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(Hybrid Photovoltaic (PV) units are systems that produce both electrical and thermal energy in a single unit. The purpose of this research is to investigate the feasibility of using PV solar waste heat to regenerate liquid desiccant in the solar air conditioning system. A typical liquid desiccant regenerator requires a temperature range between 50 ̊C and 60 ̊C. Thus, the heat recovery system is designed on a 50W solar PV that focuses on recovering, delivering, and transferring of heat from panel PV to heat the circulating water. This paper also discusses the comparison of output power and efficiency between heat recovered and a standard solar photovoltaic panel. The calculated maximum output power for heat recovered and standard solar PV system was 52.20W and 40.15W, with an efficiency of 11.72% and 9.65% respectively. The maximum temperature for the heat recovered system was 55.10 ̊C at 1.00 pm and the standard system was found at 62.30 ̊C. The experiment results show that stored water temperature in the reservoir able to reach 55 ̊C, within the range of a preferred liquid desiccant regenerator. Thus, it is possible to utilise the solar PV waste heat for desiccant solution regeneration and simultaneously benefit from the added benefit of improved efficiency.

use of solar dryers in agriculture is a technological revolution towards the modern world. In addition to being a clean source of energy, the use of this dryer produce better product than conventional method. The objective of this study is to identify the main component and their size in a special solar dryer system for kenaf fiber in Chuping. Then a test is done to see the effectiveness of drying. The methodology used is the determination of the main component, the size of each component and the performance of the solar dryer based on the relevant parameters. The main features and components identified are load, drying chamber dimensions (area-height), tank capacity and solar collector area. In addition, other components are needed for the drying to run smoothly such as pumps, heat exchanger, expansion tank and water heater. The calculation result found that the load, chamber dimension (area-height), tank capacity and collector area values were 1400kg, 58.73m²-2.5m, 1200L and 48.45m², respectively. The drying test was successfully performed within 3 days with weight and moisture content reduction of 1004.2kg and 57.96%, respectively. The drying performance assessed was the estimated drying rate from the weight reduction and drying period, which was around 68.58kg/h.

Solar assisted heat pump (SAHP) system integrates a solar thermal energy source with a heat pump. This technique is a very fundamental concept, especially for drying applications. By combining a solar thermal energy source such as solar thermal collectors and a heat pump dryer will assist in reducing the operation cost of drying and producing products with high quality. Many review papers in the literature evaluated the R&D aspects of solar-assisted heat pump dryers (SAHPD). This critical review paper studies some of the researches conducted in this field to understand and provides an update on recent developments in SAHPD. Also, a detailed explanation of principles and operation for SAHPD and its applications are presented. The used types of solar thermal collectors, as well as various heat pump dryers, are all discussed in this article. Finally, it is concluded that there is a clear lack of research in the techno-economic and environmental evaluation, while most of SAHPD studies focused on the performance study of the system.

Solar energy is one of several types of renewable energy and has numerous applications. Types of solar energy include photovoltaic, thermal, and thermophotovoltaic modes. Drying is an application of thermal solar energy which is used to remove water from a sample. The main reason this study was done was due to the lack of use of hybrid solar dryers for high load keno fibers. This dryer is capable of extracting water from the sample with a maximum load of up to 1400 kg. This study aims to evaluate certain open drying methods as compared with modern thermal drying methods. The dried samples were a type of natural fiber commonly known as kenaf (Hibiscus Cannabinus L). The test amounts were 175 kg and 1400 kg, respectively. The solar thermal drying uses several components, including an evacuated tube collector, water storage tank, heater, air intake, pump, and a drying chamber. The parameters to be measured included weight, water content, time, and electricity usage. Dryer performance was evaluated in terms of water extraction rate, exact water extraction rate, specific energy usage, dryer operational costs, and specific operational costs. The results of the evaluations indicate that drying with the maximum load of 1400 kg increased the extracted water, exact water extraction rate, and dryer operational costs by 97.27 kg/hour, 39.86 kg/kWh, and 3.72 Malaysian ringgit (approximately 0.90 USD), respectively. Specific energy consumption and specific operating costs fell by 0.10 kWh/kg and 0.05 RM/kg (0.012 USD/kg), respectively. Based on these findings, economic analysis was carried out to estimate the profitability and frequency of drying. The results indicate that a maximum load of 1400 kg is superior to the open drying method, with an annual yield and return of investment period of RM 64992 (15,723 USD) and 3.7 years, respectively

