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Abstract: A solar-assisted chemical heat-pump dryer has been designed, fabricated and tested. The performance of the system has been studied under the meteorological conditions of Malaysia. The system consists of four main components: solar collector (evacuated tubes type), storage tank, solid–gas chemical heat pump unit and dryer chamber. A solid–gas chemical heat pump unit consists of reactor, condenser and evaporator. The reaction used in this study (CaCl2–NH3). A simulation has been developed, and the predicted results are compared with those obtained from experiments. The maximum efficiency for evacuated tubes solar collector of 80% has been predicted against the maximum experiment of 74%. The maximum values of solar fraction from the simulation and experiment are 0.795 and 0.713, respectively, whereas the coefficient of performance of chemical heat pump (COP h ) maximum values 2.2 and 2 are obtained from simulation and experiments, respectively. The results show that any reduction of energy at condenser as a result of the decrease in solar radiation will decrease the coefficient of performance of chemical heat pump as well as decrease the efficiency of drying. [ABSTRACT FROM AUTHOR]

Abstract: Solar energy is the most promising source of clean, renewable energy and it has the greatest potential of any power source to solve the world''s energy problems. However, the problem, is how best to harness this vast amount of solar energy. Nevertheless, even if highly efficient Concentrating Solar Power (CSP) could be made cheaply, there would be considerable change in solar power. This technology is expected to be more efficient and to achieve a manufacturing cost of less than $1/W near future. This paper reviews and elaborates the methodology utilized to design and fabricate the solar dish concentrator and outlines the parameters that can be used to increase the efficiency of solar fraction in parabolic dish concentrator under wet climate environment in Malaysia. The study finally provides ideas to the continually increasing ability of these technologies to concentrate and harness solar energy for electricity production and thus eliminate the growing concern over climate change and how it will hurt the region''s environment, human health and economy. [Copyright &y& Elsevier]

The performance of a solar-assisted chemical heat pump dryer has been studied under the meteorological conditions of Malaysia. The system consists of four mean components: solar collector (evacuated tubes type), storage tank, solid–gas chemical heat pump (CHP) unit and dryer chamber. A solid–gas CHP unit consists of a reactor, condenser and evaporator. The reaction (CaCl2–NH3) has been used in this study. A series of experiments have been performed on the system under varied conditions for two days. The maximum values of solar fraction from the experiments on clear and cloudy days are 0.713 and 0.322, respectively; whereas the coefficient of performance of CHP (COPh) maximum values of 2 and 1.42 are obtained from the experiments on clear and cloudy days, respectively. The total system energy output from the experiment on a clear day is 51 kWh against 25 kWh on a cloudy day. Any reduction of energy at the condenser as a result of decrease in solar radiation will decrease the coefficient of performance as well as the efficiency of drying. [ABSTRACT FROM AUTHOR]