Ocean-Powered Pump for Global Cooling and Increased Food Production

Cold water pumped up from the deep ocean and spread out on the surface may be a way to cool the Earth´s surface while providing macro- and micro-nutrients needed by phytoplankton in the surface layer. The resulting increased photosynthesis converts the carbon dioxide (CO₂) dissolved in the water into increased phytoplankton mass, which feeds zooplankton and other members of the marine food chain. Uneaten organic matter sinks to the bottom, sequestering the CO₂ that is absorbed from the atmosphere. This photosynthetic process (the biological pump) avoids an inorganic process in which excess CO₂ reduces the alkalinity of the ocean and interferes with the formation of shells and skeletons of marine life forms. The pumps are powered by an ocean thermal energy conversion (OTEC) process that has been in development for more than 100 years without achieving large-scale commercial success. This paper describes an OTEC design modification that increases the heat engine efficiency and can lead to large-scale deployment of OTEC-powered pumps.