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Abstract: Solar energy is one of renewable energy sources which have potential for future energy applications. New technology developments in solar energy utilization are expected to result in the improvement of the photovoltaic performance with lower production cost. This will increase the demand and viability for commercial applications. The current popular technology converts solar energy into electricity and heat separately. The photovoltaic-thermal (PV/T) hybrid system is designed to generate thermal and electrical energy simultaneously. It is well known that using a hybrid system can eliminate the need for external source of electrical energy. This paper presents research and development activity being carried out at Solar Energy Research Institute (SERI), Universiti Kebangsaan Malaysia in order to realise the technology. [Copyright &y& Elsevier]

Abstract: Heat pump system has been research and developed for different applications and mostly in space heating, cooling and dehumidifying (drying). To improve the performance of the heat pump system, research on modifying heat pump system and combining to other mechanism has been done widely. Heat pump dryer is proven as drying system that ensure the product''s quality especially food and agriculture products, able to control drying temperature, relative humidity, moisture contain extraction, drying air velocity, drying period and etc. Factor to be concern in improving a heat pump dryer includes the installation cost, drying performance such as air velocity, drying temperature and relative humidity, performance of the component hybrid to heat pump dryer, power required to run the system and also payback period. By improving the development of heat pump dryer will help increase the product quality and reducing operation cost of drying industry. [Copyright &y& Elsevier]

Abstract: Flat plate photovoltaic/thermal (PV/T) solar collector produces both thermal energy and electricity simultaneously. This paper presents the state-of-the-art on flat plate PV/T collector classification, design and performance evaluation of water, air and combination of water and/or air based. This review also covers the future development of flat plate PV/T solar collector on building integrated photovoltaic (BIPV) and building integrated photovoltaic/thermal (BIPVT) applications. Different designs feature and performance of flat plate PV/T solar collectors have been compared and discussed. Future research and development (R&D) works have been elaborated. The tube and sheet design is the simplest and easiest to be manufactured, even though, the efficiency is 2% lower compared to other types of collectors such as, channel, free flow and two-absorber. It is clear from the review that for both air and water based PV/T solar collectors, the important key factors that influenced the efficiency of the system are the area where the collector covered, the number of passes and the gap between the absorber collector and solar cells. From the literature review, it is obvious that the flat plate PV/T solar collector is an alternative promising system for low-energy applications in residential, industrial and commercial buildings. Other possible areas for the future works of BIPVT are also mentioned. [Copyright &y& Elsevier]

Abstract: A hybrid photovoltaic–thermal (PV/T) solar air heater system which generates both electricity and heat energy simultaneously was studied. Mathematical model and test results are presented. This hybrid system consists of monocrystalline silicon cells pasted to an absorber plate with fins attached at the other side of the absorber surface. Air as heat removing fluid is made to flow through an upper channel and then under the absorber plate or lower channel of the collector. Only a small part of the absorbed solar radiation is converted to electricity, while the rest increases the temperature of the cells. Improvements to the total efficiency of the system can be achieved by the use of a double-pass collector system and fins. It gives more interesting hybrid photovoltaic-thermal system design for practical applications. [Copyright &y& Elsevier]

Highlights: [•] Drying models curve of red seaweed is presented. [•] The main objective is energy and exergy analyses of the solar drying system of red seaweed. [•] The performances, exergy efficiency and improvement potential are presented. [Copyright &y& Elsevier]

Nanofluids, which are new generation cooling fluids, have been found to improve the heat transfer coefficient and enhance the system performance in recent years. In this observation, TiO 2 /water nanofluid (with 0.5 wt% and 1 wt% TiO 2) is used as a coolant to investigate the photovoltaic thermal (PVT) collector under solar radiation intensities of 500, 700 and 900 W/m2 and mass flow rates ranging from 0.012 kg/s to 0.0255 kg/s. At high solar radiation, the thermal energy efficiency is high but is inversely proportional to the electrical energy efficiency due to the increment in PV surface temperature. The energy efficiency of 1 wt% TiO 2 nanofluid-based PVT collector is 85%–89% compared with 60%–76% of water-based collector at 0.0255 kg/s. The improvement in exergy efficiency of 1.0 wt% TiO 2 is 6.02% compared with that of water-based collector at the mass flow rate of 0.0255 kg/s. In addition, a new theoretical approach model is developed to compare the theoretical and experimental results of the TiO 2 /water nanofluid-based PVT collector. Considerably close agreement between the new theoretical approaches and experimental is obtained with an accuracy of 97.6%–99.2%. • The developed novel theoretical approach for TiO 2 /water-based photovoltaic thermal (PVT) collector is presented. • The novel theoretical approach is consistent with the experiments with accuracy of 97.6% to 99.2%. • The energy efficiency of 1wt% TiO 2 nanofluid-based PVT collector is 85% to 89% as compared to water-based with 60% to 76%. • The improvement of exergy efficiency of 1.0 wt% TiO 2 is 6.02% as compared to water-based PVT collector. [ABSTRACT FROM AUTHOR]

Solar drying systems (SDSs) are environment friendly and enhance energy conservation. Such systems are a promising application of solar energy systems. SDS is an effective means of food preservation, particularly for small groups of farmers and fishers in Malaysia. Thus, these systems have been developed for agricultural and marine products in this country. This review describes the design and performance levels of different types of commercial-scale SDSs with air-based solar collectors established in Malaysia. To this end, the performances of various such SDSs are summarized in detail. Performance indices are presented as well, such as those for drying time, evaporative capacity, and drying efficiencies. Moreover, the SDSs are subject to energy–exergy–environment–economic analysis in this review. [ABSTRACT FROM AUTHOR]

Highlights: [•] Performances analysis of BIPVT solar collector based on energy and exergy analyses. [•] A new absorber design of BIPVT solar collector is presented. [•] BIPVT solar collector is produced primary-energy saving efficiency from about 73% to 81%. [•] PVT energy efficiency varies between 55% and 62% where as the variation in the PVT exergy efficiency is from 12% to 14%. [•] The improvement potential is between 98 and 404W. [Copyright &y& Elsevier]