bioenergy research programme. Bioenergy policy stakeholders in North West (NW) England were asked to use the model to develop 2030 scenarios for SRC willow fuelling eight types of bioenergy power and CHP plant. Users allocate finite land inputs to the different power and CHP plant types and the sheet outputs the energy supply, environmental and agricultural employment implications. Policy stakeholders are shown to hold widely differing views of how the bioenergy heat and power sector might and should look in 2030. If the policy stakeholders’ 2030 scenarios prove accurate, the percentage of regional households likely to be electrically supplied by willow coppice grown in NW England will be small, at some 3.6%.     

Identifying potential environmental impacts of large-scale deployment of dedicated bioenergy crops in the UK

There is momentum, globally, to increase the use of plant biomass for the production of heat, power and liquid transport fuels. This review assesses the evidence base for potential impacts of large-scale bioenergy crop deployment principally within the UK context, but with wider implications for Europe, the USA and elsewhere. We focus on second generation, dedicated lignocellulosic crops, but where appropriate draw comparison with current first-generation oil and starch crops, often primarily grown for food.For lignocellulosic crops, positive effects on soil properties, biodiversity, energy balance, greenhouse gas (GHG) mitigation, carbon footprint and visual impact are likely, when growth is compared to arable crops. Compared to replacement of set-aside and permanent unimproved grassland, benefits are less apparent. For hydrology, strict guidelines on catchment management must be enforced to ensure detrimental effects do not occur to hydrological resources. The threat of climate change suggests that action will be required to ensure new genotypes are available with high water use efficiency and that catchment-scale management is in place to secure these resources in future. In general, for environmental impacts, less is known about the consequences of large-scale deployment of the C4 grass Miscanthus, compared to short rotation coppice (SRC) willow and poplar, including effects on biodiversity and hydrology and this requires further research.Detailed consideration of GHG mitigation and energy balance for both crop growth and utilization suggest that perennial crops are favoured over annual crops, where energy balances may be poor. Similarly, crops for heat and power generation, especially combined heat and power (CHP), are favoured over the production of liquid biofuels. However, it is recognized that in contrast to heat and power, few alternatives exist for liquid transportation fuels at present and research to improve the efficiency and energy balance of liquid transport fuel production from lignocellulosic sources is a high current priority.Although SRC, and to a lesser extent energy grasses such as Miscanthus, may offer significant benefits for the environment, this potential will only be realized if landscape-scale issues are effectively managed and the whole chain of crop growth and utilization is placed within a regulatory framework where sustainability is a central driver. Land resource in the UK and throughout Europe will limit the contribution that crops can make to biofuel and other renewable targets, providing a strong driver to consider sustainability in a global context.     

Large-scale bioenergy production from soybeans and switchgrass in Argentina: Part B. Environmental and socio-economic impacts on a regional level

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 1.2 ton C/ha/year and for soybean from ?1.2 to 0 ton C/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 2–10 ton/ha for the soybean bioenergy chain and 1–2 ton/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.     

Does bio-oil derived from logging residues in Finland meet the European Union greenhouse gas performance criteria?

The renewable energy directive (RED) of the EU sets mandatory targets for increasing the use of renewable energy in EU member states by 2020. The RED introduces sustainability criteria for transportation biofuels and other bioliquids in order to ensure that their increasing production does not cause serious environmental and social problems. Bio-oil production through fast pyrolysis is one technology under development. The aim of this paper is to explore whether bio-oil derived from logging residues in Finland meets the GHG performance criteria set by the EU. The pyrolysis reactor is assumed to be integrated with a combined heat and power production plant (CHP). Special attention is paid to uncertainty analysis. An emission reduction target of 60% as compared to the reference fuel is exceeded if the pyrolysis reactor and the CHP plant are considered as separate units, and changes in soil carbon balances are ignored. On the contrary, the particular target is not met using a 20-year time frame for changes in soil carbon balances. The results depend in large measure on the selection of parameters set and the interpretation of the definitions provided in the RED to set the system boundary for the pyrolysis reactor and the CHP plant.     

