Evaluation of economic feasibility for the microbial electrosynthesis-based β-farnesene production technology: Process modeling and techno-economic assessment

Abstract

Microbial electrosynthesis (MES) is a promising technology for converting CO₂ and renewable electricity into high-value hydrocarbons by utilizing electro-active microorganisms in combination with an electrode (i.e., the cathode). This study proposes a novel process for producing β-farnesene (C₁₅H₂₄), a bio jet-fuel precursor, from a CO₂ feedstock using the MES reactor coupled with a series of separation and purification unit operations. A metabolically-engineered Rhodobacter sphaeroides strain was employed as the cathodic biocatalyst to promote β-farnesene production. Based on the lab-scale experimental data from the MES reaction, a commercial-scale process model for β-farnesene production was developed and simulated to achieve an annual production capacity of 5000 metric tons. The techno-economic assessment (TEA) of the process revealed a levelized cost of production (LCOP) of $2.94/kg for β-farnesene, which is competitive with existing sugar-based technology, such as Amyris’s process, which has an LCOP of $4.9/kg. These findings prove that MES-based β-farnesene production technology is an attractive approach for producing bio jet-fuel in terms of price competitiveness and future market demand.