bluuebunny/crossref_metadata_2025 huggingface dataset:
Effect of in-situ carbon dioxide sorption on methane reforming by nickel-calcium composite catalyst for hydrogen production
Authors: Chen C H , Yu C T , Chen W H , Kuo H T
Published: April 2020

Hydrogen production plays an important role in hydrogen energy development. The steam reforming reaction is an efficiency way for hydrogen production via thermochemical method. But the hydrogen concentration was limited to be about 70% because of thermodynamic equilibrium. In order to avoid equilibrium limiting, the by-product CO2 removal during reaction was a suitable solution that drives the reaction to the right. In this study, the steam reforming of methane by in-situ CO2 sorption was investigated. The CaO material was used as CO2 acceptor because of its high capacity, fast kinetics and generality. The reforming catalysts were prepared by simple physical mixing of the 20 wt.% Ni/Al2O3 catalyst and CaO sorbents. The steam reforming of methane experiments was carried out by a fixed bed reactor. The experimental results indicate that the steam reforming of methane via in-situ CO2 sorption obviously obtained the H2 purity above 95% higher than conventional reaction without in-situ CO2 removal (~72% H2). The impurities involving CO and CO2 during reaction were suppressed below 0.5% before CO2 sorbent saturation. In this work, the highest H2 purity and CH4 conversion were founded to be 98.4% and 95% at 873K under steam/carbon ratio of four conditions. The methane steam reforming with high conversion strongly depended on the CO2 capture performance. The cause was attributed to the equilibrium limiting of reaction overcoming by in-situ CO2 sorption. It is also found that the product components and methane conversion was insignificantly affected in the range of space velocity from 7200 to 19200 cm3/hr/g.
First principles investigation on the nitrogen-doped planar aluminene for hydrogen storage application
Authors: Pedrosa G R , Villagracia A R , Bayasen D S , Lin H , Ong H L , David M , Arboleda N
Published: April 2020

With the rise of carbon emission daily, a pursuit for cleaner energy such as hydrogen fuel is necessary. Obtaining a good hydrogen storage is one of the main bottleneck to achieve a working hydrogen economy. Materials including two-dimensional systems have been widely investigated for potential hydrogen storage. In this work, the effects of nitrogen on the hydrogen adsorption on planar hexagonal aluminene was studied using density functional theory. Aluminene was decorated with nitrogen at different sites: top, hollow and bridge. Results showed that nitrogen was adsorbed at the top, bridge and hollow sites at a distance of 0.00Å to 1.80 Å with binding energies of 2.71 eV, 4.88 eV, and 3.44 eV, respectively. Comparing to the pristine aluminene, there was no major difference with its electronic and magnetic properties based on the density of states of the nitrogen-doped aluminene while the nitrogen atom gained some charges from the aluminium atoms based on the charge difference. On the other hand, a hydrogen molecule was adsorbed with binding energies ranging from 13.4meV to 26.3 meV close enough to the adatom on the decorated system. Minimal broadening of energy level was found from the density of states. This work shows that aluminene with nitrogen impurity can adsorb hydrogen molecules. However, high concentration of nitrogen will lower the hydrogen capacity of aluminene.
Density functional theory investigation on hydrogen adsorption on buckled aluminene
Authors: Villagracia A R , Ong H L
Published: April 2020

Hydrogen storage is one of the challenging components in hydrogen economy towards a cleaner energy. Two-dimensional materials are being explored as a potential hydrogen storage material. Adsorption of hydrogen on buckled aluminene was investigated using first principles with the incorporation of van der Waals correction via Tkatchenko-Scheffler method. Four possible adsorption sites were identified: top of the first layer, bridge, hollow, and top of the lowest layer. Critical results of energy calculations showed that hydrogen molecule can be physisorped on any sites of buckled aluminene with a binding energy of 0.77 eV without additional energy needed to store it. This physisorption is demonstrated in the density of states showing a slight broadening of energies. Hydrogen would prefer to be adsorbed as a molecule due to a dissociation barrier of 3.23 eV to recover the hydrogen. Another critical finding is that buckled aluminene has more possible hydrogen adsorption sites and higher binding energy than that of planar aluminene indicating a better candidate as a potential hydrogen storage material at a higher ambient temperature.
Suppression of hydrodynamic sloshing in liquefied natural gas tank with floating baffle: Experimental and numerical studies
Authors: Md Arif Ummul Ghafir , Loo Ching-Yun , Kang Hooi-Siang , Punurai Wonsiri , Quen Lee Kee , Lai Gavin Nai-Yeen , Chong Wen-Tong
Published: April 2020

A fixed anti-sloshing mechanism such as baffles which modifies the tank structure may lead to increment of the maintenance cost. This paper proposes a floating baffle, and reviews its investigation on the sloshing behaviour in a membrane-type tank model under unidirectional excitation with 30% and 50% of filling ratio. An LNG tank was numerically simulated in OpenFOAM under regular sinusoidal motion with an amplitude of 3 cm and excitation frequency set to the natural frequency at 1.1 seconds. Impulsive pressure on the tank wall was obtained, and then benchmarked with the experimental results from the pressure sensors. The simulation and experiment results showed an acceptable agreement with a root mean squared error of less than 10%. The findings are expected to become a significant reference for safer sea transportations such as conventional LNG vessels.
Effects of aquifer on heat exchange process in geothermal applications
Authors: Ma Zhendi , Jia Guosheng , Kong Qiongxiang , Xia Zhenhua , Jin Liwen , Meng Xiangzhao
Published: April 2020