Direct and indirect land use changes issues in European sustainability initiatives: State-of-the-art, open issues and future developments

Facing climate change and growing energy prices, the use of bioenergy is continuously increasing in order to diminish greenhouse gas emissions, secure energy supply and create employment in rural areas. Because the production of biomass or biofuels, wherever it takes place, comes along with externalities, positive or negative, the need for biomass and bioenergy sustainability criteria is more than ever felt. Research on sustainability criteria and certification systems has started through several national and international initiatives. Considering the benefits of an increased use of bioenergy but also the urge for limiting potential negative environmental and socio-economic impacts, the aim of these initiatives was to make the first move regarding bioenergy sustainability, while waiting for the European legislation to regulate this crucial issue. Land use changes, whether direct or indirect, are one of the most important consequences of bioenergy production. While direct land use changes are more easily assessed locally, indirect land use changes exceed the company level and need to be considered at a global scale. Methodologies for dealing with direct and indirect land use changes are proposed among others in the European, Dutch, British and German sustainability initiatives. This paper aims at presenting and comparing those four European initiatives, with a focus on their propositions for direct and indirect land use changes assessment. Key issues are discussed and recommendations are made for steps to overcome identified difficulties in accurately assessing the effects of indirect land use change due to bioenergy production.     

Sustainability impact assessment for local energy supplies' development – The case of the alpine area of Lake Como,Italy

The development of distributed energy systems has important environmental, social and economic implications. Local decision-making processes must be guided by a careful evaluation of the sustainability of production chains and alternative choices. The aim of this study is to explore if and how an integrated assessment can quantify the extent to which bioenergy supply chain development contributes to rural development and energy policy objectives. We applied a Sustainability Impact Assessment (SIA) for local bioenergy development in the alpine area of Lake Como (Italy). We modeled the local bioenergy chain in 2008 and eleven scenarios considering different biomass utilizations, mechanization levels, combustion technologies, and subsidies schemes at 2020. We calculated economic, social and environmental indicators. We interpret and discuss the scenario analysis in order to support the bioenergy planning under the light of its implications for the different policy aims and concerns.     

Sustainability assessment of wood-based bioenergy – A methodological framework and a case-study

The sustainability of the utilization of wood biomass for energy and other purposes has been widely assessed in different studies. Especially discrete methods from the family of Multi-Criteria Decision Analysis (MCDA), such as Outranking methods, Multi-Attribute Utility Theory, and Analytic Hierarchy Process (AHP) are often applied. AHP is considered one of the most promising options to be used in sustainability assessments, because it is comprehensible to apply and it incorporates the preferences of decision-makers in an advanced manner. In this study, we present a theoretical multi-dimensional framework based on a modified version of AHP for assessing sustainability and apply it in a case of wood-based bioenergy production in eastern Finland. The framework includes four dimensions of sustainability and life cycle phases from the acquisition of raw material to manufacturing the final product. The production systems used in the empirical sustainability assessments are a local heat production plant, a combined heat and power production plant, and a wood pellet processing plant. Local sustainability experts identified indicators relevant at the regional scale. The impact assessment data were obtained from literature, by interviewing the managers of the bioenergy plants, and from a postal survey administered to local people. The local heat provider received the highest sustainability index; however, there were no considerable differences between the sustainability indexes. None of the bioenergy production systems can be considered the most sustainable regardless of the assumptions employed in the framework. The framework provided the basis for a quantitative, interdisciplinary approach to assess sustainability.     

Decentralised bioenergy systems: A review of opportunities and threats

Decentralised bioenergy systems are receiving increasing attention due to the potential ability to support local development, create local employment, and contribute to climate change mitigation. These issues, along with other bioenergy sustainability issues, are reviewed through eighteen international case studies with the objective of identifying opportunities and threats to decentralised bioenergy systems. The case studies were selected based on feedstock type, bioenergy type, production capacity, synergistic alliances, ownership structure and physical locations. This variation was used to provide a basis for evaluating opportunities and threats from different contexts. Commercial viability remains the primary concern for the sustainability of decentralised bioenergy systems. There are, however, opportunities for compounding benefits through integrating small scale decentralised bioenergy systems with other production systems. Integrated production, including closed loop models, allow waste materials from one process to be used as inputs in other production processes, and thereby increasing economic, social and environmental outcomes. Synergistic opportunities along the bioenergy production chain, which include feedstock production, bioenergy marketing and distribution could also be exploited by communities and other investors to minimise decentralised production risk.     

