In tropical climates, a rising demand for active air-conditioning leads to a strong increase of electricity consumption. Compared to the energy demand for the sensible cooling of air the high humidity (in the order of 20 g water per kg dry air) in the tropics results in a significantly high air-dehumidification load. Handling the dehumidification load and sensible cooling load separately can reduce the electricity demand for air-conditioning considerably if the dehumidification is driven by heat energy (e.g. solar thermal or waste heat) instead of electricity. At the Solar Energy Research Institute of Singapore (SERIS), an experimental two-stage air-dehumidification system consisting of a membrane unit and an adsorption based desiccant unit, has been installed and analysed. The membrane unit pre-dehumidifies the ambient air, which is then further dehumidified and simultaneous evaporatively cooled by an Evaporatively COoled Sorptive (ECOS) dehumidification and heat exchange unit. The aim of this study is to evaluate the dehumidification performance of the two-stage air-dehumidification system under tropical climate conditions and different operating parameters such as air flow rate and regeneration air temperature. A numerical model was developed for the ECOS and the membrane unit in MATLAB which was then coupled with TRNSYS software in order to create a model for the two-stage dehumidification system. The results of our investigations show that the two-stage system is able to dehumidify ambient air by 8 to 10 g water per kg of dry air under the warm and humid climate conditions of Singapore. Thermal COP of up to 0.6 was obtained

Global industrial energy consumption amounts to 3616.93 TWh of oil and oil products, 6059 TWh of gas and 8245.60TWh of electricity [1]. About two-third of this industrial energy is considered to utilize for industrial heating processes, also known as `industrial process heat'. With a goal to energy security and environmental sustainability, solar thermal system can be considered as an alternative solution for industrial heating applications. Solar thermal systems integrated with the industrial process heat for low temperature (60 - 120 °C) has a greater potential because of wider range of industrial applications. This paper studies a solar thermal system providing industrial heat required for a dairy industry. A TRNSYS simulation model has been developed to study the solar thermal systems performance for three different climatic conditions-Cyprus, France (Lyon) and Morocco (Casablanca). An optimum collector model has been analysed with evacuated tube collector technology and found out that solar thermal system meets-89%,76 % and 94% of the total heating load demand of the industry for three different regions-Cyprus, France and Morocco respectively.

At present, climate change and rising energy prices motivate the researchers to focus on better utilization of energy for space cooling applications. The chilled beam system has already been widely used in Europe for better utilization of energy for space cooling. But, the condensation on the chilled ceiling panel limits its application in the hot and humid climates. Operating a chilled beam system for such warm and humid climate requires the integration of desiccant system, which needs to be regenerated thermally for the purpose of the indoor air quality control. This paper emphasis the performance analysis of a thermally regenerated desiccant system integrated with a building chilled beam system in Singapore. A TRNSYS simulation model of such system has been developed to investigate the thermal performance. In this model, the chilled beam system meets the sensible load of the cooling space, while the desiccant air handling system meets the latent load of the cooling space. To regenerate this desiccant system, different heat sources such as solar, electricity and waste heat are considered in the analysis. It has been found that this integrated desiccant system with active chilled beam meets the cooling load (space temperature 21°C to 25°C and relative humidity between 55% ∼ 65%) of an office building effectively. It has also been found that the utilization of solar energy as heat source for desiccant regeneration decreases the energy consumption of the system at about 20% and reduces the operating cooling cost at about 1.5 to 2.5 times than the conventional VAV system.