International Journal of Renewable Energy Development

Journal Information
ISSN / EISSN : 22524940 / 22524940
Current Publisher: Diponegoro University (10.14710)
Total articles ≅ 233
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Ibrahim Mahariq, Svetlana Beryozkina, Huda Mohammed, Hamza Kurt
International Journal of Renewable Energy Development, Volume 9, pp 1-6; doi:10.14710/ijred.9.1.1-6

Abstract:The existence of magnetic field around high-voltage overhead transmission lines or low-voltage distribution lines is a known fact and well-studied in the literature. However, the interaction of this magnetic field either with transmission or distribution towers has not been investigated. Noteworthy it is to remember that this field is time-varying with a frequency of 50 Hz or 60 Hz depending on the country. In this paper, we studied for the first time the eddy currents in towers which are made of metals. As the geometrical structures of towers are extremely complex to model, we provide a simple approach based on principles of electromagnetism in order to verify the existence of power loss in the form of eddy currents. The frequency-domain finite difference method is adapted in the current study for simulating the proposed model. The importance of such a study is the addition of a new type of power loss to the power network due to the fact that some towers are made of relatively conductive materials.©2020. CBIORE-IJRED. All rights reserved
Mahfud Mahfud, Ummu Kalsum, Viqhi Ashwie
International Journal of Renewable Energy Development, Volume 9, pp 113-117; doi:10.14710/ijred.9.1.113-117

Abstract:Aim of this research are to study and develop research related to the potential of Chlorella sp. into biodiesel with the help of microwaves in-situ transesterification by characterizing parameters such as microwave power (300; 450; 600 W) and reaction time (10; 30; 50 minutes) with catalyst concentration of KOH and molar ratio of microalga : methanol are 2% and 1:12 respectively and optimized by response surface methodology with Face Centered Central Composite Design (FCCCD). The study was carried out by dissolving the catalyst into methanol according to the variable which was then put into a reactor containing microalgae powder in the microwave and turned on according to the predetermined variable. After the reaction process is complete, the mixture is filtered and resuspended with methanol for 10 minutes to remove the remaining FAME and then the obtained filtrate is cooled. Water is added to the filtrate solution to facilitate the separation of hydrophilic components before being separated and pushed apart until 3 layers are formed. Amount of FAMEs in the first layer formed were extracted with n-hexane solution and washed with water and the FAME product obtained was then distilled to remove the remaining n hexane and then weighed. The results indicated that yield increased with increasing reaction time and microwave power with the best conditions of 50 minutes each and 440.53 watts with the highest yield reaching 35.72% (dry basis) through using of KOH catalysts with low concentrations, 2%.©2020. CBIORE-IJRED. All rights reserved
Maya Sarah, Hisham Hisham, Mushila Rizki, Ricka Erwinda
International Journal of Renewable Energy Development, Volume 9, pp 125-130; doi:10.14710/ijred.9.1.125-130

Abstract:Investigation on microwave technique to extract pectin from cocoa pod husk in this study carries out using citric acid and hydrochloric acid (HCl). Extraction proceeds at various microwave powers (180, 300, 450, 600 Watt) and irradiation periods (10, 15, 20, 25, 30 minutes). This study observed effect of power and time to yield and quality of pectin. Yield of pectin increased at elevated power and time either with citric acid or HCl solvent. Overall pectin quality in this study meet the IPPA quality factor exclude water content which relatively higher. MAE treatment with citric acid using microwave power of 300 Watt for 30 minutes resulted yield of 42% and high pectin quality as compare to MAE treatment with HCl. The best pectin product in this study has moisture content of 8%, ash content of 10%, equivalent weight of 714.29 mg, methoxyl content of 4.8% and galacturonate level of 43%. ©2020. CBIORE-IJRED. All rights reserved
Mohammed Ayad Alkhafaji, Yunus Uzun
International Journal of Renewable Energy Development, Volume 9, pp 69-76; doi:10.14710/ijred.9.1.69-76

Abstract:In recent years, the variable speed motor drive is supported over a fixed speed motor drive as per essentialness safeguarding, speed or position control and improvement of transient response characteristics. The aim of any speed controller is to take main signal that represent the reference speed and to drive the framework at that reference speed. This paper exhibits the design, simulation and control of synchronous reluctance motor (SynRM). In addition, the motor speed is controlled by utilizing a conventional PID controller that has been used from the cascaded structure. The Particle Swarm Optimization (PSO) was used to find the best parameters of the PID controller. Lead-Lag controller presents from the cascaded controller as the following period of control. The Space vector pulse width modulation (SVPWM) plot has been proposed to control the motor and make the motor work with no rotor confine contingent upon the info parameters that utilization in the simulation. An examination between both of PID tuned and PSO tuned controller affirms that the PSO gives dazzling control highlights to the motor speed and have an edge over the physically changing controller. Thus, this paper present investigation and simulation for the most precise procedures to control the speed reaction and torque reaction of synchronous reluctance motor (SynRM).©2020. CBIORE-IJRED. All rights reserved
Mohammad Zainul Abidin, Haula Rosdiana, Roy Valiant Salomo
International Journal of Renewable Energy Development, Volume 9, pp 53-62; doi:10.14710/ijred.9.1.53-62

