Environmental control systems for manned lunar and planetary bases will require condensing heat exchangers to control humidity. Condensing surfaces must be hydrophilic to ensure efficient operation and biocidal to prevent growth of microbes in the moist, condensing environment. The coatings must be extremely stable and adhere to the condensing surface for many years. We propose an innovative condenser that will enable highly efficient heat transfer using an innovative coating that has proven to be highly biocidal, hydrophilic, and stable. In Phase I we will prove feasibility by demonstrating the performance of the proposed hydrophilic and biocidal surface under prototypical conditions. In Phase II we will demonstrate a full-size, prototype condenser designed to meet the requirements for future lunar and planetary bases.