Geothermal energy has been widely used in the field of the building heating through the ground heat exchanger (GHE). The groundwater flow in the aquifer is one of the significant factors affecting the heat exchange process between the GHE and ground by promoting the pure conduction to the conjugated convection and conduction heat transfer. In this paper, the variations of the ground temperature field and the thermal influence radii subject to the existence of aquifers were investigated numerically. The geometrical models consisting of a coaxial heat exchanger, multiple aquifer and aquifuge layers were established to study the effect of groundwater velocities and the number of aquifer layers on the GHE system. The results reveal that the heat exchange capacity of the GHE is enhanced when the groundwater velocity increases. The increased number of aquifer layers can also enhance the heat exchange capacity with the tested groundwater velocity at 315 m/a or 31.5 m/a, but would weaken it with the velocity of 3.15 m/a. In addition, it is found that the aquifuge temperature field is affected by the aquifer layer, and the thermal influence radius of GHE is dominated by the groudwater velocity of aquifers when the velocity is larger than the critical velocity. Conversely, the thermal influence radius is governed by the thermal diffusivities of aquifuges for the groundwater velocity samller than the critical velocity.
Experimental validation and improvement of actuator line model in the large-eddy simulation of wind-turbine wakes
Authors: Gao Zhi-Teng , Wang Tong-Guang
Published: April 2020

Wind-turbine wakes significantly affect the power output of downstream wind turbines. In order to improve the calculation accuracy of wind-turbine wakes in the atmospheric boundary layer, a new improved actuator line - large-eddy simulation (AL-LES) method is proposed and verified by experiments. The traditional AL-LES method is improved in three aspects. Firstly, the atmospheric turbulence is generated by a dynamic k-equation LES with a wall shear stress model and a buoyancy effect model. Secondly, the nacelle and tower are modelled based on the static actuator line method. Finally, the distribution of blade body force is improved by using an anisotropic 3D Gaussian function. Based on the results of three wind tunnel experiments conducted by Norwegian University of Science and Technology (NTNU), China Aerodynamics Research and Development Centre (CARDC) and Von Karman Institute for Fluid Dynamics (VKI), the improved AL-LES method is validated from the aspects of wind-turbine power performance, the generation of tip vortex, and the distribution of wake velocity under typical offshore and onshore conditions. In addition, a full-scale wind turbine installed in Gansu is used for the experimental and numerical research. The main conclusion is that compared with the traditional method, the new AL-LES method improves the numerical accuracy by nearly 22%, and can more accurately simulate the interaction between atmospheric turbulence and wind-turbine wakes. The results can help the research of wind-turbine wakes and the micro-location selection of wind farm.
On the performance of melting features in a thermal energy storage unit: metal foam argumentation
Authors: Yang Xiaohu , Niu Zhaoyang , Yu Jiabang , Liu Gang , Wang Xuanbo , Zhao Mengyu , Yu Xiyang
Published: April 2020

Thermal energy storage has been attracting more and more attentions due mainly to its distinctive features on peak-load shifting capability for systems with renewable energy involved. To further improve the overall thermal efficiency for charging/discharging processes, heat transfer techniques to enhance phase change heat transfer are typically employed. This paper introduced a novel concept of partially-filling ratio of metal foam into PCM. The melting heat transfer can be expected to be further enhanced with partially filled metal foams. To this aim, an axisymmetric two-dimensional computational model was established. A series of numerical simulations were carried out to study the effect of filling ratio of metal foam on the melting performance of a TES tube. Good agreement was achieved through the comparison of temperatures obtained from simulation and experimental measurements. Based on the results, it can be concluded as follows: if the goal was to enhance heat transfer simultaneously to save material cost, the suggested filling ratio was 0.90; if saving material cost was the aim, the filling ratio can be further reduced to 0.85. The proposed novel TES unit with partially-filled metal foam outperformed other competing heat transfer technique.
Three-phase five level diode clamped inverter for AC load interfacing in DC Microgrid
Authors: Win Soe , Linn Zarchi
Published: April 2020

In this paper, diode clamped type three-phase five-level inverter is used for AC load interfacing in DC microgrid. Multilevel inverters generate staircase voltage waveform with a series of power semiconductor switches from several layer voltage DC sources. Therefore, the output voltage waveforms in multilevel inverters can be generated at low switching frequency with high efficiency and low distortion. In two-level inverter, various pulse width modulation (PWM) strategies with high switching frequency is required to obtain a output voltage or a current waveform with a small amount of harmonic content. In existing DC microgrid, three-phase conventional two-level Sine-PWM inverter is used and so, total harmonic distortion (THD) is high. To reduce the THD and the size of AC filter and to get the quality output, diode clamped type three-phase five-level inverter is applied in this research. Level shift multi carrier Sine-PWM method is used for the diode clamped circuit topology. The output waveforms of conventional two-level inverter and diode clamped five-level inverter are measured and compared the each output waveform qualities such as voltage THD, current THD and AC filter size. The performance of five level diode clamped inverter is illustrated by PSIM software and experimental results are carried out with prototype.
Smart solar photovoltaic panel cleaning system
Authors: Khadka Nasib , Bista Aayush , Adhikari Binamra , Shrestha Ashish , Bista Diwakar
Published: April 2020

