A study on temperature, relative humidity, and energy consumption in long-distance trains air conditioning systems in Indonesia Fathurrahman Yudhi, Muhammad Idrus Alhamid, Nandy Putra, Arnas Lubis Case Studies in Thermal Engineering, 2025 Trains are efficient and cost-effective means of public transportation capable of carrying large groups of passengers. The Heating, Ventilation, and Air Conditioning (HVAC) system, a significant component with substantial energy usage in train operations, often encounters issues due to problems with the HVAC system failing to provide comfortable air quality, ultimately impacting passenger satisfaction and posing concerns for operators. A significant disparity in understanding of HVAC systems on Indonesian trains is frequently observed in tropical regions, where ensuring good air quality, stable temperatures, and controlled relative humidity levels over extended periods poses unique challenges due to the typically hot and humid climate characterized by high external temperatures and fluctuating humidity levels. Therefore, this study aimed to evaluate the ability of HVAC systems to maintain temperature and humidity in trains. Temperature and humidity were measured during the journey at various areas in passenger compartments in three executive class intercity trains, covering both day and night conditions. The results showed that maintaining a consistent level of thermal comfort parameters throughout the journey was challenging for HVAC systems. Data suggests that temperature fluctuations took place during the daytime, whereas relative humidity (R.H) levels in the night and early morning rose to 28.2 °C and 81.2 % respectively, surpassing the established standards ISO 19659–2 of 27 °C for temperature and 65 % percent for relative humidity. These results were expected to guide the improvement of future HVAC systems designs, enhancing their ability to maintain consistent temperature under varying conditions. Additionally, the designs would focus on better humidity control through the incorporation of a reheating process in air supply, ensuring consistency of long-distance journey.
A waste heat recovery biomass salt cookstove for enhancing product quality, dewatering performance, economic aspects, and CO2 emission reduction Nizar Amir, Ibnu Irawan, Misri Gozan, Muhammad Idrus Alhamid International Journal of Ambient Energy, 2025 The salt recrystallization process in biomass salt cookstoves emits waste heat and CO2, both of which contribute to environmental degradation. Here, we developed an integrated waste heat recovery system in the biomass salt cookstoves that captures excess heat through a heat exchanger and generates hot air to support the salt dewatering process. Salt quality (as defined in SNI 3556:2016), dewatering performance, economic factors, and CO2 emission reduction were evaluated. This improved system produced dried salt that appeared as a white, fine powder with 1.06% moisture content, 97.14% NaCl, 0.115% Mg, 0.078% Ca, and no detectable heavy metals. Furthermore, the dewatering rate and moisture ratio improved, reaching 72.76%/min and 0.16, respectively. A comparative analysis demonstrated that replacing the electrical hot air generator with a waste heat recovery system in the improved cookstove reduced specific energy consumption, dewatering cost, and CO2 emissions by more than 80%. Thus, the results of this study offer a sustainable technology for salt production by micro, small, and medium-sized enterprises (MSMEs), with the potential to increase their income, facilitate the integration of environmentally sound technologies into government policy frameworks, and mitigate climate impacts through reduced thermal waste and CO2 emissions.
Building Stock and Emission Models for Jakarta Hanif Hanif, Ahmed Z. Khan, Muhammad Idrus Alhamid, Yohei Yamaguchi Resilient Cities and Structures, 2024 • Jakarta’s building sector has grown steadily, with a projected floor stock of 268 km 2 by 2050, up from 167 km 2 in 2010. • Operational emissions in Jakarta are more significant than embodied emissions, with landed houses being the primary contributors to both types. • The ministerial regulation on green building has successfully avoided building emission increases; however, to achieve net-zero emissions by 2050, ongoing regulatory advancements coupled with carbon offset project initiatives are essential. Understanding urban-scale building emissions is crucial for achieving net-zero targets. This study examined embodied and operational emissions in Jakarta from 2010 to 2022 using the bottom-up Building Stock Model (BSM) and analyzed building stocks across seven categories: apartments, offices, malls, hotels, education facilities, hospitals, and landed houses. Carbon factors for construction materials, fuels, electricity, and cooking gas, along with occupancy rates, were included in the emissions calculations. The findings reveal consistent growth in apartments, malls, and offices, with operational emissions significantly decreasing after the 2015 green building regulations. Despite a declining share in Jakarta’s building stock, landed houses still account for over 40% of embodied and nearly 75% of operational emissions. With around 80% of the population preferring to live in landed houses, their impact on emissions remains substantial. In 2010, Jakarta’s building floor stock was 167 km 2 . Projections using simple linear regression suggest it could reach 268 km 2 by 2050. Emission forecasts using the Prophet Forecasting Model (PFM) suggest that by 2050, building emissions could return to 2010 levels if stricter regulations are consistently enforced. The study underscores the necessity for continuous regulatory advancements and carbon offset initiatives to achieve net-zero emissions.
