From first generation biofuels to advanced solar biofuels

TLDR

EU bioeconomy roadmaps largely depend on biomass, yet its low efficiency and land‑use ethics limit fossil fuel replacement, prompting a shift toward solar biofuels engineered via synthetic biology in microorganisms or synthetic factories. The paper reviews challenges and opportunities for sustainably boosting biomass production and highlights future technologies for direct solar‑to‑fuel conversion. The authors discuss how synthetic biology can enable direct conversion of sunlight, water, and CO₂ into fuel using engineered photosynthetic microorganisms or synthetic living factories.

Abstract

Roadmaps towards sustainable bioeconomy, including the production of biofuels, in many EU countries mostly rely on biomass use. However, although biomass is renewable, the efficiency of biomass production is too low to be able to fully replace the fossil fuels. The use of land for fuel production also introduces ethical problems in increasing the food price. Harvesting solar energy by the photosynthetic machinery of plants and autotrophic microorganisms is the basis for all biomass production. This paper describes current challenges and possibilities to sustainably increase the biomass production and highlights future technologies to further enhance biofuel production directly from sunlight. The biggest scientific breakthroughs are expected to rely on a new technology called “synthetic biology”, which makes engineering of biological systems possible. It will enable direct conversion of solar energy to a fuel from inexhaustible raw materials: sun light, water and CO2. In the future, such solar biofuels are expected to be produced in engineered photosynthetic microorganisms or in completely synthetic living factories.