Integrating social values into a techno-economic assessment model: An Algae case

Abstract

Most algae cultivation systems can be described as either open or closed photobioreactors through which microalgae are able to take up CO2 as a carbon source during photosynthesis. This can be an example of carbon capture & utilization (CCU) technologies for which typically, the implications of CCU technologies are calculated in terms of economic and technical indices while social factors are usually neglected in the majority of impact evaluations in the past, as they are not easy to be quantitatively analyzed, although at the local scale the social impacts might be very remarkable. Given that, key gaps remain in terms of: first, how the social dimension is understood and second, how well it is integrated into sustainability assessments which are mainly focused on environmental performance and techno-economic assessments of such innovative technologies. This research aims to fill these gaps firstly through identifying the main social impacts of the CCU technologies in order to address the second gap by developing a suitable methodology for integrating this important dimension into a techno-economic assessment (TEA) model. There is only a limited perception of how companies understand the relevance of social performance concerns and what indicators they identify as specifically applicable in decision making. Using both quantitative and qualitative approaches, this study aims to assess social impacts of a Belgian case study working with algae cultivation systems. Firstly, a survey among European CCU experts were conducted to identify the social indicators of high importance. This was done using a modified- Technique for Order Preference by Similarity to Ideal Solution (TOPSIS) method, the relative importance of the social impact (sub)categories and their related indicators for measuring social impacts were identified based on the list of potential social impact categories suggested by UNEP/SETAC guidelines (2009). Three relevant stakeholders (workers, consumers and local community) were considered as the main social impact categories through the life cycle phases of CCU activities. Afterwards, a quantitative approach was developed for measuring and developing the social model for the case study. In order to integrate the social model into the TEA, a semi-quantitative approach was developed to determine how changes in social indicators might affect the economic variables within the TEA model.The results of our study can enable companies to pay more attentions to the most important social areas when implementing such innovative technologies at higher TRLs. The proposed approach can be a useful decision making platform for decision-makers to develop more effective policies and guide the offering of incentives to the right domains for sustainable CCU activities from social and economic perspectives.