Low-Cost Energy Management Strategies for a Commercial Biodiesel Plant in Malaysia: A Case Study Based on Industrial Operation and Aspen Plus Simulation
This study investigates low- and no-capital energy management strategies for a commercial 500-metric-ton-per-day biodiesel plant located within a Malaysian oleochemical complex in the Klang Valley. Drawing on several years of industrial operating experience and a validated Aspen Plus V10 steady-state process simulation, the work provides a comprehensive mass- and energy-balance assessment under typical operating conditions, with particular emphasis on the first five years of plant operation. The simulation model was validated against more than ten steady-state plant operating cases collected over a one-year period following commissioning, demonstrating good agreement with plant operating data. The baseline process was found to have a specific energy consumption of approximately 200 kWh per metric ton of oil input under an oil-to-methanol ratio of 1:5. Unlike most existing studies, which focus on capital-intensive measures such as waste-gas recovery, steam-network optimization, and heat-exchanger retrofits, this case study concentrates on operational and process-engineering levers—including methanol feed-ratio optimization, reflux stream management, and improved production planning and scheduling—to reduce fuel consumption without requiring plant modifications. The analysis showed that reducing the oil-to-methanol ratio from 1:5 to 1:4.5 reduced process energy consumption by 7.6% while maintaining a biodiesel conversion of 98.5% and meeting EN 14214 biodiesel quality requirements. By integrating real plant data with simulation-based energy-stream analysis, the study delivers actionable, low-cost energy management measures that can be readily adopted by Malaysian biodiesel producers to improve energy efficiency, reduce CO2 emissions, and support business viability in an export-oriented, subsidy-influenced fuel market, while also identifying waste-heat recovery without capital expenditure as a key area for future research.
References
[1]
Jalil, A. (2026) Malaysia to Kick Off B15 Roll Out in 19 Plants in June. New Strait Times (NST). https://www.nst.com.my/business/economy/2026/05/1432398/malaysia-kick-b15-rollout-19-plants-june-watch?source=widget
[2]
MPOB (2025) Overview of the Malaysian Oil Palm Industry in 2025. https://bepi.mpob.gov.my/images/overview/Overview2025.pdf
[3]
Agri-Commodity Pocket Stats (APS) (2026) Published and Printed by Ministry of Plantation and Commodities. https://www.kpk.gov.my https://heyzine.com/flip-book/pocket-stats-q4-2025.html#page/46
[4]
Islam Rony, Z., Mofijur, M., Hasan, M.M., Rasul, M.G., Jahirul, M.I., Forruque Ahmed, S., et al. (2023) Alternative Fuels to Reduce Greenhouse Gas Emissions from Marine Transport and Promote UN Sustainable Development Goals. Fuel, 338, Article ID: 127220. https://doi.org/10.1016/j.fuel.2022.127220
[5]
Tanaka, T., Guo, J. and Wang, X. (2023) Price Interconnection of Fuel and Food Markets: Evidence from Biodiesel in the United States. GCBBioenergy, 15, 886-899. https://doi.org/10.1111/gcbb.13055
[6]
Malaysia (2025) Malaysia Targets Third GHG Emissions Reduction (NDC 3.0) 15 to 30 Million Tonnes of CO2 Equivalent by 2035. Ministry of Natural Resources and Environmental Sustainability. https://themalaysianreserve.com/2026/01/20/malaysia-submits-ndc-3-0-as-nres-outlines-path-to-net-zero/
[7]
(2023) European Commission on 2050 Target, EC. https://commission.europa.eu/energy-climate-change-environment_en
IRENA (2023) Statistics Data. https://www.irena.org/Data
[13]
Hassan Pranta, M. and Muk Cho, H. (2025) A Comprehensive Review of the Evolution of Biodiesel Production Technologies. EnergyConversionandManagement, 328, Article ID: 119623. https://doi.org/10.1016/j.enconman.2025.119623
[14]
Naseef, H.H. and Tulaimat, R.H. (2025) Transesterification and Esterification for Biodiesel Production: A Comprehensive Review of Catalysts and Palm Oil Feedstocks. EnergyConversionandManagement: X, 26, Article ID: 100931. https://doi.org/10.1016/j.ecmx.2025.100931
[15]
Goh, M. and Yang, K. (2026) Malaysia Weighs Targeted Fuel Subsidy Cuts for Higher-Income Groups as Costs Surge. https://www.channelnewsasia.com/asia/malaysia-fuel-subsidy-higher-income-rising-energy-prices-oil-biodiesel-middle-east-6103596
[16]
Energy Policy Research Foundation (EPRINC) (2023) Estimating U.S. Biodiesel Cost. https://eprinc.org/wp-content/uploads/2023/07/EPRINC-Chart2023-22-USBiodieselCosts-Version2.pdf
[17]
Silviana, S., Anggoro, D.D., Hadiyanto, H., Salsabila, C.A., Aprilio, K., Utami, A.W., etal. (2022) A Review on the Recent Breakthrough Methods and Influential Parameters in the Biodiesel Synthesis and Purification. InternationalJournalofRenewableEnergyDevelopment, 11, 1012-1036. https://doi.org/10.14710/ijred.2022.43147
[18]
Knothe, G., Gerpen, J.V. and Krahl, J. (2005) The Biodiesel Handbook. AOCS Press.