With the increasing demand for renewable energy, solar photovoltaic technology is being a topic of concern. However, due to the accumulation of dust and dirt over the panel surface, the performance of the photovoltaic system degrades to a noticeable number. To address this issue: a fully automated, cost worthy and efficient system needs to be invented. This paper presents the design and fabrication process of a prototype able to clean the panel surface. The prototype of this system comprises of a cleaning robot and a cloud interface: the cleaning robot is mobile and able to clean the entire solar array back and forth, with its separately driven cleaning rotatory brush; whereas, the cloud interface is a human-machine interface featuring the distant monitoring and control of the robot. Additionally, to notify the performance of distantly placed solar farm, a sensing unit consisting of sensors was added to this system. Furthermore, to add an automatic cleaning feature, a month-long data of totally clean and dusty panel was processed with regression analysis, and the developed regression model was programmed into the sensing unit. The sensing unit added with the regression model is named as an autonomous unit, as it predicts the suitable time for cleaning action. According to the system evaluation done on a demonstration PV module, it was found that the designed system can clean dry dust accumulated over the panel’s surface. Moreover, by attaching the metal rail tracks on a long solar array, the system seems to be implementable on a large scale solar farm.
Effect of surfactants on thermal conductivity of graphene based hybrid nanofluid
Authors: Hong W.X. , Sidik N.A.C. , Saidur R.
Published: April 2020

Various hybrid nanofluids have been researched in this decade. The quality of this said-to-be alternate heat transfer medium depends on two major features – long term stability and high thermal conductivity. In recent years, graphene-based nanofluid was reported to exhibit distinguished heat transfer performance compared to most materials investigated in past studies. This study aims to compare the effect of different surfactants on thermal conductivity of graphene-based nanofluid. Sodium dodecylbenzenesulfonate (SDBS) and hexadecyltrimethylammonium bromide (CTAB) were mixed separately in advance with the mixture of water and ethylene glycol. After mixing surfactants and base fluid, total 0.025 to 0.1 wt% of nanoparticles were added into the mixture and followed by ultrasonication. Mono nanofluid was produced by adding graphene nanoplatelets (GnP) only whereas a novel hybrid combination was composed of graphene nanoplatelets and titanium dioxide. Stability of each sample was inspected using zeta potential analysis and Uv-vis spectroscopy. Thermal conductivity of samples from 30 °C to 60 °C was measured using Decagon KD2 Pro. Both surfactants contributed to high zeta potential value and minimal sedimentation for all nanofluids. CTAB improved the thermal conductivity of hybrid nanofluid more compared to SDBS, with 11.72% difference at 0.1 wt% nanoparticles concentration when compared to base fluid at 60 °C. The highest enhancement (23.74%) on base fluid was spotted at 60 °C, where 0.1 wt% of GnP was mixed with CTAB. These findings could strengthen literature on suitable surfactant to be used on graphene based nanofluid since limited comparison work has been done. High thermal conductivity of the hybrid nanofluid at high temperature could be used as coolant in cooling system.
Business model and market designs for solar prosumer on peer to peer energy trading in Thailand
Authors: Kokchang P. , Junlakarn S , Audomvongseree K.
Published: April 2020

In recent years the power system is undergoing a rapid change from the traditional power system with large-scale power plants to small-scale distributed generations such as wind energy and solar photovoltaic system. In addition, the technology related to the electric business has been developed rapidly, such as solar power development technology, energy storage, and various communication and measurement devices, etc. The development of these technologies together with the reduced cost of technologies is the main factor in the transformation of the electric business model in many countries around the world, including Thailand to the way that electricity users turn from being consumers only to be both consumers and producers of electricity or called as prosumers. Also, it drives to the new paradigm: peer-to-peer electricity trading, where consumers and prosumers can buy or sell electricity locally. However, the concept of peer to peer energy trading is at early stage in Thailand. This study points out the benefits and barriers of peer to peer energy market based on reviewed existing peer to peer energy projects worldwide. The results of study show that the major regulatory barriers that restrictive to peer to peer market in most countries are the licensed energy supplier issue, network charging and no excess generation is fed back into the national grid.
Numerical investigation on melting of various nanoparticles enhanced phase change material inside a square enclosure
Authors: Kean Tung Hao , Che Sidik Nor Azwadi
Published: April 2020