The future of bioenergy and rural development policies in Africa and Asia

This special issue has presented some of the specific findings of the RE-Impact Project which was commissioned and funded by the EuropeAid Cooperation Office from 2007 until its conclusion in 2010. The project aimed to provide impact assessment frameworks and influence relevant policies through direct involvement in bioenergy projects and policy analysis in South Africa, Uganda, India and China. The papers summarised here have covered issues related to Jatropha curcas and forest-based bioenergy in these countries. Taking an overall look at the project findings we can identify a number of general conclusions relevant for the future of bioenergy and rural development in Africa and Asia. First, only local and context-specific sustainability assessment can identify the risk and responsibilities of the different groups and the exact impact on the environment. Second, many initiatives both in biofuels and forest-based bioenergy are marred by a lack of understanding of the life-cycle financial analysis. Third, careful consideration of local physical and social conditions and the economics of the production chain can identify real opportunities for rural development using bioenergy. The current global impasse in bioenergy policies could actually be advantageous to the development of bioenergy in developing countries. Without the pressure from America and Europe to develop bioenergy systems for climate change mitigation, countries in Africa and Asia may have the breathing room to shape bioenergy systems for their own internal energy supply in an orderly fashion. However, in order to avoid environmental and social impacts it will be necessary to articulate together elements of a number of measures including market-based certification, national policy formulation, national legislation, impact assessments, sustainability planning, land use planning, research, monitoring and evaluation taking into account country and project specific sustainability criteria. Unfortunately, many of the countries in Africa and Asia where bioenergy can play an important role still lack institutional structures able to articulate this sustainable development.     

Quantification of employment from biomass power plants

One of the attractions of developing bioenergy systems is the potential for job creation and economic development of rural economies. This paper seeks to quantify the expected employment impacts of individual bioenergy developments. The assessment includes agricultural labour growing energy crops for SRC and miscanthus options, transport and processing of the feedstock, staffing at the thermal conversion plant, employment within the equipment supply chain and the induced employment impact. Power only bioenergy systems are shown to typically create 1.27 man years of employment per GWh electricity produced, regardless of technology or scale of implementation. CHP systems can create more than 2 man years of employment per GWh electricity produced, although most of this enhanced economic impact can be attributed to the fact that a comparative analysis per unit of electricity produced ignores the heat output of the system.     

Recent developments of biofuels/bioenergy sustainability certification: A global overview

The objective of this paper is to provide a review on the latest developments on the main initiatives and approaches for the sustainability certification for biofuels and/or bioenergy. A large number of national and international initiatives lately experienced rapid development in the view of the biofuels and bioenergy targets announced in the European Union, United States and other countries worldwide. The main certification initiatives are analysed in detail, including certification schemes for crops used as feedstock for biofuels, the various initiatives in the European Union, United States and globally, to cover biofuels and/or biofuels production and use. Finally, the possible way forward for biofuel certification is discussed. Certification has the potential to influence positively direct environmental and social impact of bioenergy production. Key recommendations to ensure sustainability of biofuels/bioenergy through certification include the need of an international approach and further harmonisation, combined with additional measures for global monitoring and control. The effects of biofuels/bioenergy production on indirect land use change (ILUC) is still very uncertain; addressing the unwanted ILUC requires sustainable land use planning and adequate monitoring tools such as remote sensing, regardless of the end-use of the product.     

Biomass from agriculture in small-scale combined heat and power plants - A comparative life cycle assessment

Biomass produced on farm land is a renewable fuel that can prove suitable for small-scale combined heat and power (CHP) plants in rural areas. However, it can still be questioned if biomass-based energy generation is a good environmental choice with regards to the impact on greenhouse gas emissions, and if there are negative consequences of using of agricultural land for other purposes than food production.In this study, a simplified life cycle assessment (LCA) was conducted over four scenarios for supply of the entire demand of power and heat of a rural village. Three of the scenarios are based on utilization of biomass in 100 kW (e) combined heat and power (CHP) systems and the fourth is based on fossil fuel in a large-scale plant. The biomass systems analyzed were based on 1) biogas production with ley as substrate and the biogas combusted in a microturbine, 2) gasification of willow chips and the product gas combusted in an IC-engine and 3) combustion of willow chips for a Stirling engine. The two first scenarios also require a straw boiler.The results show that the biomass-based scenarios reduce greenhouse gas emissions considerably compared to the scenario based on fossil fuel, but have higher acidifying emissions. Scenario 1 has by far the best performance with respect to global warming potential and the advantage of utilizing a byproduct and thus not occupying extra land. Scenario 2 and 3 require less primary energy and less fossil energy input than 1, but set-aside land for willow production must be available. The low electric efficiency of scenario 3 makes it an unsuitable option.     