Modeling and Experimental Approach of an Organic Rankine Cycle Using a Scroll Expander Dwika Budianto, Cahyadi, Budi Ismoyo, Arnas Lubis, M. Idrus Alhamid Evergreen, 2024 : Recently, there has been a notable increase in focus on the organic Rankine cycle (ORC) progress. The system has remarkable abilities in the application of low-temperature and sustainable energy. This study examines the energy assessment of a hermetic scroll expander in an ORC. The chosen organic working fluid was R134a. Thermal oil served as an organic fluid in the heat source system, while an electric heater functioned as a heat supply. The thermal oil temperature was kept constant in this study at 65 o C. The study used a preliminary EES model and an experiment to evaluate the achievement of ORC in terms of power output and thermal efficiency. Certain modifications were made in EES concerning the heat supply and condensation temperature to predict the amount of power output and thermal efficiency. Based on the simulation result at this condition, we obtained a power output of 0.580 kWth with a net thermal efficiency of 2.9%. The results of the experiment demonstrate a power output of 0.381 kWth, 0.113 kWe of electric power, and a net thermal efficiency of 3.08%. The deviation between the simulation and experimental results was 4.87% for net thermal efficiency and 12.75% for turbine power output. The validation of the ORC model is based on the performance of the provided ORC prototype. Finally, the numerical model is used to investigate potential improvements for the prototype.
Development of Key Components for 5 kW Ammonia–Water Absorption Chiller with Air-Cooled Absorber and Condenser Desy Agung, Gabriel Garcia Genta, Arnas Lubis, M. Idrus Alhamid, Nasruddin Nasruddin Energies, 2024 An absorption chiller is an alternative cooling system that operates using heat from renewable energy sources and employs environmentally friendly working fluids, such as ammonia–water or lithium bromide–water. Given Indonesia’s high solar energy potential, solar cooling systems using absorption chillers are particularly promising. Solar thermal energy has been demonstrated to effectively power absorption chiller systems through both simulations and experiments. In Indonesia, there is significant potential to utilize small-capacity solar absorption chillers for buildings, particularly those employing air-cooled condensers and absorbers, which can reduce operational and maintenance costs. This research aimed to design a prototype of a 5 kW solar-assisted ammonia–water absorption chiller system specifically for residential applications. The system will be air-cooled to minimize space requirements compared to traditional water-cooled systems. The study addressed the design and specifications of the system’s components, dimensional considerations, and an analysis of the impact of the measurement instrument on the research outcomes. The results provide precise dimensions and specifications for the system components, offering a reference for the development of more advanced systems in the future.
Exergy, exergoeconomic and exergoenvironment analysis of heat pump system using environmentally friendly working fluid ECOS 2020 Proceedings of the 33rd International Conference on Efficiency Cost Optimization Simulation and Environmental Impact of Energy Systems, 2020
Parametric study and multi-objective optimization of vapor compression heat pump system by using environmental friendly refrigerant Journal of Advanced Research in Fluid Mechanics and Thermal Sciences, 2019
Exergy and energy analysis of a cascade refrigeration system using R744+R170 for low temperature applications International Journal of Mechanical and Mechanics Engineering, 2010
Techno-Economic Assessment of Ozonation in Open Cooling Towers A Lubis, BN Manalu, MH Fadillah, AFA Arrazaq, RR Prasetyo, N Giannetti, ... International Journal of Refrigeration, 106919 , 2026 2026
A waste heat recovery biomass salt cookstove for enhancing product quality, dewatering performance, economic aspects, and CO 2 emission reduction N Amir, I Irawan, M Gozan, MI Alhamid International Journal of Ambient Energy 46 (1), 2556772 , 2025 2025