In this paper, the numerical simulation on melting of phase change material was run by using ANSYS Workbench 17.0 that included mesh generation tools and FLUENT software. Paraffin wax was selected as the PCM and three types of nanoparticles: Alumina (Al2O3), Copper oxide (CuO) and Zinc Oxide (ZnO) were added to form nanoparticles enhanced phase change material. This paper focus on the melting rate and energy stored of phase change material in a 100mm × 100mm square enclosure. The effect of heat source orientation and the mass fraction of nanoparticles dispersed in phase change material were also investigated. Enthalpy porosity method was applied in this numerical study. Results shown that melting rate only can improved by adding low volume fraction of nanoparticles (2% wt). The overall melting rate of phase change material heated from the vertical side is higher than that heated from below. Besides, the energy Stored during the melting of phase change material heated from vertical side is greater and faster compared with heated from bottom. Al2O3 was the best enhancing nanomaterial among those three nanoparticles as it shown the fastest melting rate and highest amount of energy stored (207287 J).
A review on preparation of nanocellulose for new green working fluid in heat transfer application
Authors: Bin Harun Muhammad Arif , Che Sidik Nor Azwadi
Published: April 2020

Cellulose is one of the sustainable raw materials and natural polymers as it can be abundantly found in biomass products. Nanocellulose consist of three categories which are bacterial nanocellulose (BNC), cellulose nanofibrils (CNF), and cellulose nanocrystalline (CNC) has the potential to be used for working fluid in heat transfer application with nanofluid characteristics. Nanofluid is defined as a fluid that has nanoparticle dispersed in it. This nanoparticle will enhance the thermophysical properties of the base fluid. Many types of nanofluid have been used widely in heat transfer applications such as Al2O3, TiO2, CuO and CNT but only a few studies had been done using green and environmentally friendly materials. Therefore, nanocellulose is one of the best candidates as one of the nanofluid’s materials which has green and environmentally friendly properties. The preparation of nanofluid is very crucial because improper preparation will lead to deterioration of nanofluid and decrease the thermal performance as heat transfer working fluid. Other than that, low stability cause nanoparticle to form clusters and sediment due to its strong van der Waals interaction. Therefore, this study will focus on the preparation method of the nanocellulose for heat transfer application. Other than that, methods of stability analysis for nanocellulose also presented in this paper.
Comparison between simulations and experiment for heat transfer characteristics in the re-burning kiln heat exchanger
Authors: Panyoyai Piyathida , Tantikul Samerkhwan , Wongsiriamnuay Thanasit , Khamdaeng Tipapon , Tippayawong Nakorn , Panyoyai Numpon
Published: April 2020

Waste heat from the combustion process that is left unused may cause pollution problems and adversely affect health. This waste heat should be recovered. In this research, the simulation and experimental data on heat transfer characteristics of the pipe coiled inside the re-burning kiln heat exchanger were studied. The main objective of this study was to compare heat transfer coefficients obtained from the simulation using water as the working fluid with those obtained experimentally from the re-burning kiln heat exchanger for the drying system. The re-burning kiln heat exchanger was of coil-pipe-type with an outside diameter of 38 mm. The coiled pipe set up on the re-burning kiln heat exchanger was 80 cm in width and 173 cm in height. The flow rate of the cold water used as a working fluid was varied from 10 to 20 LPM, while the surface temperature of the coil pipe was varied from 200±20°C to 400±20°C, respectively. Thermal conductivity and outlet temperature of the water were also measured as a function of the internal temperature and water flow rate. The experimental results were validated against the simulation. The results showed that when the flow rate of water inlet decreased from 20 LPM to 10 LPM, the temperature of the water outlet was increased from 52.4 °C to 76.3 °C respectively. An increase in the temperature of the water outlet because of increased the re-burning kiln heat exchanger temperature and reduced the mass flow rate of supply water. The obtained simulated heat transfer coefficient in the re-burning kiln heat exchanger was in agreement with the experimental results.
Role of solar energy for enhancing sustainable energy and electricity in Myanmar: An outlook
Authors: Lin Ohn Zin , Mon Khine Khine , Htay Tin Tin
Published: April 2020

Sustainable Energy Development is a must consideration for energy sector. Energy Trilemma index is quite low in Myanmar as only 40% of the country is electrified At 66% of Final Energy Consumption, the residential sector was the largest energy consumer, due to the use of fuel wood for cooking. For electricity sector, load shedding problems are frequently occurred in dry season because of insufficient generation. Local peoples are also protesting Coal fired power plants and natural gas is also not available sufficiently. In this paper, the role of solar energy to enhance energy security, affordability and environmental sustainability are analyzed using energy Trilemma index as a tool. Energy Trilemma is used as a tool to determine the sustainability development of the energy sector. According to the analysis, three indices of energy trilemma can be improved by solar energy and it is a vital role for sustainable energy development in Myanmar.
Influence of operational and economic factors on the optimal design of an electric vehicle battery cooling system
Authors: Gundran Julius Ezra M. , Culaba Alvin B. , Ubando Aristotle T.
Published: April 2020