Abstract:This paper examines tax incentive policies in geothermal industries in ASEAN to better understand the development of geothermal industry investment in the ASEAN Member States (AMS) using a qualitative method. The results indicate that tax incentive policies have supported the investment climate and the development of geothermal industries in the AMS. Geothermal investments and production capacities in AMS have increased significantly. AMS that provide geothermal tax incentives include Indonesia, Lao PDR, the Philippines, Thailand and Vietnam. The performance of geothermal tax incentive policies is reflected in the level of utilization of geothermal potential, which is higher in states that provide greater tax incentives. The results also indicate that geothermal power plants in AMS use dry steam, flash and binary cycle technologies with flash plants being the most common. Results suggest that the future development of geothermal energy in AMS will be related to the tax incentive policy and investment climate in those states. Furthermore, the granting of various types of tax incentives should be focused on the initial investment in geothermal development. ©2020. CBIORE-IJRED. All rights reserved
H Hadiyanto, Apsari Puspita Aini, Widayat Widayat, Kusmiyati Kusmiyati, Arief Budiman, Achmad Roesyadi
International Journal of Renewable Energy Development, Volume 9, pp 119-123; doi:10.14710/ijred.9.1.119-123

Abstract:Biodiesel can be produced from various vegetable oils and animal fat. Abundant sources of vegetable oil in Indonesia, such as Calophyllum inophyllum, Ricinus communis, palm oil, and waste cooking oil, were used as raw materials. Multi-feedstock biodiesel was used to increase the flexibility operation of biodiesel production. This study was conducted to determine the effect of a combination of vegetable oils on biodiesel characteristics. Degumming and two steps of esterification were applied for high free fatty acid feedstock before trans-esterification in combination with other vegetable oils. Potassium hydroxide was used as a homogenous catalyst and methanol as another raw material. The acid value of C. inophyllum decreased from 54 mg KOH/gr oil to 2.15 mg KOH/gr oil after two steps of esterification. Biodiesel yield from multi-feedstock was 87.926% with a methanol-to-oil molar ratio of 6:1, temperature of 60 ℃, and catalyst of 1%wt. ©2020. CBIORE-IJRED. All rights reserved
Damgou Mani Kongnine, Pali Kpelou, N’Gissa Attah, Saboilliè Kombate, Essowè Mouzou, Gnande Djeteli, Kossi Napo
International Journal of Renewable Energy Development, Volume 9, pp 29-35; doi:10.14710/ijred.9.1.29-35

Abstract:This work was focused on carbonizing four tropical fruits shells wastes such as: coconut shells (CS), palmyra shells (PS), doum palm shells (DPS), whole fruit of doum palm (WFDP) and teak wood (TW) used as control. The aim was to investigate the potential of those biochar to be used as an alternative energy source in replacement ofcharcoal. The raw biomasses samples were carbonized under the same conditions and some combustion characteristics of the obtained biochar such as lower calorific value, energy per unit volume associated to bulk density, ash content, moisture content and ash mineral content were investigated. The temperature in the furnace was estimated during carbonization process using a K-type thermocouple. The thermal profile of the studied raw biomasses reveals three phases of carbonization. The biochar yield drops significantly for all biomasses as the final maximum temperature increases. The average yields obtained ranged from 37.81 % for palmyra shells to 27.57 % for the doum palm shells. The highest yield achieved was 42.32 % obtained at 280 °C for palmyra shells, the lowest yield (24.42 %) was recorded at the highest maximum temperature of 590 ° C for doum palm shells. The results of energy parameters of the studied biochar showed that coconut shells charcoal presented the highest lower calorific value (28.059, followed by doum palm shells (26.929 when, with 25.864, whole fruit of doum palm charcoal showed the lowest lower calorific value. Similarly, with the highest bulk density of 0.625 g/cm3 coconut shells charcoal presented the highest energy per unit volume (17536.88 J/cm3), whereas with the lowest bulk density of 0.415 g/cm3, whole fruit of doum palm charcoal presented the lowest energy per unit volume. The ash content analysis showed that whole fruit of doum palm had the highest ash content (18.75 %) and palmyra nut shells charcoal (8.42 %).Teak wood charcoal, took as control, has the highest lower calorific value (32.163, less dense as coconut shell (0.43 g/cm3), his energy per unit of volume is 13830.09 j/cm3 but the lowest value of as content (2.90 %). Among these biomasses charcoals, only whole fruit of doum palm charcoal ash showed a high chloride and sulfide content respectively 9.73 % and 1.75 % in weight. From these results, the produced charcoals could be used as alternative fuels except for whole fruits of doum palm charcoal which chloride and sulfide content were found high. ©2020. CBIORE-IJRED. All rights reserved
Somayeh Pahlavan, Mehdi Jahangiri, Akbar Alidadi Shamsabadi, Alireza Baharizadeh
International Journal of Renewable Energy Development, Volume 9, pp 97-105; doi:10.14710/ijred.9.1.97-105