Pathways to net zero: Scenario analyses of urban building stocks in Jakarta H Hanif, AZ Khan, MI Alhamid, Y Yamaguchi Energy and Buildings, 116919 , 2025 2025 Citations: 1
Thermodynamic and electrical output analysis of a small-scale organic Rankine cycle using R134a and a hermetic scroll expander D Budianto, A Lubis, MI Alhamid, II Hakim, M Aziz Energy Conversion and Management 344, 120278 , 2025 2025 Citations: 5
Development and performance evaluation of a novel industrial-scale fixed bed dryer for alkali-treated eucheuma cottonii chips N Amir, M Gozan, MK Aroua, MI Alhamid Sustainable Energy Technologies and Assessments 81, 104453 , 2025 2025 Citations: 2
A study on temperature, relative humidity, and energy consumption in long-distance trains air conditioning systems in Indonesia F Yudhi, MI Alhamid, N Putra, A Lubis Case Studies in Thermal Engineering 71, 106122 , 2025 2025 Citations: 8
The special issue of ENERGY-The International Journal dedicated to the 7th International Conference on Polygeneration (ICP-2023) LM Serra, JC Bruno, MI Alhamid Energy , 2025 2025
Experimental and simulation investigation of a Savonius vertical axis wind turbine for residential applications: a case study in Indonesia MY Efendi, N Amir, T Prasetyo, MYA Ramadhan, M Gozan, ... International Journal of Ambient Energy 45 (1), 2331231 , 2024 2024 Citations: 16
Building Stock and Emission Models for Jakarta H Hanif, AZ Khan, MI Alhamid, Y Yamaguchi Resilient Cities and Structures 3 (4), 63-82 , 2024 2024 Citations: 8
Analysis of thermodynamic simulation of small-scale organic rankine cycle (ORC) through utilization of low grade temperature geothermal plants D Budianto, B Ismoyo, Cahyadi, T Hidayat, MI Alhamid, A Lubis AIP Conference Proceedings 3090 (1), 090001 , 2024 2024 Citations: 1
Development of Key Components for 5 kW Ammonia–Water Absorption Chiller with Air-Cooled Absorber and Condenser D Agung, GG Genta, A Lubis, MI Alhamid, N Nasruddin Energies 17 (17), 4376 , 2024 2024 Citations: 2
Design and analysis of a 20-feet modular cold storage system MA Budiyanto, O Imamudien, MI Alhamid, T Shinoda Thermal Science and Engineering Progress 50, 102587 , 2024 2024 Citations: 4
The impact of wettability on the performance of a two row wavy fin and tube liquid desiccant system for dehumidification and regeneration W Indrawan, A Lubis, MI Alhamid Applied Thermal Engineering 241, 122387 , 2024 2024 Citations: 6
Simultaneous adsorption of multicomponent lanthanide ions on pectin encapsulated zeolite A E Kusrini, MI Alhamid, DA Wulandari, M Fatkhurrahman, EWES Shahrin, ... Evergreen 11 (1), 371-378 , 2024 2024 Citations: 7
The design of psychrometric chamber control system at University of Indonesia J Surya, AS Yatim, MI Alhamid, EP Wijaya, S Nandiwardhana, ARA Bahar AIP Conference Proceedings 2710 (1), 030009 , 2024 2024
Comparative Analysis of the Performance of the Thermal Pasteurization System Using Ohmic Heating Method with an Electric Heater on Mango Puree W Wardika, F Sugara, MI Alhamid, A Ardiyansyah International Journal Applied Technology Research 5 (1), 43-53 , 2024 2024
Simultaneous Adsorption of Multicomponent Lanthanide Ions on Pectin Encapsulated Zeolite A K Eny, MI Alhamid, DA Wulandari, F Mufiid, EWES Shahrin, NNM Shahri, ... Evergreen 11 (1), 371-378 , 2024 2024
Studi Eksperimental Kinerja Sistem Organic Rankine Cycle 2 kW Scroll Ekspander dengan Fluida Kerja R134a Pada Sumber Panas Temperatur Rendah MI Alhamida, A Lubisa, II Hakima, D Budiantoa, B Riset Seminar Nasional Tahunan Teknik Mesin XXII 2024, 233-243 , 2024 2024 Citations: 1
Modeling and Experimental Approach of an Organic Rankine Cycle Using a Scroll Expander D Budianto, B Ismoyo, A Lubis Transdisciplinary Research and Education Center for Green Technologies … , 2024 2024 Citations: 1
Top-Down Model and Holt-Winters Method for Building Stocks and Emissions in Jakarta H Hanif, AZ Khan, MI Alhamid, Y Yamaguchi 2023
MOST CITED SCHOLAR PUBLICATIONS
Potential of geothermal energy for electricity generation in Indonesia: A review MI Alhamid, Y Daud, A Surachman, A Sugiyono, HB Aditya, TMI Mahlia Renewable and Sustainable Energy Reviews 53, 733-740 , 2016 2016 Citations: 285