Electric vehicles are a leading alternative to traditional vehicles. However, high expenditure on battery replacement due to rapid capacity loss limits their market penetration. Given that the high temperatures reached during operation greatly contribute to capacity loss, battery cooling systems are often necessary to extend battery life. In designing a cooling system, lifetime cost is a crucial consideration as both capital expenditure and battery replacement cost savings are associated with the system. To extend the prior initial study, this study investigates the influence of various factors on the economically optimal design. Similar to the initial study, the investigated case is that of a typical electric jeepney in Manila, Philippines. Existing models for the electrothermal and aging behavior of the battery, thermal behavior of the cooling system, and capital costs of the cooling system components are linked to form a system simulation. The simulation, implemented in Simulink is coupled with a genetic algorithm implementation in MATLAB to generate the optimal cooling system design. As with the initial study, air and phase change material are the cooling media considered. Given their significant expected influence on the optimal design, the following factors are investigated: drive cycle, ambient temperatures, and component capital costs. The results of this study agree with the preliminary study. The optimization results do not favor air cooling in any case investigated; none of the cases justify its high capital and operating costs. Phase change material (PCM) cooling is also unfavored in all cases, save for that using the US06 drive cycle, showing that only extreme temperature rise due to high current draw can justify investment in PCM cooling. Although previous studies have found that lowering battery temperature extends battery life, this study reveals that the capital and operating costs of battery cooling systems are still a hurdle to be overcome.
Comparative customer economics on different financial options in support the adoption of residential rooftop photovoltaic in Thailand
Authors: Junlakarn S , Kokchang P
Published: April 2020

The Thai Government has supported the use of solar photovoltaic systems for green electricity production toward the self-consumption policy since 2016. A photovoltaic support program with an installed capacity target of 100 Megawatt was announced in December 2018 to promote self-consumption and compensate for any excess photovoltaic generation at 1.68 Thai Baht/kilowatt-hour. However, the target was not achieved as a result of high upfront investment costs that are one of the main barriers in household application. To make solar photovoltaic systems more accessible to a larger group of users, financial mechanisms are required. The economic feasibility of financial options (cash, solar power purchasing agreement, solar leasing, solar loan) was analyzed for photovoltaic systems under the current Thai household solar rooftop scheme. The System Advisor Model, an open source techno-economic analysis tool, was employed to simulate photovoltaic production and cash flows to calculate the economic feasibility including the levelized cost of electricity, net present value, internal rate of return and payback period. Results showed that investment in a 3-kilowatt photovoltaic system with debt fraction of 50% and 100% cash was profitable, while investment in a 3-kilowatt photovoltaic system through a solar power purchasing agreement and leasing was not economically viable.
Optimum planning of a renewable energy based hybrid mini-grid system for embracing the sustainability benefits in southern Myanmar
Authors: Ya Aung Ze , Thar Hla Aye , Win Yee Yee , Moe Khin Moe , Myint Kay Khaing , Win Sein May Thu
Published: April 2020

This article reveals the Optimization of the Renewable Energy based Hybrid Mini-grid system to energize a village Kyein Ne Taung with 645 households. The feasibility of the project is analysed in HOMER (Hybrid Optimization of Multiple Energy Resources) Pro. The site visit is carried out in July, 2019. The architecture of the proposed model comprises 160 kW PV System, 160 kW Wind System, 1320 kWh Battery Storage System, and 123 kW Converter. Regarding the current situation, the proposed Hybrid system can terminate 4500 tons per year and 2600 $ per year for Fuel wood cooking as well as 7000 litres per year and 8000 $ per year for Diesel fuel applications. By comparing with the Diesel Mini-grid to electrify the desired scenario, the proposed planning can save Diesel fuel 132,567 liters per year, Diesel fuel cost 132,567 $ per year, as well as reduce the GHG (Greenhouse Gas) emissions, including Carbon Dioxide 347,009 kg per year, Carbon Monoxide 2,187 kg per year, Unburned Hydrocarbons 95.4 kg per year, Particular Matter 13.3 kg per year, Sulfur Dioxide 850 kg per year, and Nitrogen Oxides 2,055 kg per year. Therefore, simulated results prove the available Sustainability benefits, and the reliable performance of the proposed system. This research can be useful as the reference of the affordable and modern Energy planning for other Coastal villages in Southern Myanmar.
Performance analysis of maximum power point tracking control system for standalone wind power system in Sittwe, Myanmar
Authors: Win Yee Yee , Ya Aung Ze , Thar Hla Aye , Phyu Aye MyatKyi , Myint Kay Khaing , Win Sein May Thu
Published: April 2020

One of the most feasible Renewable Energy resources of the World is wind energy. The performance of the Maximum Power Point Tracking (MPPT) control system for the operation of the Standalone Wind Power generation system is studied in this research. Sittwe, the capital of Rakhine State in Western Coastal Region, is the chosen case study area that enriches the Wind Energy resources in Myanmar with the low electrification rate. The proposed Standalone Wind Power generation system is composed of three-phase, 20kW Permanent Magnet Synchronous Generator (PMSG), DC-DC bidirectional converter, switch mode rectifier, voltage source inverter, and three-phase load. It is modelled and simulated in the MATLAB/Simulink. The simulation period is set to 15 seconds. Under Wind speed variation from 3 m/s to 13 m/s, the investigation is performed with the nexus of the speed, torque, power, DC link input, DC link output, and the parameters of the load side. In the simulation results, the power characteristics show the 20 kW standalone wind power system. It is observed that the output load voltage can be controlled by load side converter to required load voltage. In addition, the simulation results reflect the dynamic performance can be improved with the proposed MPPT control system.
An outlook on large-scale solar power production in Peninsular Malaysia for scenario year 2030
Authors: Cheong Kuen Hou , Tai Vin Cent , Tan Yong Chai , Abd Rahman Nor Faiza , Chiong Kai Shing , Saw Lip Huat
Published: April 2020

