Bioenergy Production Chains Research Articles

Sustainability Impact Assessment of Forest Bioenergy Value Chains in Quebec (Canada)—A ToSIA Approach

Forest bioenergy value chains can offer attractive opportunities to promote economic development and mitigate climate change. However, implementing profitable and efficient forest biomass value chains requires overcoming barriers that continue to hinder the development of bioenergy systems in several jurisdictions. The objective of this study was to compare the economic, social, and environmental sustainability of various potential configurations of forest bioenergy value chains, including forest biomass supply and bioenergy production chains, in the Capitale-Nationale region of Quebec (Canada), which is a jurisdiction that has considerable forest resources but makes little use of bioenergy. We based our study on the ToSIA model parameterization and compared various policy measures, biomass supply, and logistics scenarios for 2008 and 2030. Our results showed that wood chip and pellet value chains in the Capitale-Nationale region would positively contribute to the regional economy in 2030, even in the absence of subsidies. Moreover, actions to increase biomass feedstock mobilization in 2030 would lead to an increase in gross value added, employment, and energy production in the region compared with 2008 and a greater increase than other considered policy or logistical measures. However, increased biomass feedstock mobilization would also mean higher relative GHG emissions and more fossil fuel energy input per unit of bioenergy than in the other scenarios. Conversely, optimizing biomass feedstock and combustion technologies could help minimize the fossil fuel energy input needed and GHG and some non-GHG pollutant emissions. Overall, our study suggested that implementing policy and logistical measures for forest biomass value chains could make the significant mobilization of forest bioenergy attainable and, in turn, Quebec’s 2030 bioenergy target of 17 petajoules realistic.

Landowners’ willingness to promote bioenergy production on wasteland − future impact on land use of cutaway peatlands

Landowners are the key players in bioenergy production on wasteland; such as cutaway peatlands. In this study, the landowner’s interest to use cutaway peatlands for bioenergy production was investigated using a survey and GIS (Geographic Information Systems) methods in an area in South Ostrobothnia, Finland. The focus was to identify which different bioenergy production chains are preferred by the respondents: combustion, gasification or biogas production from agriculture, energy-willow short-rotation forestry or forestry based energy crops. Also, the influence of personal environmental values on the selection was measured and the future impacts and barriers for the land use were assessed.Afforestation was the most popular after-use method among the landowners. The next most favorable method was energy crop cultivation but it was highly dependent on economic profitability and subsidies. Currently, approximately 8.2% or 500ha of the total peat extraction area could be used for bioenergy production in the region by 2035. Based on the survey, forest based biomass is the best option if bioenergy is to be produced. The next choice was agro biomass and the least favored plant was willow. This study suggests that the biggest cutaway peatlands will be converted to forest energy in the future. Suggestive results were that the owners with high environmental values are especially interested in agro biomass growing and the landowner having a distant home place does not have a negative influence on bioenergy production. Altogether, land use and biomass production of cutaway peatlands is connected with the demands of the Finnish bio-economy.

Comparative environmental and energy profiles of potential bioenergy production chains in Southern Europe

Abstract In this study, life cycle assessment (LCA) is used to assess and compare the environmental and energy profiles of three potential bioenergy production chains using different available feedstocks in Southern European countries. Two wastes, vineyard pruning and eucalypt logging residues, and a wooden energy crop, poplar, were examined in detail. The comparative LCA study showed that the use of poplar biomass for bioenergy production has a greater impact than the use of vineyard pruning and logging residues. The contribution from the poplar-cultivation-related activities considerably affected the results, as all the activities from field preparation to harvesting have been included within the system boundaries. In contrast, all the activities performed in the vineyard and forest prior to collection of the residues have not been computed in both scenarios since they have been allocated to the driving force of these stands: grapes and roundwood, respectively. The results support the idea that forest and agricultural waste would be an interesting and potential raw material for bioenergy purposes. However, further analysis should focus on these potential bioenergy sources, namely in terms of their availability and technical burning conditions, in order to meet energy requirements. Moreover, the environmental results were compared with others from literature corresponding to electricity production using alternative biomass sources and fossil fuels. In all the categories considered for comparison, environmental benefits were reported for the electricity production using a biomass source. However, these results must be carefully used since other issues – such as production costs, water availability and land use – should be considered.

Evaluation of the Effect of Agricultural Management on Energy Yield and Greenhouse Gas Emission Reduction of Bioenergy Production Chains

