This article discusses the paired photoelectrochemical conversion of CO₂/H₂O and glycerol at high rate using a continuous-flow PEC cell. The study demonstrates that concentrated sunlight can achieve current densities similar to electrochemical methods, but with lower energy input. By combining the direct PEC oxidation of glycerol with dark hydrogen evolution or CO₂ reduction, the researchers achieved over 110 mA cm⁻² photocurrent density, which is an order of magnitude higher than previously reported. The PEC approach suppresses parasitic oxygen evolution and allows for more selective reactions. The study highlights the potential of PEC methods to drive complex electrochemical reactions with higher selectivity and lower energy consumption. The article also discusses the challenges of electrocatalysis, such as the need for selective catalysts and low-cost materials, and how PEC methods can address these issues. The research presents a PEC cell design with an n-type silicon-based photoanode and dark gas diffusion cathode for the combined reduction of water or CO₂ and oxidation of glycerol. The study shows that PEC methods can achieve lower voltage requirements and higher selectivity at high current densities by decoupling overpotential and charge carrier generation. The results indicate that the PEC cell can effectively perform paired CO₂ reduction and glycerol oxidation without complete mineralization of glycerol. The study also explores the effect of operational parameters on product distribution and reaction pathways, and concludes that PEC methods offer a promising approach for high-rate, selective electrochemical reactions.This article discusses the paired photoelectrochemical conversion of CO₂/H₂O and glycerol at high rate using a continuous-flow PEC cell. The study demonstrates that concentrated sunlight can achieve current densities similar to electrochemical methods, but with lower energy input. By combining the direct PEC oxidation of glycerol with dark hydrogen evolution or CO₂ reduction, the researchers achieved over 110 mA cm⁻² photocurrent density, which is an order of magnitude higher than previously reported. The PEC approach suppresses parasitic oxygen evolution and allows for more selective reactions. The study highlights the potential of PEC methods to drive complex electrochemical reactions with higher selectivity and lower energy consumption. The article also discusses the challenges of electrocatalysis, such as the need for selective catalysts and low-cost materials, and how PEC methods can address these issues. The research presents a PEC cell design with an n-type silicon-based photoanode and dark gas diffusion cathode for the combined reduction of water or CO₂ and oxidation of glycerol. The study shows that PEC methods can achieve lower voltage requirements and higher selectivity at high current densities by decoupling overpotential and charge carrier generation. The results indicate that the PEC cell can effectively perform paired CO₂ reduction and glycerol oxidation without complete mineralization of glycerol. The study also explores the effect of operational parameters on product distribution and reaction pathways, and concludes that PEC methods offer a promising approach for high-rate, selective electrochemical reactions.