Using participatory system dynamics modelling to quantify indirect land use changes of biofuel projects

The use of biomass to produce biofuels can lead to both direct and indirect Land Use Change (LUC). While the causes underlying LUCs are complex their quantification is a scientific challenge that hinders decision-making. Here we demonstrate the application of participatory modelling in combination with System Dynamics techniques to the analysis of the land-change dynamics associated with biofuel supply chains. The ambition is to provide decision-makers with useful and credible knowledge of direct and indirect LUCs. We illustrate the application of the approach by applying it to a real‐world project for the production of advanced biofuels in Sardinia (Italy). The results show that the land use displacements vary in intensity and persistence depending on the crop management regime applied and the future development of the market of sheep cheese. The results were considered credible by actors with direct knowledge of the ‘real’ system and useful by decision makers

Energy balance and environmental impact analysis of marine microalgal biomass production for biodiesel generation in a photobioreactor pilot plant

A life cycle assessment (LCA) and an energy balance analysis of marine microalgal biomass production were conducted to determine the environmental impacts and the critical points of production for large scale planning. The artificial lighting and temperature conditions of an indoor bubble column photobioreactor (bcPBR) were compared to the natural conditions of an equivalent outdoor system. Marine microalgae, belonging to the dinoflagellate and raphidophyte groups, were cultured and the results were compared with published LCA data obtained from green microalgae (commonly freshwater algae). Among the species tested, Alexandrium minutum was chosen as the target marine microalgae for biomass production under outdoor conditions, although there were no substantial differences between any of the marine microalgae studied. Under indoor culture conditions, the total energy input for A. minutum was 923 MJ kg¯¹ vs. 139 MJ kg¯¹ for outdoor conditions. Therefore, a greater than 85% reduction in energy requirements was achieved using natural environmental conditions, demonstrating the feasibility of outdoor culture as an alternative method of bioenergy production from marine microalgae. The growth stage was identified as the principal source of energy consumption for all microalgae tested, due to the electricity requirements of the equipment, followed by the construction material of the bcPBR. The global warming category (GWP) was 6 times lower in outdoor than in indoor conditions. Although the energy balance was negative under both conditions, this study concludes with suggestions for improvements in the outdoor system that would allow upscaling of this biomass production technology for outdoor conditions in the Mediterranean

Life Cycle Assessment (LCA): informing the development of a Sustainable Circular Bioeconomy

The role of LCA in informing the development of a sustainable and circular bioeconomyis discussed. We analyse the critical challenges remaining in using LCA and propose improvements needed to resolve future development challenges. Biobased systems are often complex combinations of technologies and practices that are geographically dispersed overlong distances and with heterogeneous and uncertain sets of indicators and impacts. Recent studies have provided methodological suggestions on how LCA can be improved for evaluating the sustainability of biobased systems with a new focus on emerging systems, helping to identify environmental and social opportunities prior to large R&D investments. However, accessing economies of scale and improved conversion efficiencies whilst maintaining compatibility across broad ranges of sustainability indicators and public acceptability remain key challenges for the bioeconomy. LCA can inform, but not by itself resolve this complex dimension of sustainability. Future policy interventions that aim to promote the bioeconomy and support strategic value chains will benefit from the systematic use of LCA. However, the LCA community needs to develop the mechanisms and tools needed to generate agreement and coordinate the standards and incentives that will underpin a successful biobased transition. Systematic stakeholder engagement and the use of multidisciplinary analysis in combination with LCA are essential components of emergent LCA methods

Energy balance and environmental impact analysis of marine microalgal biomass production for biodiesel generation in a photobioreactor pilot plant