The role of energy crops in reducing fossil energy use and greenhouse gas emission is much debated. To improve decision making on the use of crops for producing bioenergy, a tool (Energy Crop Simulation Model or E-CROP) has been developed to calculate 1) sustainable crop dry matter yield levels as function of agricultural inputs, and 2) gross and net energy yield and greenhouse gas emission reduction, covering the entire bioenergy production chain from sowing to distribution of bioenergy. E-CROP can be applied to a wide range of crops, soils, climatic conditions, management choices, and conversion technologies. This paper describes E-CROP and focuses on its application on four arable crops, as cultivated on two contrasting sites in the Netherlands (potato and sugar beet for bioethanol, winter oilseed rape for biodiesel and silage maize for bioelectricity) and on the effect of crop management (viz. irrigation and nitrogen fertilisation). In all situations, gross energy output exceeded total energy input. Calculated for an average situation, net energy yield ranged from 45 to 140 GJ.ha-1. Lowering irrigation and/or fertilisation input levels generally resulted in a reduction of net energy yields. The net reduction of greenhouse gas emissions in the average situation ranged from 0.60 to 6.5 t CO2-eq.ha-1. In general, N2O emission from nitrogen fertiliser caused large variations in the net reduction of greenhouse gas emission, which even became negative in some situations. Lowering nitrogen fertilisation to levels that are suboptimal for net energy yields enhanced the net reduction in greenhouse gas emission, implicating that both goals cannot be optimised simultaneously. Agricultural knowledge is important for optimising the outputs of bioenergy production chains.

Residues of bioenergy production chains as soil amendments: Immediate and temporal phytotoxicity

The current shift towards bioenergy production increases streams of bioenergy rest-products (RPs), which are likely to end-up as soil amendments. However, their impact on soil remains unclear. In this study we evaluated crop phytotoxicity of 15 RPs from common bioenergy chains (biogas, biodiesel, bioethanol and pyrolysis). The RPs were mixed into a sandy soil and the seedling root and shoot elongation of lettuce (Lactuca sativa L.), radish (Raphanus sativus L.), and wheat (Triticum aestivum L.) were measured. Immediate phytotoxic effects were observed with biodiesel and bioethanol RPs (root elongation reduced to 14–60% for the three crops; P<0.05). However, phytotoxicity was no longer significant after seven days. Digestates had no phytotoxic effect whereas biochars ranged from beneficial to detrimental depending on the original feedstock and temperature of pyrolysis. Biochar amendment alleviated phytotoxicity of bioethanol by-products for wheat and radish. Phytotoxicity assessment is critical for successful soil amendment with bioenergy RPs.

Sustainability impact assessment of increasing resource use intensity in forest bioenergy production chains

Changing forest management practices towards more intensive biomass utilization for energy purposes will affect the sustainability of resource management. The Tool for Sustainability Impact Assessment was applied to evaluate the environmental, social, and economic sustainability impacts of the stepwise increased extraction of forest biomass of three typical Scandinavian Scots pine bioenergy production chains (BPCs). The assessed sources of the woody biomass were pellets as a by-product of the sawmilling industry, wood chips deriving from early whole-tree harvesting, and residues from final cuttings. Three commercially practiced BPCs were compared. By the additional extraction of biomass for heat production, the employment increased by 0.6 person-years 1000 m ―3 solid wood chips, while there was a decrease in the costs and greenhouse gases emitted per unit of heat consumed. Furthermore this practice did not only add positive socio-economic but also positive environmental impacts on sustainability, particularly on the greenhouse gas balance and the energy efficiency ratio (input to output ratio along the BPC), which was determined to be 1-24. Potential drawbacks, on the other hand, include decreasing nutrient returns to the soil and the associated potential reduction in future stand productivity. Fertilization might be needed to maintain sustainable forest growth on poor sites.

The effect of spatial variables on the economic and environmental performance of bioenergy production chains

The aim of this paper is to understand the impacts of spatial variables on the performance of bioenergy production chains (BPCs). Even though the strong debates continue on the use of first generation biomass for bioenergy production, many countries continue to utilize it as an alternative energy source. Several studies have been carried out on biomass transformation efficiency, on environmental impacts of using crop in biofuel production, and on its negative effects on increasing food prices. However, less attention has been paid to the role played by the spatial variables on the performance measures of BPCs. In this paper, we analyse how three spatial variables, i.e. cultivation area size, land dispersion, and accessibility to cultivation areas, can affect the performance of energy-balanced BPC, which produces its own electric and thermal energy demand. The chain is represented as a network of processes, where all inputs and outputs are geographically referred and analysed in a theoretical case example. We propose an enterprise input–output (EIO) model, which can be used as an accounting tool to compute the main materials and energy flows-related costs and as a planning tool to evaluate the chain performance in different scenarios. Finally, the proposed model is applied to an actual case study, to investigate the opportunity to establish a sunflower-based BPC in Apulia region (Italy) and to assess its performance. Results show that higher land dispersion degree and less area accessibility levels reduce the economic and environmental performance of the BPCs. The construction of the energy-balanced chain reduces the negative environmental impacts caused by fossil energy use in the processes of the BPC. Managerial implications can also be obtained from actual case study about the biodiesel plant location decisions.