Traditional power generation mix lacks renewable energy (RE) sources to cover fast depletion of fossil fuel. Malaysia is picking up on solar energy with the aim of enhancing the national power generation mix by reducing the dependency on fossil fuel and thus mitigate the greenhouse gas (GHG) emissions. However, integration of large amount of solar power may pose a challenge to power system planning and operation. This paper therefore, attempts to present an outlook on large-scale solar (LSS) in Peninsular Malaysia for scenario year 2030, with objective to serve a guideline for future power planning by adopting the optimum penetration of LSS. Firstly, total optimal potential areas (OPA) for LSS power production in Peninsular Malaysia are determined based on several important geometry factors. Next, its corresponding technical potentials include energy generation potential (EGP), installation capacity (IC) and annual carbon dioxide emission reduction (CO2 ER) are reported. Three hypothetical studies of solar penetration: 5%, 10% and 15% are demonstrated and subsequently compare with national electricity consumption forecast 2030. Peninsular Malaysia has enormous potential for LSS power production as reflected from total OPA of 10,092 km2. With only 10% of solar penetration (206,691 GWh/yr), it is sufficient to cover national energy demand, forecast to be 134,642 GWh/yr. This positive finding is very encouraging to reveal the significant potential of LSS in national energy mix. It will give a much-needed boost to the country RE sector and a robust growth is envisaged.
Feasibility study of polypropylene-based aluminium-air battery
Authors: Naqiuddin Nor Haziq , Saw Lip Huat , Yew Ming Chian , Chong Wen Tong , Chen Wei-Hsin , Poon Hiew Mun , Yew Ming Kun
Published: April 2020

The global economy depend on the fossil fuel to meet the daily power demands, ranging from electricity supply to transportation. It is estimated that more than 60% of the world power generation is depending on the fossil fuel. Therefore, the search for clean energy to replace fossil fuel has become the current research trend in the world. Metal-air battery featuring high energy density is projected as one of the promising candidate for the next generation energy storage system. There are various type of metal-air batteries available in the literature such as lithium-air battery, magnesium-air battery, silicon-air battery, aluminium-air battery, zinc-air battery, etc. However, aluminium-air batteries with its low cost and high energy density of 4300 Wh/kg show a great potential for future energy storage applications. In this study, the performance of the aluminium-air battery with polypropylene separator is being investigated. The battery is filled with 1M of Potassium Hydroxide electrolyte. Anode of the battery is made of Aluminium foil and carbon fibre cloth is used as cathode of the battery. The experimental results shown that, the maximum capacity of 23 mAh can be achieved using 6.25 mA of constant current discharge. By connecting the batteries in series, it is sufficient to power on a light-emitting diodes and charging a mobile phone.
Intelligent optimization of process conditions for maximum metal recovery from spent zinc-manganese batteries
Authors: Ruhatiya C , Tibrewala Himanshu , Gao Liang , Sleesongsom Suwin , Chin C M M
Published: April 2020

By 2025, 2 million metric tons of batteries must be recycled. Among these batteries, the spent Zinc-Manganese batteries poses a serious threat to environment due to toxic heavy metals. This metals are toxic but at same time vital for various industrial applications. This metals are generally recovered by physical-chemical process which are highly energy intensive and polluting. An eco-friendly recycling process has to be explored to tackle such issue. The bioleaching is one such eco-friendly recycling method. The objective of this work is to optimize the process parameters of bioleaching method, so as to make this process commercially viable. The optimization of this process is done through statistical based automated neural network intelligent optimization approach. The formulated models were inline with the complex behaviour of bioleaching process. The training and validation performance of the models were near to 1. The parametric, global sensitivity and interaction analysis was undertaken for understanding the relationship between different parameters and its affect on the metal yield. The optimum values of process parameters were determined for maximizing the metal yield.
Hydrodynamic sloshing of microalgae in membrane type photobioreactor
Authors: Khor Wei-Han , Kang Hooi-Siang , Quen Lee Kee , Jiang Xiaoxia , Ng Cheng-Yee , Tan Lit-Ken , Tang Collin Howe-Hing
Published: April 2020