Fish cracker is one of Malaysian traditional snack food. The cracker has a huge potential to be marketed globally. However, it is obstructed by hygienic issue during preparation. Traditionally, open sun drying was used for moisture extraction, but this method exposed to contamination from bird, incest and dust. To overcome the problem, an alternative drying method was introduced by using the heat pump dryer. The purpose of this work is to evaluate drying of Malaysian Spratelloides Gracilis fish cracker originated from Kemaman. The dryer consists of drying chamber, fan, heater, and compressor. Multilevel drying trays equivalent to 7.43 m2 drying area was arranged inside the chamber. The evaluation started by measuring drying time, electricity consumption, weight, and moisture reduction. Changes of the cracker was observed and performance of the dryer was determined. At the end of this report will discuss the economic aspect by estimating annual return of investment and payback period. Result shows moisture and weight reduction are 42.9 % and 6.0 kg, respectively. Drying completed in 4 hours consuming 5 kWh electricity. Physical observation shows significant changes on dried cracker in terms of color, size, and shape. Dryer performance determined by evaporative capacity (1.5 kg/hr), specific moisture extraction rate (1.2 kg/kWh), specific energy consumption (0.8 kWh/kg), drying cost (1.09 RM) and specific drying cost (0.17 RM/kg). Based on electricity cost, selling price and production, replacing open sun drying with heat pump drying method will not affect much the new selling price because drying cost is only 0.6 %. Payback period of the dryer also estimated as 1.1 year.

Solar energy is known as renewable and clean source of energy. This tremendous amount of energy is widely used from small portable application to gigawatt size power plant generation. It has been utilized for various off grid or standalone applications including for vehicles. However, the progress of Solar Car (SC) was unsatisfied. Unlike Hydrogen Car (HC) and Pure Electric Vehicle (PEV), there is no commercialize SC marketed yet. Many strategies contributed to the successful of HC and PEV such as supportive policy, taxation, facilities and private involvement. The main component of SC can be simplified and consists of the structure, photovoltaic (PV) module, rechargeable battery pack, electric motor and power management unit. Main issue for SC is how to match between energy require and supply. Researchers are trying to find multiple solution from various aspects. Thirty SC prototypes were developed globally by numerous parties and most of them from academic bodies or universities. The purpose of the development is for solar car racing and to break commercialization boundary. As far as technology is concern, to achieve self-powered SC is quite challenging. The nearest potential solution can be learned from HC and PEV. All these potential solutions must be balance with the other side factor and come with a cost.

Drying process is one of the most common application used in solar thermal. This experiment was tested on performance of a large-scale solar dryer to dry natural fiber. The dryer consists of several main component such as solar thermal collector, heat exchangers and confine polycarbonate chamber. Average solar irradiance, ambient temperature and relative humidity recorded were612.84 W/m2, 32.42 oC and 60.01 %. The drying was completed in 3 days or 14.58 hours, and able to reduce 1004.2 kg weight and 70.7 % moisture content wet basis. Performance of the dryer was evaluated based on evaporative capacity, specific moisture extraction rate and specific energy consumption, and the values are 68.88 kg/hr, 3.55 kg/kWh and0.28 kWh/kg respectively. Cost of operation determined as RM117.13 per cycle and cost of product was RM0.28 for every kilogram dried fiber produced. Based on capital cost, annual return of investment and profit, payback period estimated is about 3.7 years.

Solar power is the third major renewable energy after hydropower and biopower. It constitutes an increasingly important element of the global future that is less carbon energy investment. However, the generation capacity, availability, and intermittency of this renewable energy source is strongly climate dependent. Therefore it makes this renewable energy supply system more vulnerable to climate variability and changes. When considering solar energy as a sustainable energy solution, it is important to not only quantify the present solar resource but to also anticipate how the solar resource as the indicator in electricity production potential will change under future climate change scenarios. In this study, we evaluate the climate change impact on solar photovoltaic (PV) power potential in Kota Kinabalu, a rapidly developing city in Malaysia, using the Weather Research Forecast Model (WRF) climate projections under RCP4.5 and RCP8.5 together with a PV Power Production Model (1MW). The projected median solar radiations were 193.6 Wm-2 and 211.9 Wm-2 in 2100 under RCP4.5 and RCP8.5 respectively. The changes in solar radiation were statiscally significant at 95% percentile for both climate scenarios. In comparison with the present day scenarios (181.8 Wm-2), the projected future mean solar radiations were also increased to 202.8 Wm-2 (RCP4.5) and 210.9 Wm-2 (RCP8.5), an increase of about 12% and 16% respectively. Results also indicated that the calculated annual average solar radiation for Kota Kinabalu at present-day and future scenarios were 1589.7 kWh/h2 (2014), 1773.4 kWh/h2 (2100-RCP4.5), and 1844.2 kWh/h2 (2100-RCP8.5), which are equivalent to 54.4 MW (2014), 60.7 MW (2100-RCP4.5), and 63.1 MW (2100- RCP8.5). Increases in energy production under future climate change scenarios show a promising trend and indicates a positive potential for solar energy to be harnessed in the Kota Kinabalu city area.

