The article "Comparing Photosynthetic and Photovoltaic Efficiencies and Recognizing the Potential for Improvement" by Robert E. Blankenship, David M. Tiede, James Barber, and others, published in Science, 332(6031), discusses the comparison of photosynthetic and photovoltaic (PV) energy conversion efficiencies. The authors highlight the differences in how these processes operate and produce different outputs: biomass or chemical fuels from natural photosynthesis, and non-stored electrical current from PV systems. They compare the annual efficiency of PV-driven electrolysis of water to produce hydrogen, which is about 14%, with the short-term yields of photosynthetic conversion under optimal conditions, which can reach up to 7% for microalgae. The article also explores the theoretical limits of both systems, noting that PV systems can achieve a maximal efficiency of around 32% at one-sun intensity, while photosynthetic glucose production has a theoretical limit of about 12%. The authors discuss various strategies to improve the efficiency of both systems, including the use of tandem cells in PV systems and the optimization of light-absorbing pigments in photosynthetic organisms. They emphasize the potential of synthetic biology to enhance photosynthetic efficiency through genetic engineering and more radical redesigns of the photosynthetic apparatus. Overall, the article argues that while PV systems currently have higher efficiency, there are significant opportunities to improve the efficiency of natural photosynthesis through targeted modifications and the application of synthetic biology techniques.The article "Comparing Photosynthetic and Photovoltaic Efficiencies and Recognizing the Potential for Improvement" by Robert E. Blankenship, David M. Tiede, James Barber, and others, published in Science, 332(6031), discusses the comparison of photosynthetic and photovoltaic (PV) energy conversion efficiencies. The authors highlight the differences in how these processes operate and produce different outputs: biomass or chemical fuels from natural photosynthesis, and non-stored electrical current from PV systems. They compare the annual efficiency of PV-driven electrolysis of water to produce hydrogen, which is about 14%, with the short-term yields of photosynthetic conversion under optimal conditions, which can reach up to 7% for microalgae. The article also explores the theoretical limits of both systems, noting that PV systems can achieve a maximal efficiency of around 32% at one-sun intensity, while photosynthetic glucose production has a theoretical limit of about 12%. The authors discuss various strategies to improve the efficiency of both systems, including the use of tandem cells in PV systems and the optimization of light-absorbing pigments in photosynthetic organisms. They emphasize the potential of synthetic biology to enhance photosynthetic efficiency through genetic engineering and more radical redesigns of the photosynthetic apparatus. Overall, the article argues that while PV systems currently have higher efficiency, there are significant opportunities to improve the efficiency of natural photosynthesis through targeted modifications and the application of synthetic biology techniques.