The tropical climate, wide diversity of microalgae species, long coastline, abundant sources of agriculture effluent, and active phycology research are key factors that drives Malaysia to be highly competitive in the global microalgae market. Microalgae are vital in a variety of applications such as: biofuel, health foods, agricultural feeds and chemical extractions. However, mass cultivation of microalgae is still not cost effective in Malaysia due to huge energy consumption Therefore, cultivation of microalgae that utilizes wide ocean space and wave energy for mixing has gained interest since it has considerably lower production cost. Nonetheless, the effects of ocean wave-induced sloshing in terms of its efficiency of mixing have not been fully researched. Thus, this study has been conducted to investigate the effects of sloshing hydrodynamics in microalgae cultivation by studying the interactions of sloshing hydrodynamics and mixing efficiency inside a floating photobioreactor. A membrane type photobioreactor has been used to slosh microalgae culture on its free surface. The result of mixing efficiency for suspended solid particles in liquid is the main concern. Experiments in unidirectional excitation proven that mixing rate of solid-liquid medium is dependent on the excitation amplitude, excitation frequency and filling ratio, where mixing rate is highest at 30% filling ratio with increasing excitation amplitude and excitation frequency. With deeper comprehension on the interaction effects of sloshing hydrodynamics and mixing efficiency, upscaling of novel microalgae cultivation method in industrial size can be expected.
Energy-cost-aware flow-shop scheduling systems with state-dependent energy consumptions
Authors: Aghelinejad Mohammad Mohsen , Ouazene Yassine , Yalaoui Alice
Published: April 2020

The necessity of managing a production system with less cost and pollution in such a competitive world has enticed the attention of many researchers. This paper deals with a multi-state two-machine flow-shop scheduling problem under Time-Of-Use electricity tariffs. The main issue is to assign a set of jobs to available time slots with different energy costs to minimize the total energy consumption costs. For this purpose, a new linear programming (LP) model is proposed, and several numerical results are solved using CPLEX Studio 12.9.0 solver to evaluate the effciency of the proposed model for the problem. The obtained results demonstrate that CPLEX solver is not able to find the optimal solution for the problems as large as 20 jobs and 90 periods during the 3600 seconds time limitation.
A product arrangement optimization method to reduce packaging environmental impacts
Authors: Truong C.T.T. , Amodeo L. , Yalaoui F. , Hautefaye J.C. , Birebent S.
Published: April 2020

The Three-dimensional Open Dimension Rectangular Packing Problem (3D-ODRPP) is one of the most important optimization problems arise in reducing waste and shipping cost of packing and shipping industries. The 3D-ODRPP aims at seeking the length, width and height of a rectangular box of minimal volume that can pack a given rectangular products. Most 3D-ODRPP models in the literature use too many extra binary variables and don’t consider the equilibrium of product placement. This study presents an improved mathematical model for the 3D-ODRPP. The proposed model uses fewer decision variables and constraints to define product orientation. It also adopts the full base support (FBS) constraint as a product supporting condition to guarantee packaging stability and avoid infeasible arrangements. Literature instance tests show the improvement in packaging stability of the proposed method compared with existing methods. Industrial benchmark demonstrates that, by solving the 3D-ODRPP, the proposed method can reduce package volume and create economic and ecologic gains.
A systemic approach to integrated sustainable solid waste management through community engagement: A case study of Tan Deaw sub-district, Saraburi province
Authors: Sridan Pornpod , Surapolchai Pichaya
Published: April 2020

The recent residue solid waste management has become a significant global concern. Due to the increase of population, the economic growth and the urban expansion, the number of solid waste has heavily risen. However, there are still lack of an appropriated solid waste management. According to Tan Deaw soild waste survey report in 2019 (Regional Environmental Office 7 Saraburi, 2018), it revealed that Tan Deaw sub-district has been facing critical solid waste management issues. This area produced 9.41 metric tons per day, while the appropriated solid waste disposal management was less than 40 percent and residue waste remains around 2,000 MTs. Therefore, the objectives of this research are to develop learning community and public awareness towards the appropriated solid waste disposal management, including 3Rs principle, to develop the systemic solid waste management strategies with the engagement from all stakeholders, and to promote and support collaborative activities among local people in the community and the concerned stakeholders in the solid waste management. A systemic approach, through participatory action research between Soft Systems Methodology (SSM) (Checkland & Scholes, 1990; Checkland & Poulter, 2006) and Critical Systems Heuristic (CSH) (Ulrich, 1983), is a significant application for structuring the process of collecting perspective from all stakeholders, exploring the key problems of solid waste management, and finding out strategies to address the key problems in Tan-Deaw solid waste management afterwards. Root definitions and models were generated by stakeholders for two activity systems identified by them for attention: Activities promoting knowledge about solid waste sorting and a community waste bank. The findings explored the seven strategies to address Tan-Deaw solid waste management problems in two aspects. This research contributes to both theoretical and practical contributions. In terms of the theoretical contribution, the application of systemic approach conducts a significant knowledge surrounding solid waste management problem solving. Regarding the practical implication, the strategies will address the solid waste problems and barriers in the area with the cooperation of all concerned stakeholders.
The impact of El Niño-southern oscillation to the wind and solar data in Malaysia
Authors: Albani A. , Ibrahim M.Z. , Ghani S. , Zulkifli M.R. , Ganesan N.N.A.G.
Published: April 2020

