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Electric vehicles (EV) are a relatively contemporary and emerging technology in the transportation and power sectors, with several economic and environmental advantages. However, there are still challenges associated with EV charging depending on on-grid electricity. University buildings that consume a lot of energy continue to rely on the grid and/or conventional fuel for consumption. In addition, EV Charging will create more challenges in meeting the demand; therefore, utilizing university rooftops for EV charging has high prospects of meeting the additional energy demand. In Malaysia, no such research has been presented that has explored the possibility of using academic institute rooftops for BIPV installation for EV Charging in terms of energy and environmental standpoint. The current study analyzes and evaluates a rooftop grid-connected Building Integrated photovoltaic (BIPV) system for generating electricity and EV charging at the University Malaysia Pahang, Malaysia, for EV charging. The system’s energy output has been simulated using the PVSyst in two scenarios, i.e., fully integrated with no ventilation and free mounted with air circulation. It was found that 7000 m2 of the selected building’s rooftop area could be used for panel installation. The panels’ total capacity was 1.069 MW, with total annual electricity production of 1587 MWh and 1669 MWh in respective scenarios. The proposed BIPV plant would reduce GHG emissions of 60,031 tons of CO2e in scenarios 1 and 61,191 tons of CO2 in scenario 2 compared to the emission produced by coal plants for the same amount of annual energy generation.

Abstract.One of the problems faced in stingless bee honey storage is spoilage by the fermentation process occurs in honey due to its high water content. There are a few techniques available currently, but they are time consuming and there is excessive heat involved in the process. The temperature of the process must be kept low because excessive heat can deteriorate nutrition value and biochemical content in honey. Hence, a new method of honey dewatering was developed using a Low Temperature Vacuum Drying (LTVD) with induced nucleation technique.The objective of this research is to investigate the performance of a LTVD with induced nucleation to reduce the water content in honey. First, the honey was placed in a pressure vessel, and then air was removed. Then, the honey was slightly heated at 30ºC and the water content before and after the experiment was measured by a refractometer. The steps were repeated until the water content reached below 20%. It was found that the LTVD method improved the water removal rate significantly with an average of 0.15% of water content per minute. That is 3 times much faster than the conventional method of low temperature heating by Tabouret. Higher temperature during dewatering process improved the dewatering rate significantly. It can be concluded that LTVD is a promising option in tackling the high water content in stingless bee honey issue.

Numerous air conditioners are running without a proper refrigerant charge due to leakage and improper charging during installation. Therefore, there is a need to understand the performance of the air conditioner if it is not properly charged for the means of optimal operation and cost saving. This study is focusing on the usage of a used small capacity split-unit type air conditioner using R-22 refrigerant. The objective is to study the condenser performance over a variation of refrigerant charges. From the results, it is clear that the optimum refrigerant charge is 100%. The highest cooling capacity and COP were 3,330 J/s and 3.05 respectively.