Page 348 - Biofuels for a More Sustainable Future

304 Biofuels for a More Sustainable Future

Sammons et al., 2007, 2008; P erez et al., 2016)] to generate process-based
inventory data. However, most of previous studies developed process-based
models in separate environment with BSC design models, making the sys-
tem optimization challenging. In the future, more efforts should be made on
developing effective and robust methods to generate and collect data to bet-
ter quantify the environmental, economic, and social impacts of BSC. Some
new modeling techniques such as machine learning and big data analytics
could be a possible solution. Given the potential trade-offs among different
aspects of sustainability, how to better understand and integrate those aspects
into BSC design and modeling is another area that needs more efforts.
Asdiscussed previously, many studies used MCDAto integrate multiple objec-
tive functions into a single objective using weighting factors that are subject to
stakeholder preferences and socioeconomic and regional contexts. Given the
large impacts of weighting factors on the results, it is critical for researchers and
BSC designers to provide transparent documentation and interpretation.

6 Conclusions and future directions
In this chapter, a comprehensive review was conducted for BSC design to
present its status quo, issues, and challenges. Based on the literature included
in this review, infrastructure location, capacity selection, and network
design are the top three strategic decisions that have been mostly investigated
by previous studies. Regarding tactical and operational decisions, logistic
management related decisions are most investigated by previous studies.
Two types of approaches, optimization and simulation, are commonly used
to support decision-making in BSC design. Between the two modeling
approaches, optimization is used in more studies based on the papers
included in this review.
For optimization studies, economic objective functions such as maxi-
mizing NPV and profit or minimizing the cost at different levels are com-
monly investigated in most of BSC design cases. Environmental and social
objective functions are also considered in many studies to address more sus-
tainability issues in the BSC design. Several environmental indicators are
commonly used in reviewed studies such as GHG or different LCIA indi-
cators. These indicators can be modeled as either objective functions or con-
straints. Job creations are the most common indicators used in BSC
optimization models for social sustainability. As the increasing awareness
of sustainability, it is expected that more efforts will be made in better under-
standing and incorporating sustainability related aspects into BSC design.