Malaysia has initiated initiatives to use renewable energy as a resource of electricity generation since 2011 through the establishment of laws and policies related to renewable energy. The geographical location of Malaysia has led to limited of intermittent renewable energy resources and requires a more detailed study of the various factors impacting electricity generation. This paper aims to understand the impact of El Niño-Southern Oscillation (ENSO) events on the reanalysis wind and solar data. The Wavelet Transform will be used to study the relationship between the reanalysis wind and solar dataset with the Multivariate ENSO index in the Malaysia region. During Very Strong and Strong El Nino, the site experienced an increment of both wind velocity and solar irradiance and reduced during La-Nina. This ENSO impact study is essential as a reference for future wind and solar energy development planning, energy predicting, and risk valuation in Malaysia.
Evaluating the effect of different biochar application sizes on methane emission reduction from rice cultivation
Authors: Sriphirom P , Chidthaisong A , Yagi K , Boonapatcharoen N , Tripetchkul S , Towprayoon S
Published: April 2020

Application of biochar to the soil has been reported as one of the mitigation technologies of CH4 emission from rice cultivation due to its unique characteristics of high porosity and surface area. The application of small particle size of biochar is rich in surface area that may enhance the mitigation potential. Rice cultivation and soil incubation experiments were conducted to evaluate the effect of two groups of biochar particle size on CH4 emission and production in order to show the mitigation potential. This experiment consists of three treatments including no biochar (CT), small particle size (0.5-2 mm) biochar (SB), and large particle size (2-4 mm) biochar (LB). Both biochar sizes were amended at 10 t ha−1 equivalent rate and all treatments were applied chemical fertilizer at 100 kg N ha−1 equivalent rate. The results demonstrated that SB and LB reduced cumulative CH4 emission by 24.0% and 17.1% and cumulative CH4 production by 24.6% and 15.0% as compared to CT, respectively. Our results showed that SB achieved higher mitigation potential than LB by an average of 8.47%, although it was not significant. The mitigation of both biochar sizes was supported by the significant change of soil methanogens and methanotrophs abundances. The suppression of methanogens abundance and the stimulation of methanotrophs abundance indicated in the ratio of mcrA to pmoA was significantly reduced in SB (68.0%) which higher than in LB (56.3%) as compared to CT. Both application sizes also increased soil oxidation capacity through soil Eh increase which no difference between SB and LB. In term of grain yield, SB and LB were not different and both did not show the significant change as relative to CT. The application of small size biochar in this study affected more mitigation potential of CH4 emission as compared to larger size, therefore there is a need of further study on typical size of biochar in order to recommend the most mitigation potential of biochar application.
A fluid-structure interaction modelling of roof mounted renewable energy installations in low rise buildings for extreme weather and typhoon resilience
Authors: Jay Pantua Conrad Allan , Calautit John Kaiser , Wu Yupeng
Published: April 2020

Super typhoon Haiyan made landfall in the Philippines last 2013 where an estimated 1.1 million homes were damaged. There was massive roofing damage in the houses due to strong winds. With the increasing number of roof-mounted renewable energy installations, there is a clear need to review the current systems to respond to future climactic events. The current approach for building performance analysis under typhoon wind loads involves a lot of wind tunnel tests, full scale testing and finite element modelling which is heavily reliant on wind tunnel data which are costly and time consuming. Current renewable energy mounting technologies with its different installation methods, and mounting locations consequently affected by wind loads differently. Using the proposed framework, this study evaluated solar panels attached to the gabled roof of a single detached low-rise building. The stress and deformation of the structure and the panels was determined using the typhoon’s Atmospheric Boundary Layer flow simulation. Building energy simulation was used to determine the appropriate site orientation to maximise solar energy generation. Results show areas of high failure rate in the panels in the 0 degree wind angle direction and in the panels closer to the edge. Maximum solar energy generation was determined at the 90 degree site orientation.
Effect of fire flame exposure on basalt and carbon fiber reinforced concrete
Authors: Abd Razak Siti Nooriza , Shafiq Nasir , Azmi Yasmin Mohd , Guillaumat Laurent , Farhan Syed Ahmad , Ayesha Wan Farra , Grampeix Guillaume
Published: April 2020

Concrete in general is a poor conductor of heat, but it can suffer significant damage when exposed to fire. Investigation of concrete behaviour when exposed to fire has generated interest where most of the fire cases take place in buildings and tunnels. Incorporation of fiber in concrete can improve the mechanical performance as it acts as crack arresters, resisting the development of cracks, hence making the concrete composite matrix stronger. In this study, mechanical behaviour of basalt and carbon fiber reinforced concrete for different characteristic strengths at 28 days were investigated for its performance when exposed to fire flame. Fire flame test using methane gas was developed to simulate real fire phenomena. Concrete specimens were subjected to fire flame at the temperature of 1000 °C for a period of 90 minutes. Visual observation (colour change, cracking and spalling), loss of density and residual compressive strength of the concrete specimens were performed. The results obtained were compared with reference specimens. Test results showed that tested samples experienced cracking and spalling, reduction of mass and compressive strength. All samples experienced compressive strength loss except for G20 OPC which recovers 7.8 % compressive strength. Addition of carbon fiber showed an increased in strength before exposure compared to basalt fiber. Minor damages were observed for carbon fiber in concrete after fire exposure compared to basalt fiber.