A spectrometer is likely to perform as expected over a period of time if calibrated with suitable method. This paper aims to study the variation of the Perez calibration algorithm over time for a spectrometer. The study was carried out for six months from July to August 2012 and January–April 2013. The measurements were recorded for every minute interval from 8.30 a.m. to 4.30 p.m. in three locations in Kota Kinabalu, Sabah, Malaysia. Monthly calibration constants for eight wavelengths were determined for the Perez model using improved Langley method. When only wavelengths which are close to 500 nm (460, 500, 540, 580, and 620 nm) were engaged, the variations over time of the Perez calibration constants were consistent over time (F = 1:381, p = 0:273). This is similar to the previous ?nding on the Du Mortier algorithm.

This paper presents the global solar radiation in UniversitI Malaysia Sabah, Kota Kinabalu, Sabah, Malaysia (6.0367°N, 116.1186°E) over period of one year from 2013 to 2014 using LI-200 pyronometer data logger set. Daily and monthly average global solar radiation values were calculated from 10 minutes average recorded values. Daily maximum global solar radiation were 1056.10 W/m2 was recorded on August 18, 2013 while the highest daily average global solar radiation of 495.90 W/m2 was recorded on August 28, 2013. Global solar radiation of Kota Kinabalu were compared to other cities in Malaysia. From the data collected we can see that Kota Kinabalu receive ample global solar radiation and has a very strong potential for solar energy development.

The paper presents the computer simulation of the improved prediction model in Part 1 and compared with the classical density model. The prediction model in Part 1 is improved by incorporating the effect of fluid dynamic viscosity when there are salinity and temperature differences between two fluids, for better prediction of kinetic power output. The viscosity prediction model takes account of the water head losing causing by frictional effect and viscous dissipation which in turns provides an analytical predicted outcome. Computer simulations are presented in this paper to assess the system as the parameters of system are varied using the Viscosity Model.

Salinity difference between fluids can be utilized and converted to useful power through an underwater hydroelectric power unit, Hydrocratic Generator. The generator system relies on the difference between the osmotic pressure of the incoming fresh water from on-ground reservoir, and the surrounding sea water in the system. In this investigation, additional parameter is introduced which is the temperature difference between fluids; hence the system is known as Ocean Salinity and Temperature Energy Conversion System (OSTEC). With the classical Density Model, there is over estimation of the predicted power output if compared to the experimental power output. Backward numerical extrapolation is performed on the experimental flow rate and found that the experimental water head of incoming water is significantly lower than the theoretical water head. This indicated that the experimental water head of incoming water does sustain a certain amount of head losing during the testing. As a consequence to minimize the prediction error, a refined prediction model is formulated by incorporating the effects of frictional head loss and head loss causing by the number of pipe fittings. Computer simulations are presented in this paper to assess the system as the parameters of system are varied using the refined prediction model.

The mixture between two fluids of different salinity has been proven to capable of producing electricity in an ocean salinity energy conversion system known as hydrocratic generator. The system relies on the difference between the salinity of the incoming fresh water and the surrounding sea water in the generator. In this investigation, additional parameter is introduced which is the temperature difference between the two fluids; hence the system is known as Ocean Salinity and Temperature Energy Conversion System (OSTEC). The investigation is divided into two papers. This first paper of Part 1 presents the theoretical formulation by considering the effect of fluid dynamic viscosity known as Viscosity Model and later compares with the conventional formulation which is Density Model. The dynamic viscosity model is used to predict the dynamic of the fluids in the system which in turns gives the analytical formulation of the potential power output that can be harvested.