Consequential LCA and LCC using linear programming: an illustrative example of biorefineries

Abstract

Purpose This paper aims to demonstrate how LCA can be improved by the use of linear programming (LP) (i) to determine the optimal choice between new technologies, (ii) to identify the optimal region for supplying the feedstock, and (iii) to deal with multifunctional processes without specifying a certain main product. Furthermore, the contribution of LP in the context of consequential LCA and LCC is illustrated. Methods We create a mixed integer linear program (MILP) for the environmental and economic assessment of new technologies. The model is applied in order to analyze two residual beech wood-based biorefinery concepts in Germany. In terms of the optimal consequences for the system under study, the principle of the program is to find a scaling vector that minimizes the life cycle impact indicator results of the system. We further transform the original linear program to extend the assessment by life cycle costing (LCC). Thereby, two multi-objective programming methods are used, weighted goal programming and epsilon constraint method. Results and discussion The consequential case studies demonstrate the possibility to determine optimal locations of newly developed technologies. A high number of potential system modifications can be studied simultaneously without matrix inversion. The criteria for optimal choices are represented by the objective functions and the additional constraints such as the available feedstock in a region. By combining LCA and LCC targets within a multi-objective programming approach, it is possible to address environmental and economic trade-offs in consequential decision-making. Conclusions This article shows that linear programming can be used to extend standard LCA in the field of technological choices. Additional consequential research questions can be addressed such as the determination of the optimal number of new production plants and the optimal regions for supplying the resources. The modifications of the program by additional profit requirements (LCC) into a goal program and Pareto optimization problem have been identified as promising steps toward a comprehensive multi-objective LCSA.

Resources, Collaborators, and Neighbors: The Three-Pronged Challenge in the Implementation of Bioeconomy Regions

“…Such an integrated and multi-level approach can help obtain a clearer understanding of the potential impacts caused by the increased use of biomass resources and at what scale these impacts might be occurring. Environmental, social, and economic impacts not only occur directly within the producing region, but can also be induced elsewhere, outside of these bioeconomy regions, due to the production activities of the various bioeconomy clusters and networks [26,[30][31][32][33]. This leads to a quandary of scale when making impact assessments of bio-based systems, i.e., at which scale should assessments be carried out [34].…”

ECOPT2: An adaptable life cycle assessment model for the environmentally constrained optimization of prospective technology transitions

“…Thus, ECOPT 2 aims to model the direct and indirect environmental impacts associated with an internally consistent technology transition scenario. While previous studies have combined some of these elements, such as combining LP and LCA, the focus of their work was to determine the environmentally optimal substitution mix for static systems (Budzinski et al., 2019; Saner et al., 2014; Steubing et al., 2016). In contrast, LP is used in ECOPT 2 toward understanding the dynamics of technology deployment while taking into consideration stock and material cycle dynamics.…”

“…The benefits of joint LCA and optimization approaches are two‐fold: it allows the inclusion of supply constraints, and by default, the optimization approach finds the combination of decision variables that result in the lowest environmental impacts. Examples of joint LCA‐optimization studies generally involve the selection of technologies by minimizing environmental impact, and using as decision variables, for example, the mix of substitutable products with limited supply as in Budzinski et al (2019), Saner et al (2014), and Steubing et al (2016), among others. These studies, however, have been static in nature and do not identify a transition pathway.…”

LCA Practices of Plastics and Their Recycling: A Critical Review

“…For instance, MCDA, TEA, and life cycle costing (LCC) are just a few examples of methods that can be found in some recent applications, although these are not yet widely used. This also includes the application of linear programming methods in consequential approaches, as can be found in [52]. A recent stream of LCA called the life cycle sustainability Assessment (LCSA) tends to embrace such a multi method approach [53,54].…”

“…In other LCA studies where the aim is not necessarily to perform an ex there are ample opportunities to apply other methods to support or extend t For instance, MCDA, TEA, and life cycle costing (LCC) are just a few e methods that can be found in some recent applications, although these are no used. This also includes the application of linear programming methods in co approaches, as can be found in [52]. A recent stream of LCA called the lif tainability Assessment (LCSA) tends to embrace such a multi method appro Several years ago, [55] performed a review on LCSA applications and found ods to deepen LCSA were lacking, proposing systems thinking and related tentially valuable to deepen the analyses.…”