Bioenergy by‐products as soil amendments? Implications for carbon sequestration and greenhouse gas emissions

AbstractAn important but little understood aspect of bioenergy production is its overall impact on soil carbon (C) and nitrogen (N) cycling. Increased energy production from biomass will inevitably lead to higher input of its by‐products to the soil as amendments or fertilizers. However, it is still unclear how these by‐products will influence microbial transformation processes in soil, and thereby its greenhouse gas (GHG) balance and organic C stocks. In this study, we assess C and N dynamics and GHG emissions following application of different bioenergy by‐products to soil. Ten by‐products were selected from different bioenergy chains: anaerobic digestion (manure digestates), first generation biofuel by‐products (rapeseed meal, distilled dried grains with solubles), second‐generation biofuel by‐products (nonfermentables from hydrolysis of different lignocellulosic materials) and pyrolysis (biochars). These by‐products were added at a constant N rate (150 kg N ha−1) to a sandy soil and incubated at 20 °C. After 60 days, &gt;80% of applied C had been emitted as CO2 in the first‐generation biofuel residue treatments. For second‐generation biofuel residues this was approximately 60%, and for digestates 40%. Biochars were the most stable residues with the lowest CO2 loss (between 0.5% and 5.8% of total added C). Regarding N2O emissions, addition of first‐generation biofuel residues led to the highest total N2O emissions (between 2.5% and 6.0% of applied N). Second‐generation biofuel residues emitted between 1.0% and 2.0% of applied N, with the original feedstock material resulting in similar N2O emissions and higher C mineralization rates. Anaerobic digestates resulted in emissions &lt;1% of applied N. The two biochars used in this study decreased N2O emissions below background values. We conclude that GHG dynamics of by‐products after soil amendment cannot be ignored and should be part of the lifecycle analysis of the various bioenergy production chains.

ENVIRONMENTAL SCENARIOS FOR MANDATORY BIO-FUEL BLENDING TARGETS: AN APPLICATION OF INTUITIVE LOGICS &lt;br&gt;&lt;strong&gt;DOI:10.7444/fsrj.v2i1.23&lt;/strong&gt;

Os cenários para as metas de adição obrigatória de biocombustíveis são uma parte importante do planejamento estratégico das cadeias produtivas de alimentos e bioenergia, sendo o seu desenho o objetivo desse artigo. Cada cenário conta uma história de como os vários elementos poderiam interagir sob certas condições. O método usado aqui tem como base as contribuições anteriores de Schoemaker (1995) e Schwartz (1991). Uma seqüência de seis passos é seguida: i) identificar o foco de análise; ii) revisar as metas atuais de adição obrigatória; iii) identificar os direcionadores com base em uma analise macro-ambiental; iv) validar os direcionadores com especialistas; v) priorizar tais forças motrizes em termos de importância perante incertezas, construindo-se uma matriz de correlação; vi) desenhar os cenários. Ao final, são propostos três cenários alternativos relacionados à adoção, por parte de países, até 2020, de metas de adição obrigatória de biocombustíveis, que poderão orientar os tomadores de decisão dos mesmos durante o planejamento de sistemas de produção.

ENVIRONMENTAL SCENARIOS FOR MANDATORY BIO-FUEL BLENDING TARGETS: AN APPLICATION OF INTUITIVE LOGICS

Scenarios depicting targets concerning mandatory bio-fuel blending are critical to the strategic planning of food and bio-energy production chains and their design is the purpose of this paper. Each scenario tells a story about how various elements might interact under given conditions. The method herein utilized is primarily based on Schoemaker´s (1995) and Schwartz´s (1991) earlier proposals. A six step framework is followed: i) identify the focal issue; ii) summarize current mandatory blending targets; iii) identify the driving forces as of a macro-environmental analysis; iv) validate driving forces with specialists; v) rank such key forces by importance before uncertainties, building a correlation matrix; vi) design the scenarios. Finally, three alternative scenarios, relative to the adoption on behalf of countries, by the year 2020, of mandatory bio-fuel blending targets, are proposed which might guide these countries’ decision makers when planning production systems.

Estimating the pre-harvest greenhouse gas costs of energy crop production

Full greenhouse gas (GHG) life-cycle analysis of bio-energy production chains is often constrained by a lack of information on pre-harvest GHG costs and emissions during production of the energy crop. In this paper, we assessed pre-harvest GHG costs of production of short rotation coppice (SRC), Miscanthus and oil seed rape (OSR: for liquid bio-fuel production) when compared to a range of former land-use baselines. It was found that GHG costs are very low for Miscanthus and SRC but higher for OSR production, determined mainly by the need for nitrogen fertilisation. Compared to baseline land uses, SRC and Miscanthus have much lower GHG costs than arable cropping or intensively managed grasslands, with OSR production having similar GHG costs to arable cropping. Establishing broadleaved forests have low GHG costs, but 5-year GHG costs of Miscanthus and SRC are similar to forest. We show that former land use is of critical importance when determining if energy crops are a net source or sink of GHGs. Converting to SRC and Miscanthus are the most favourable energy crops in terms of GHG savings. Converting to OSR from arable cropping results in either small increases or decreases in GHG emissions, depending upon the former tillage practice on the arable land, but replacing either broadleaved woodland with OSR (mainly due to soil carbon loss and increased fertiliser-related N2O emissions), or grassland with OSR (mainly due to loss of soil carbon), greatly increases emissions. Policies to maximise GHG benefits from energy crops should encourage that they be established preferentially on croplands.