Synthesis, characterization, and performance of graphene oxide and phosphorylated graphene oxide as additive in water-based drilling fluids E Kusrini, F Oktavianto, A Usman, DP Mawarni, MI Alhamid Applied Surface Science 506, 145005 , 2020 2020 Citations: 101
Solar-assisted single-double-effect absorption chiller for use in Asian tropical climates A Lubis, J Jeong, K Saito, N Giannetti, H Yabase, MI Alhamid Renewable energy 99, 825-835 , 2016 2016 Citations: 94
Enhancement of thermal comfort in a large space building HM Kamar, NB Kamsah, FA Ghaleb, MI Alhamid Alexandria Engineering Journal 58 (1), 49-65 , 2019 2019 Citations: 80
Energy and exergy analysis of an R410A small vapor compression system retrofitted with R290 TKB Fajar, PR Bagas, S Ukhi, MI Alhamid, A Lubis Case Studies in Thermal Engineering 21, 100671 , 2020 2020 Citations: 66
Operation performance enhancement of single-double-effect absorption chiller A Lubis, J Jeong, N Giannetti, S Yamaguchi, K Saito, H Yabase, ... Applied energy 219, 299-311 , 2018 2018 Citations: 62
Dynamic optimization of chilled water pump operation to reduce HVAC energy consumption TK Wijaya, MI Alhamid, K Saito, N Nasruddin Thermal Science and Engineering Progress 36, 101512 , 2022 2022 Citations: 51
Design of a solar AC system including a PCM storage for sustainable resorts in tropical region N Putra, P Estellé, I Alhamid, N Abdallah, A Yatim, T Maré, AL Tiffonnet, ... Evergreen 6 (2), 143-148 , 2019 2019 Citations: 47
Operation strategy of a solar-gas fired single/double effect absorption chiller for space cooling in Indonesia MI Alhamid, A Coronas, A Lubis, DS Ayou, K Saito, H Yabase Applied Thermal Engineering 178, 115524 , 2020 2020 Citations: 36
Adsorption Isotherms of CH 4 on Activated Carbon from Indonesian Low Grade Coal A Martin, WS Loh, KA Rahman, K Thu, B Surayawan, MI Alhamid, ... Journal of Chemical & Engineering Data 56 (3), 361-367 , 2011 2011 Citations: 36
Hot water temperature prediction using a dynamic neural network for absorption chiller application in Indonesia MI Alhamid, K Saito Sustainable Energy Technologies and Assessments 30, 114-120 , 2018 2018 Citations: 35
Solar absorption chiller performance prediction based on the selection of principal component analysis N Aisyah, MI Alhamid, BB Saha, S Sholahudin, A Lubis Case Studies in Thermal Engineering 13, 100391 , 2019 2019 Citations: 33
Effect of polypropylene plastic waste as co-feeding for production of pyrolysis oil from palm empty fruit bunches E Kusrini, D Supramono, IA Muhammad, S Pranata, DL Wilson, A Usman Green Asia Education Center 6 (1), 92-97 , 2019 2019 Citations: 33
Impacts of temperature on airborne particles in a hospital operating room N Kamsah, HM Kamar, MI Alhamid, KY Wong Journal of Advanced Research in Fluid Mechanics and Thermal Sciences 44 (1 … , 2018 2018 Citations: 31
Thermodynamic and environmental analysis of a high-temperature heat pump using HCFO-1224yd (Z) and HCFO-1233zd (E) MI Alhamid, N Aisyah, N Nasruddin, A Lubis International Journal of Technology 10 (8), 1585 , 2019 2019 Citations: 30
Simultaneous adsorption of multi-lanthanides from aqueous silica sand solution using pectin–activated carbon composite E Kusrini, MI Alhamid, AB Widiantoro, NZA Daud, A Usman Arabian Journal for Science and Engineering 45 (9), 7219-7230 , 2020 2020 Citations: 27
Refrigeration cycle exergy-based analysis of hydrocarbon (r600a) refrigerant for optimization of household refrigerator MI Alhamid, N Nasruddin, E Susanto, TF Vickary, MA Budiyanto Green Asia Education Center 6 (1), 71-77 , 2019 2019 Citations: 19
Numerical simulation of a two-bed solar-driven Adsorption chiller in a tropical climate MI Alhamid International Journal of Technology 6 (4), 594-603 , 2015 2015 Citations: 19
Chiller performance study with refrigerant R290 Z Fuadi, A Yatim, R Rizky, N Aisyah, I Alhamid, B Budihardjo, N Putra AIP Conference Proceedings 2062 (1), 020061 , 2019 2019 Citations: 18
Adsorption isotherms of hydrogen on granular activated carbon derived from coal and derived from coconut shell Nasruddin, A Martin, MI Alhamid, D Tampubolon Heat Transfer Engineering 38 (4), 403-408 , 2017 2017 Citations: 18