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High initial cost of power plant, limited power capacity of the existing plant and the frequent black out of many districts due to the continuous increase in electrical demands, in addition to the adverse effect of the blackout on hypermarkets, especially on foodstuff such as meat, chicken, etc. strongly encourage the adoption of a regenerating process and the principle of combined heat and power. This work investigates the upgrading of the combined cooling heat and power system and improving the regenerating process adopted in the first design of an existing project. Linking between refrigeration and air-conditioning systems is proposed in scheme-II. A single-effect absorption chiller operating in the range of refrigeration scale (i.e. aqueousammonia refrigeration, not air-conditioning scale, LiBr-H 2 O employed in scheme-I) will be adopted using pressurised hot water recovered from the generators. The chilled water system will be serving three categories in the following order, namely, refrigeration stores, cold stores and air-conditioning units, respectively. The chilled water output of the first category will be the input of the second one. This will enhance the overall system efficiency, reduce the generator load and lessen the fugitive refrigerant emissions, which mainly participate in ozone-depleting potential and global-warming potential. This is in addition to the dramatic reduction in initial and operating cost, which can be estimated to be 50% and 79.6%, respectively.

International concern about the environmental implications of climate change coupled with increasing demand for energy to fuel modern society has lead to growing interest in using renewable energy sources as alternatives to conventional sources. The work presented in this paper compares two types of solar collector integrated into louvred shading devices. In addition to protecting glazed spaces in buildings from excessive solar gain, the collector would provide the flexibility to produce systems customized for collecting heat over a temperature-range appropriate to particular building services applications at various climates/locations. This would allow considerable savings to be made in primary energy consumption and lead to a reduction in global warming impact. Two solar absorbers, based on different techniques of heat exchange, were tested experimentally. The first was based on a direct heat exchange technique, and the second used heat pipe technology. Various comparisons were made and it was concluded that the heat pipe solar louvre collector was the preferred device.

Most conventional cooling/refrigeration systems are driven by fossil fuel combustion, and therefore give rise to emission of environmentally damaging pollutants. In addition, many cooling systems employ refrigerants, which are also harmful to the environment in terms of their Global Warming Potential (GWP) and Ozone Depletion Potential (ODP). Development of a passive or hybrid solar-driven air-conditioning system is therefore of interest as exploitation of such systems would reduce the demand for grid electricity particularly at times of peak load. This paper presents a review of various cooling cycles and summarises work carried out on solar-driven air-conditioning systems.