Abstract:Innovative and more sustainable methods of supplying energy needs in the world have led to a change in the dependency model for fossil fuels, including more integrated planning and adoption of new and motivating models regarding the use of renewable energy. Today, with the reduction of fossil fuel consumption in the world, the use of renewable energy has gained an important role in the global energy mix, but according to studies, the share of renewable energy in Iran’s energy mix is very small. Therefore, the present paper attempts to present all potentialities for obtaining clean energy in Iran by assessing the current state of renewable energies. The fact that, in the present time, the real value of energy carriers is not appreciated properly in Iran, on the one hand, and the lack of willingness to invest in these energies in the private sector, which may have been less protected, on the other hand, has caused the consumption level of fossil fuels to remain unchanged, which may have some disadvantages, such as environmental damage, in addition to their utilization. The authors of the paper are of the opinion that, on the one hand, by finding solutions for bank investment problems, easing restrictive laws, providing bank with guarantees by investors, as well as modifying parts of the guaranteed electricity purchase contract for accepting foreign banks to provide loans and obtain financing, and on the other hand, by facilitating the process of obtaining land permits and connecting to these power plants, Iran is not far from reaching a reasonable rank in the world.©2020. CBIORE-IJRED. All rights reserved
Suherman Suherman, Hasri Widuri, Shelyn Patricia, Evan Eduard Susanto, Raafi Jaya Sutrisna
International Journal of Renewable Energy Development, Volume 9, pp 131-139; doi:10.14710/ijred.9.1.131-139

Abstract:In this study, hybrid solar drying of coffee beans was performed, and energy analysis was carried out, to assess the system’s performance, in terms of energy efficiency, compared to solar drying and the open sun drying method. The dryer has three compartments: solar collector for collecting solar radiation, drying chamber, and a Liquid Petroleum Gas burner, which acted as an auxiliary heater to assist the thermal energy. The drying chamber has four trays for placing the dried product. The initial moisture content of coffee beans was 54.23% w.b and was reduced to the final moisture content between 11-12% w.b. The coffee beans dried faster when subjected to the solar hybrid drying method, compared to other methods, with the dryer temperature of 40°C, 50°C, and 60°C. Results indicated that the coffee beans’ drying times varied from 10 to 14 hours. However, at temperature 50°C and 60°C for the 1st tray, the water content was reduced more rapidly compared to the other tray. From the results of this study, we can see the different efficiency of solar collector that shows of 54.15% at variable temperature 60°C for drying time 12:00 to 14:00 p.m for hybrid solar drying and for the solar drying process is 50.07% at the range of drying time 12:00 to 14:00 p.m. Mathematical modelling shows that Page model is the most suitable for describing the coffee beans’ drying behaviour using a hybrid solar dryer. The effective diffusivity values found in this experiment are all in the acceptable range for most agricultural products. ©2020. CBIORE-IJRED. All rights reserved
I. Istadi, Teguh Riyanto, Luqman Buchori, Didi Dwi Anggoro, Roni Ade Saputra, Theobroma Guntur Muhamad
International Journal of Renewable Energy Development, Volume 9, pp 107-112; doi:10.14710/ijred.9.1.107-112

Abstract:Plasma-assisted catalytic cracking is an attractive method for producing biofuels from vegetable oil. This paper studied the effect of reactor temperature on the performance of plasma-assisted catalytic cracking of palm oil into biofuels. The cracking process was conducted in a Dielectric Barrier Discharge (DBD)-type plasma reactor with the presence of spent RFCC catalyst. The reactor temperature was varied at 400, 450, and 500 ºC. The liquid fuel product was analyzed using a gas chromatography-mass spectrometry (GC-MS) to determine the compositions. Result showed that the presenceof plasma and catalytic role can enhance the reactor performance so that the selectivity of the short-chain hydrocarbon produced increases. The selectivity of gasoline, kerosene, and diesel range fuels over the plasma-catalytic reactor were 16.43%, 52.74% and 21.25%, respectively, while the selectivity of gasoline, kerosene and diesel range fuels over a conventional fixed bed reactor was 12.07%, 39.07%, and 45.11%, respectively. The increasing reactor temperature led to enhanced catalytic role of cracking reaction,particularly directing the reaction to the shorter hydrocarbon range. The reactor temperature dependence on the liquid product components distribution over the plasma-catalytic reactor was also studied. The aromatic and oxygenated compounds increased with the reactor temperature.©2020. CBIORE-IJRED. All rights reserved