Electro-biodiesel empowered by co-design of microorganism and electrocatalysis

Abstract

Efficient and sustainable energy production is essential for climate change mitigation, yet current approaches like biofuels or electro-fuels have limitations in efficiency and product profile. We advanced a new electro-biodiesel route via integrating electrocatalysis and bioconversion to produce lipids from CO₂ for biodiesel. We first revealed bioenergetic and metabolic limits in C2+ intermediate utilization through simulations and metabolomics, guiding the synthetic biology design to achieve reductant balance, more ATP production, efficient lipid conversion, and higher lipid yield. Furthermore, we discovered specific ratios of ethanol and acetate to achieve co-substrate synergy, empowering bimetallic catalyst design to improve bioconversion efficiency. The microbial and catalyst co-design achieved a solar-energy-to-molecule conversion efficiency of 4.5% for CO₂-to-lipid conversion. Electro-biodiesel leverages the high efficiency of electrocatalysis and longer-carbon-chain products from microbial lipid synthesis, overcoming the limitations for both electrocatalysis and bioconversion. Electro-biodiesel achieved 45 times less land usage than soybean biodiesel, competitive economics, and substantial carbon emission reduction.