Identifying environmentally and economically optimal bioenergy plant sizes and locations: A spatial model of wood-based SNG value chains

The optimal size and location of bioenergy plants with regards to environmental and economic performance are assessed with a spatially explicit value chain model of the production of synthetic natural gas (SNG) from wood. It consists of several individual models for the availability, harvest, transportation, conversion of wood to SNG, electricity and heat, and the use of these products to substitute non-renewable energy services. An optimization strategy is used to choose the optimal technology configuration for plant sizes from 5 to 200 MW and different locations for any desired weighting between the environmental performance based on life cycle assessment (LCA) and the economic performance.While the economic optima are found at plant sizes between 100 and 200 MW, the environmental optima are found in the range of 5–40 MW. This trade-off can be minimized at plant sizes above 25 MW according to the presented model. The most important driver of the environmental performance is the efficient substitution of non-renewable energy, which is a site-specific factor. In comparison to this, spatial factors such as wood availability, harvest, and transportation, have a smaller influence on the environmental performance, at least for a country of the size of Switzerland. The main drivers of the economic performance are the revenues from the sale of the SNG plant's products and the SNG production costs, but transportation and wood costs also play a role.     

Indicators of bioenergy-related certification schemes – An analysis of the quality and comprehensiveness for assessing local/regional environmental impacts

Bioenergy is receiving increasing attention because it may reduce greenhouse gas emissions, secure and diversify energy supplies and stimulate rural development. The environmental sustainability of bioenergy production systems is often determined through life-cycle assessments that focus on global environmental effects, such as the emission of greenhouse gases or air pollutants. Local/regional environmental impacts, e.g., the impacts on soil or on biodiversity, require site-specific and flexible options for the assessment of environmental sustainability, such as the criteria and indicators used in bioenergy certification schemes.In this study, we compared certification schemes and assessed the indicator quality through the environmental impact categories, using a standardized rating scale to evaluate the indicators. Current certification schemes have limitations in their representation of the environmental systems affected by feedstock production. For example, these schemes predominantly use feasible causal indicators, instead of more reliable but less feasible effect indicators. Furthermore, the comprehensiveness of the depicted environmental systems and the causal links between human land use activities and biophysical processes in these systems have been assessed. Bioenergy certification schemes seem to demonstrate compliance with underlying legislation, such as the EU Renewable Energy Directive, rather than ensure environmental sustainability. Beyond, certification schemes often lack a methodology or thresholds for sustainable biomass use. Lacking thresholds, imprecise causal links and incomplete indicator sets may hamper comparisons of the environmental performances of different feedstocks. To enhance existing certification schemes, we propose combining the strengths of several certification schemes with research-based indicators, to increase the reliability of environmental assessments.     

Towards integrated sustainability assessment for energetic use of biomass: A state of the art evaluation of assessment tools

Biomass is expected to play an increasingly significant role in the ‘greening’ of energy supply. Nevertheless, concerns are rising about the sustainability of large-scale energy crop production. Impacts must be assessed carefully before deciding whether and how this industry should be developed, and what technologies, policies and investment strategies should be pursued. There is need for a comprehensive and reliable sustainability assessment tool to evaluate the environmental, social and economic performance of biomass energy production. This paper paves the way for such a tool by analysing and comparing the performance and applicability of a selection of existing tools that are potentially useful for sustainability assessment of bioenergy systems. The selected tools are: Criteria And Indicators (C&I), Life Cycle Assessment (LCA), Environmental Impact Assessment (EIA), Cost Benefit Analysis (CBA), Exergy Analysis (EA) and System Perturbation Analysis (SPA). To evaluate the tools, a framework was constructed that consists of four evaluation levels: sustainability issues, tool attributes, model structure, area of application. The tools were then evaluated using literature data and with the help of a Delphi panel of experts. Finally, a statistical analysis was performed on the resulting data matrix to detect significant differences between tools. It becomes clear that none of the selected tools is able to perform a comprehensive sustainability assessment of bioenergy systems. Every tool has its particular advantages and disadvantages, which means that trade-offs are inevitable and a balance must be found between scientific accuracy and pragmatic decision making. A good definition of the assessment objective is therefore crucial. It seems an interesting option to create a toolbox that combines procedural parts of C&I and EIA, supplemented with calculation algorithms of LCA and CBA for respectively environmental and economic sustainability indicators. Nevertheless, this would require a more comprehensive interdisciplinary approach to align the different tool characteristics and focuses.     

LCA of poplar bioenergy system compared with Brassica carinata energy crop and natural gas in regional scenario

The poplar bioenergy system has been analysed applying life cycle assessment (LCA) to compare its environmental performance to: Ethiopian mustard bioenergy system and natural gas. The life cycle impact assessment (LCIA) shows that the use of fertilizers is the highest impact in four of the 10 environmental categories, representing between 39% and 67% of the impact in them. The diesel used in transport vehicles and agricultural tractors also has a significant impact in another five of the 10 analysed categories 40–85%. The poplar bioenergy system contributes to global warming with 1.90–1.98 g CO₂ eq MJ^?1 biomass produced. The production and transport as far as the thermoelectric plant of the poplar biomass consumes 0.02 MJ of primary energy per 1 MJ of biomass stored. In comparison with Ethiopian mustard and natural gas, it reduces primary energy consumption by 83% and 89% and the greenhouse gas emission by 84% and 89%, respectively. The results of the analysis support that the poplar bioenergy system is viable from an energy balance and environmental perspective for producing energy in southern Europe, as long as it is cultivated in areas where water is available. This latter point and the better environmental performance of both crops in comparison to natural gas allows us to affirm that the combination of several crops adapted to the local agro-climatic conditions of the territory will be the most suitable strategy in Mediterranean areas that wish to reach the global energy production targets in terms of biomass established by the European Union (EU).     

