To prevent the increase in global warming potential, it is necessary to enhance the energy efficiency of refrigerant-powered systems. Therefore evaporative cooling systems are of particular importance. The option of adiabatic cooling without adding humidity into the supply air flow causes that indirect evaporative cooling (IEC) is considered advantageous although there is a risk of aerosols being discharged into the exhaust air. IEC is almost exclusively used in large HVAC devices. There is currently a lack of suitable solution approach on the market for smaller decentralized or retrofit devices. To implement the positive effects of IEC in current buildings and to solve the aerosol problem, the ILK Dresden is developing an innovative cooling panel with a novel membrane heat exchanger (MHE). Therein water evaporates through a vapour permeable membrane into the exhaust air flow. The cooling effect on the supply air side is achieved via a barrier film. Two options, the “evaporative cooling by using supply air recirculation” and “exhaust air humidification in an air-to-air heat recovery system” are being further developed so that they can be used in the new cooling panel. The novel MHE is assembled by stacking 4-layer textile laminates. New processing methods and material combinations have been developed for their manufacture. Based on the requirements profile, results from the first development phases (conception, preliminary material investigations, thermodynamic design, constructive implementation and measurement analyses) are presented. Finally, an outlook is given on the optimization and application potential of IEC via membranes in HVAC systems.