Solar car: brief review and challenges

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

Prediction Model for the Performance of Different PV Modules Using Artificial Neural Networks

This study presents a prediction model for comparing the performance of six different photovoltaic (PV) modules using artificial neural networks (ANNs), with simple inputs for the model. Cell temperature (Tc), irradiance, fill factor (FF), short circuit current (Isc), open-circuit voltage (Voc), maximum power (Pm), and the product of Voc and Isc are the inputs of the neural networks’ processes. A Prova 1011 solar system analyzer was used to extract the datasets of IV curves for six different PV modules under test conditions. As for the result, the highest FF was the mono-crystalline with an average of 0.737, while the lowest was the CIGS module with an average of 0.66. As for efficiency, the most efficient was the mono-crystalline module with an average of 10.32%, while the least was the thin-film module with an average of 7.65%. It is noted that the thin-film and flexible mono-modules have similar performances. The results from the proposed model give a clear idea about the best and worst performances of the PV modules under test conditions. Comparing the prediction process with the real dataset for the PV modules, the prediction accuracy for the model has a mean absolute percentage error (MAPE) of 0.874%, with an average root mean square error (RMSE) and mean absolute deviation (MAD) of, respectively, 0.0638 A and 0.237 A. The accuracy of the proposed model proved its efficiency for predicting the performance of the six PV modules

Performance Analysis of a Double Pass Solar Air Thermal Collector with Porous Media Using Lava Rock

This paper investigates double-pass solar air thermal collectors with lava rock as the porous media. The addition of lava rock serves as short-term sensible thermal storage for a solar drying system. It also enhances the convective heat transfer rate to the airflow due to an increased heat transfer area and increased turbulence in the air channel. A mathematical model was developed based on energy balance equations and was numerically solved in MATLAB. The collector’s thermal performance was studied at various levels of solar intensity and at different wind speeds for different design parameters: collector size, air mass flow rate, and lava rock volume. From the study, the optimum efficiencies that were obtained in the range between the intensities of 500 W/m2 and 800 W/m2 were 62% to 64%, respectively, with an optimum flow rate of 0.035 kg/s. The optimum porosity of about 89% was selected for the collector by considering the pressure drop and thermal efficiency. An optimal temperature output range between 41.7 °C and 48.3 °C could be achieved and was suitable for agricultural and food drying applications. Meanwhile, compared to conventional DPSAHs, the average percentage increase in the output temperature of the DPSAH with lava rock was found to be higher by 17.5%

Incorporating theoretical and practical approaches to assess the amount of sunlight captured by a tilted surface in a tropical climate

Global solar radiation can theoretically be approximated in terms of tilt and azimuth of the surface regarding the impossibility of simultaneous measurement of solar radiation at various surface tilt and azimuth angles. Moreover, the random and anisotropic nature of diffuse radiation in a tropical climate makes it extremely difficult to estimate global solar radiation accurately as a function of surface tilt and azimuth angles. This study aims to develop a novel experimental and theoretical approach in the form of a computational network in order to determine a precise combined model integrated with global horizontal solar radiation to evaluate global tilted solar radiation in a tropical climate. Obtained results revealed that precisely estimation of the global tilted solar radiation was possible, by combining geometric factors for the tilted beam solar ra- diation, a combination of Gueymard and Louche models for the tilted diffuse solar radiation, and isotropic ground reflectance model for the ground reflected radiation, along with global horizontal solar radiation. It was observed that the accuracy of the model developed was higher for the partly sunny sky compared to the cloudy and rainy sky, estimates were more accurate on south-facing surfaces, and the model’s accuracy declined with the increasing tilt angle of the surface. The statistical analysis exhibited excellent agreement between the measured data and simulation results, considering the value of normalized mean absolute error (nMAE %), normalized root mean squared error (nRMSE %), and mean absolute percentage error (MAPE %), which were in the ranges 0.22–0.94, 0.27–1.11, and 0.23–1.02, respectively for estimating global tilted solar radiation in various regions of Peninsular Malaysia, and they were respectively found in the range of 10.2–27.5%, 16.1–38.9%, and 6.0–17.8%, for evaluating the monthly optimum tilt angle towards the south, that leads to a loss of solar energy from 1.3 to 5.

Solar Assisted Heat Pump System for High Quality Drying Applications: A Critical Review

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

Techno-economic analysis of a hybrid solar dryer with a vacuum tube collector for Hibiscus Cannabinus L Fiber

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, respectivel

Investigation of Potential of Solar Photovoltaic System as an Alternative Electric Supply on the Tropical Island of Mantanani Sabah Malaysia

This article reports on the potential use of a photovoltaic solar system on Mantanani Island. This island has its attractions in terms of flora and fauna as well as the uniqueness of its local community. The electricity supply status of the island is minimal, and the local electricity provider only provides two units of electrical generator that only supply energy from 18:00 to 06:00. This study is motivated by the hypothesis that if the target resident can obtain a better electricity supply, they can generate higher income and improve their standard of living. This study aims to identify the status of solar energy sources, estimate the basic electrical load, and conduct a techno-economic analysis of homestay enterprises of residents. Geostationary satellite data on solar energy resources were gathered and analyzed using Solargis. The electricity load was calculated based on the daily routine activities of the residents and usage of primary electrical appliances. Techno-economic analysis was done by determining the key parameters to calculate the return on investment and payback period. The results showed that Mantanani Island had great potential for implementing a photovoltaic system, by the estimated value of the total annual solar energy and peak sun hour of 1.447 MWh/m2/y and 4.05 h, respectively. The variation in total monthly solar energy was minimal, with a range of only 61.3 Wh/m2 . The calculated electrical load was 7.454 kWh/d. The technoeconomic assessment showed that the return on investment was MYR 3600 per year. However, the value of the payback period varies according to the value of the cost of capital spent. Regarding the cost of capital of this study, the shortest and longest payback periods achievable were 2.78 and 13.89 years, respectively. This calculation is in line with a photovoltaic system with a capacity of 2.2 kWp

Evaluation on moisture extraction of Malaysian spratelloides gracilis cracker by using heat pump dryer

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 Radiation Resources Under Climate Change Scenarios - A Case Study in Kota Kinabalu, Sabah, Malaysia

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