Technical and operational performance of a small-scale comined heat-and-power (CHP) plant

This paper deals with the technical, economic and environmental performance of a 40 kWe CHP plant, located within the Queens Building at De Montfort University. Conventional analysis gives the overall efficiency as 77% with a 7.1 year payback period. By examining the thermal and casual gains, a novel alternative analysis gives an effective plant efficiency of 104%. Environmental analysis shows that the CHP-generated energy produces half the carbon dioxide emissions of separately imported electricity and heat from a boiler plant. The scheduling of plant utilisation has an effect on thermal efficiency due to thermal capacitance. The economic and environmental benefits of small-scale CHP plants are demonstrated.     

Sustainable ethanol production from lignocellulosic biomass - Application of exergy analysis

The sustainability of the second-generation biofuels requests to confirm that the energy produced from lignocellulosic biomass is significantly greater than the energy consumed in the process. As lignocellulosic biomass does not affect the food supply, sugarcane bagasse was analyzed as a raw material for second-generation biofuels production. Exergy analysis serves as a unified and effective tool to evaluate the global process efficiency. Exergy analysis evaluates the performance of sugarcane bagasse and its sustainability in the bioethanol production process. In this work, four ethanol production topologies using the typical daily amount of residual biomass produced by the sugar industry were compared. The exergy analysis concept is effective in screening design alternatives with the lowest environmental impact for second-generation bioethanol fuel production from renewable resources. This study was executed by the use of the Aspen Plus^® program and other software developed by the authors.     

Growing trade of bioenergy in the EU: Public acceptability, policy harmonization, European standards and certification needs

Since 2000, the consumption of bioenergy in the European Union has grown, along with a concurrent growth in the trade of biomass for energy purposes (though traded volumes still remain small). Bioenergy production and trade will likely continue to increase into the future, driven by climate change concerns, emissions reduction targets, increasing concerns about domestic energy security and favourable policies. The harmonization of European standards and the development of certification systems are key issues to resolving potential negative effects of increased biomass trade. Certification systems not only address the issue of environmental sustainability from production to end-use, but also allow for product differentiation while adding value to sustainably produced products, which can ultimately enhance a competitive and sustainable bioenergy market. In addition to analyzing bioenergy trade growth in the European Union, a questionnaire survey of 92 bioenergy experts from eight member states within the European Union was conducted. Survey results show that bioenergy is highly accepted in the European Union but that there is a lack of European standards and policy harmonization, along with the absence of a competitive market or a certification system, all of which are necessary for sustainable production and trade of bioenergy. A large majority (63 percent) of the total respondents agreed that the certification of bioenergy is necessary to promote the sustainable use of biomass.     

Modelling sustainable bioenergy potentials from agriculture for Germany and Eastern European countries

This paper presents a model for analyzing the sustainable potential of agricultural biomass for energy production. Available land and residue potentials are assessed up to 2030 for Germany, Poland, the Czech Republic and Hungary. Two scenarios are presented: a “business as usual” scenario is compared to a sustainability scenario. The latter implements a comprehensive sustainability strategy, taking also into account non-agricultural land use such as building activity and nature conservation. On the one hand our model quantifies the conflict of objectives between enhanced extensification in agriculture and increased area for nature conservation. On the other hand the synergies in restricting built up area and increased mobilisation of agricultural residues are assessed. Additionally the impact of reduced subsidized agricultural exports from the EU is calculated, also as an indicator for the influence of world food markets on bioenergy potentials.Our results show that the sustainable energy potential from agricultural biomass is strongly restricted for Germany and the Czech Republic compared to their energy demand. But in Poland and Hungary native agricultural biomass provides a much higher potential for energy supply, even if sustainability is comprehensively considered. However, this is strongly influenced by the amount of agricultural exports of each country. For bioenergy from agricultural cultivation to remain a sustainable option in the energy sector, its influence on the food markets must be respected more thoroughly and a comprehensive approach to sustainable development in land use is a prerequisite.