Along with their use in biological systems, enzymes are being explored in electrochemical CO2R primarily due to their high energy efficiency (low overpotential) and catalytic rates. Enzymes also approach a selectivity of 100% and display a high affinity for CO2 due to Michaelis-Menten kinetics. These properties offer potentially significant advantages but have not yet been explored for the utilization of low CO2 concentrations. The fuel-forming enzyme formate dehydrogenase (FDh) has previously been combined with CA for enzymatic CO2R to demonstrate that CO2 (and not HCO3 -) is the substrate of FDh. In addition, CA has been used to catalyze the conversion of CO2 to HCO3 -, decreasing local CO2 concentrations and increasing HCO3 - and H + (directly contrasting its role in increasing CO2 concentrations in the carboxysome) either to mitigate local pH changes in saturated CO2 or for the use of HCO3 -as a substrate. Enzymatic CO2R at low CO2 concentrations with CA has also relied on an energy inefficient NADH cofactor recycling system to transfer electrons from an electrode to enzymes in bulk solution giving a low FE and offering no capability to mimic the nanoconfined environment of a carboxysome on an electrode , a property that may be highly beneficial for CO2R at reduced rates as it has been shown to improve enzyme's affinity for substrate and kinetic rates. CA has also been used in carbon capture systems to increase the kinetics of CO2 capture as HCO3 - and release of carbon capture, but the Faradaic Efficiency (FE) has been significantly reduced when this capture media has been used for electrolysis. While most carbon capture has focused on producing concentrated CO2 gas streams or concentrated capture media, the integration of capture and utilization into a single system that uses low concentrations of CO2, ideally down to atmospheric concentrations, offers the potential to minimize the energy and complexity requirements of this process in the manner of the biological carboxysome. In this work, we adapt strategies employed by carboxysomes to enhance direct CO2R from low-concentration sources by increasing local CO2 concentrations (flue gas to atmospheric concentrations, 10% -420 ppm in N2). CO2R is performed under nanoconfinement within mesoporous indium tin oxide (ITO) electrodes (SI Figure and S2) to manage the concentration of compartmentalized CO2, HCO3 -, and H + , which are crucial to CO2R performance. Within the porous electrode, CA accelerates the kinetically slow interconversion between HCO3 -and CO2, allowing for the utilization of the total dissolved carbon pool to offset local CO2 depletion (Figure ). The buffer capacity and pH of electrolytes used in this work are altered to raise local HCO3 -concentrations, which can be converted to CO2 by CA to mitigate local substrate consumption. With these interventions we raise local CO2 levels within the nanoconfined electrode, offsetting diffusion gradients and substrate depletion that primarily limit enzymatic fuel production from dilute gas streams. Through these methods we have demonstrated a nanoconfined carboxysome-inspired system for the reduction of low concentrations CO2 streams, down to atmospheric levels, to formate. This produces quantifiable product concentrations and is underpinned by the use of finite element modelling to provide an understanding of how solution concentrations for all carbon components can be optimized for effective system performance.