Use of Solar Regenerated Membrane-Desiccant System to Control Humidity and Decrease Energy Consumption in Office Buildings PDF

The proposed system is a hybrid air-conditioning system that uses a novel liquid desiccant cycle with porous membrane material. The cycle is integrated with a conventional HVAC system to allow for independent control of indoor humidity and temperature. Conventional liquid desiccant cycles dehumidify the air before supplying it to the indoor space, while the proposed cycle absorbs the humidity directly from indoor space using a permeable cylindrical membrane acting as a dehumidifier. The air leaving the indoor space is cooled using an evaporative cooler. The cooled air is then used to decrease the temperature of the desiccant entering the indoor space in order to reduce the sensible load that might be added to the space air and to increase the potential of the desiccant to absorb moisture. The size of the proposed cycle is significantly reduced as compared to the conventional cycles that rely on evaporative cooling towers or regenerators or even desiccant wheels. The regeneration of the desiccant is also done through the use of permeable membrane tubes with the aid of parabolic panels to collect solar energy. An integrated mathematical model of the permeable membrane with the space modal was developed to study the feasibility and efficiency of the proposed cycle. It was found that the system can achieve a 32-35% reduction in electric energy consumption compared to conventional air conditioning systems operating on a typical office of size 4 mx5 mx6 m.