Assessing Microalgal Biodiesel Sustainability via MCI and LCA Frameworks

Natural resource extraction have increased three folds during the last four decades. Of which, economic development has been its main driving factor. Ensuring material security and environmental sustainability is of utmost importance for a sustainable economic growth. Circular economy addresses this challenge, via promoting reutilization of a product’s components and promoting value durability. It promotes a closed loop economy which reduces virgin resource extraction and promotes recycling. The energy requirement for this economic system will require energy sources of high recycling potential. A good candidate may be found in biofuels, because of its quick reutilization of the atmospheric carbon dioxide. Currently, one of the most promising feedstocks for biofuels is microalgae. It has the capacity to grow in non-arable land and produce significant amounts of oil per hectare. Several studies have assessed the environmental impact of its production, but none has considered its applicability in a circular economy. In this paper, we propose the frameworks of life cycle assessment and the material circularity indicator by the Ellen MacArthur foundation to assess the applicability of microalgal biodiesel in a circular economy. We utilized the life cycle assessment frameworks in assessing the feedstock’s impact to global warming, resource depletion, and bulk waste, while the material circularity indicator is utilized to quantify its reutilization. Comparison was carried out to jatropha biodiesel as a reference feedstock due to its similar popularity. The results of the study can provide new perspectives on how to promote microalgal biodiesel in a circular economy.