Description:
Carbon, as a major component of most fuels and materials, is the backbone of the modern global economy. Currently this requires reliance on fossilized carbon-based products which present sustainability, resource management, and greenhouse gas (GHG) exacerbated climate change challenges. Due to these challenges, there is the need for a global industrial transition towards sustainable production with greater circularity in carbon and natural resource flows. Specifically, new pathways to realize low-, zero-, or negative-carbon fuels, chemicals, and materials need to be established. The sustainable use of renewable biomass (aquatic and terrestrial) for energy, intermediate, and final products, termed the “bioeconomy”, is one promising approach to pursue; and beyond offering a promising source of renewable carbon, biomass utilization has been shown to provide additional economic, environmental, social, and national security benefits as well.
A robust and sustainable bioeconomy can only be realized through the industrial-scale, carbon-neutral synthesis of fuels, chemicals, and materials. The rapid deployment of renewable power is driving down the cost and carbon intensity of electricity which presents the opportunity for a tradeoff: by using more clean electricity to power novel bioconversion platforms, less CO2 will be produced. This will be made possible by engineering new biorefining systems capable of using electrically derived external reducing equivalents to improve the efficiency of biomass conversion and CO2 utilization. In addition, externally sourced CO2 itself may be used as a feedstock, enabling additional carbon neutral and even carbon-negative products. Successful new platforms will serve to maximize the utility of carbon resource inputs, minimize associated land use requirements, and mitigate lifecycle GHGs simultaneously.
This funding opportunity seeks submissions to establish new technologies to significantly improve the carbon efficiency of bioconversion platforms through the accommodation of external reducing equivalents. Proposed systems of interest include, but are not limited to: (1) carbon optimized fermentation strains that avoid CO2 evolution, (2) engineered mixotrophic consortia or systems that avoid CO2 evolution, (3) biomass or gas fermentation with internal CO2 utilization, (4) cell-free carbon optimized biocatalytic biomass conversion and/or CO2 utilization, and (5) cross-cutting or other proposed carbon optimized bioconversion schemes. All systems will need to demonstrate the capacity to accommodate external reducing equivalents to optimize the carbon efficiency of the system as compared to traditional fermentation systems (i.e. the sum of the recoverable energy contents of the products is greater than the energy content of the biomass or primary carbon feedstock).