A life cycle assessment (LCA) and an energy balance analysis of marine microalgal biomass production were conducted to determine the environmental impacts and the critical points of production for large scale planning. The artificial lighting and temperature conditions of an indoor bubble column photobioreactor (bcPBR) were compared to the natural conditions of an equivalent outdoor system. Marine microalgae, belonging to the dinoflagellate and raphidophyte groups, were cultured and the results were compared with published LCA data obtained from green microalgae (commonly freshwater algae). Among the species tested, Alexandrium minutum was chosen as the target marine microalgae for biomass production under outdoor conditions, although there were no substantial differences between any of the marine microalgae studied. Under indoor culture conditions, the total energy input for A. minutum was 923 MJ kg¯¹ vs. 139 MJ kg¯¹ for outdoor conditions. Therefore, a greater than 85% reduction in energy requirements was achieved using natural environmental conditions, demonstrating the feasibility of outdoor culture as an alternative method of bioenergy production from marine microalgae. The growth stage was identified as the principal source of energy consumption for all microalgae tested, due to the electricity requirements of the equipment, followed by the construction material of the bcPBR. The global warming category (GWP) was 6 times lower in outdoor than in indoor conditions. Although the energy balance was negative under both conditions, this study concludes with suggestions for improvements in the outdoor system that would allow upscaling of this biomass production technology for outdoor conditions in the Mediterranean

Energy balance and environmental impact analysis of marine microalgal biomass production for biodiesel generation in a photobioreactor pilot plant

12 pages, 6 figures, 6 tablesA life cycle assessment (LCA) and an energy balance analysis of marine microalgal biomass production were conducted to determine the environmental impacts and the critical points of production for large scale planning. The artificial lighting and temperature conditions of an indoor bubble column photobioreactor (bcPBR) were compared to the natural conditions of an equivalent outdoor system. Marine microalgae, belonging to the dinoflagellate and raphidophyte groups, were cultured and the results were compared with published LCA data obtained from green microalgae (commonly freshwater algae). Among the species tested, Alexandrium minutum was chosen as the target marine microalgae for biomass production under outdoor conditions, although there were no substantial differences between any of the marine microalgae studied. Under indoor culture conditions, the total energy input for A. minutum was 923 MJ kg−1 vs. 139 MJ kg−1 for outdoor conditions. Therefore, a greater than 85% reduction in energy requirements was achieved using natural environmental conditions, demonstrating the feasibility of outdoor culture as an alternative method of bioenergy production from marine microalgae. The growth stage was identified as the principal source of energy consumption for all microalgae tested, due to the electricity requirements of the equipment, followed by the construction material of the bcPBR. The global warming category (GWP) was 6 times lower in outdoor than in indoor conditions. Although the energy balance was negative under both conditions, this study concludes with suggestions for improvements in the outdoor system that would allow up-scaling of this biomass production technology for outdoor conditions in the MediterraneanThe authors would like to thank to Comisión Nacional de Investigación Ciencia y Tecnología (CONICYT) from Chile for supporting the scholarship “Beca de Gestión Propia,” which finances the PhD studies of C. Fuentes-Grünewald; and to Spanish Ministry of Science and Innovation for supporting the work of E. Garcés and S. Rossi by the Ramon and Cajal award. The authors would like also to thank S. Fraga for providing the clonal culture AMP4, Laura del Río and Xavi Leal for their help with the experiments, and the Zona Acuarios Experimentales (ZAE) of the ICM-CSIC for the use of their facilities. The authors would like also to thank to project Ecotech SudoeSOE2/P2/E377 for its financial support.Peer reviewe

Parameterization Models for Pesticide Exposure via Crop Consumption

An approach for estimating human exposure to pesticides via consumption of six important food crops is presented that can be used to extend multimedia models applied in health risk and life cycle impact assessment. We first assessed the variation of model output (pesticide residues per kg applied) as a function of model input variables (substance, crop, and environmental properties) including their possible correlations using matrix algebra. We identified five key parameters responsible for between 80% and 93% of the variation in pesticide residues, namely time between substance application and crop harvest, degradation half-lives in crops and on crop surfaces, overall residence times in soil, and substance molecular weight. Partition coefficients also play an important role for fruit trees and tomato (Kow), potato (Koc), and lettuce (Kaw, Kow). Focusing on these parameters, we develop crop-specific models by parametrizing a complex fate and exposure assessment framework. The parametric models thereby reflect the framework's physical and chemical mechanisms and predict pesticide residues in harvest using linear combinations of crop, crop surface, and soil compartments. Parametric model results correspond well with results from the complex framework for 1540 substance-crop combinations with total deviations between a factor 4 (potato) and a factor 66 (lettuce). Predicted residues also correspond well with experimental data previously used to evaluate the complex framework. Pesticide mass in harvest can finally be combined with reduction factors accounting for food processing to estimate human exposure from crop consumption. All parametric models can be easily implemented into existing assessment frameworks