[19]
Oluji？, ？., J？decke, M., Shilkin, A., Schuch, G. and Kaibel, B. (2009) Equipment Improvement Trends in Distillation. ChemicalEngineeringandProcessing: ProcessIntensification, 48, 1089-1104. https://doi.org/10.1016/j.cep.2009.03.004
[20]
Martín, M. and Grossmann, I.E. (2012) Simultaneous Optimization and Heat Integration for Biodiesel Production from Cooking Oil and Algae. Industrial&EngineeringChemistryResearch, 51, 7998-8014. https://doi.org/10.1021/ie2024596
[21]
Ignat, R.M. and Kiss, A.A. (2012) Energy Efficient Recovery of Methanol and Glycerol in Biodiesel Production. Chemical Engineering Transactions, 29, 1141-1146.
[22]
Foo, D. (2017) Chemical Engineering Process Simulation. Elsevier.
[23]
Westerbeg, A.W., Hutchison, H.P. and Motard, R.L. (1979) Process Flowsheeting. Cambridge University Press.
[24]
Motard, R.L., Shacham, M. and Rosen, E.M. (1975) Steady State Chemical Process Simulation. AIChEJournal, 21, 417-436. https://doi.org/10.1002/aic.690210302
[25]
Haydary, J. (2018) Chemical Process Design and Simulation: Aspen Plus and Aspen Hysys Applications. Wiley. https://doi.org/10.1002/9781119311478
[26]
Ji？í, K., Friedler, F., Bulatov, I. and Varbanov, P. (2011) Sustainability in the Process Industry: Integration and Optimization. McGraw-Hill.
[27]
Gandikota, M.S. and Davis, J.F. (1990) An Expert System Framework for the Preliminary Design of Process Flowsheets. In: Ramani, S., Chandrasekar, R. and Anjaneyulu, K.S.R., Eds., Knowledge Based Computer Systems, Springer-Verlag, 88-104. https://doi.org/10.1007/bfb0018371
[28]
Frangopoulos, C.A., Von Spakovsky, M.R. and Sciubba, E. (2002) A Brief Review of Methods for the Design and Synthesis Optimization of Energy Systems. International Journal of Thermodynamics, 5, 151-160.
[29]
Aspen Tech (2000) Aspen Plus—User Guide V 10.2. Aspen Technology Inc.
[30]
Hill, D., Fred, C. and Justice, P.E. (2011) Understand Thermodynamics to Improve Process Simulation. American Institute of Chemical Engineers (AIChE). http:///www.aiche.org/cep
[31]
Zhang, Y., Dube, M.A., McLean, D.D. and Kates, M. (2003) Biodiesel Production from Waste Cooking Oil: 1. Process Design and Technological Assessment. BioresourceTechnology, 89, 1-16. https://doi.org/10.1016/s0960-8524(03)00040-3
[32]
García-García, J.A., Enríquez, J.G., Ruiz, M., Arévalo, C. and Jiménez-Ramírez, A. (2020) Software Process Simulation Modeling: Systematic Literature Review. ComputerStandards&Interfaces, 70, Article ID: 103425. https://doi.org/10.1016/j.csi.2020.103425
[33]
Patle, D.S., Sharma, S., Ahmad, Z. and Rangaiah, G.P. (2014) Multi-Objective Optimization of Two Alkali Catalyzed Processes for Biodiesel from Waste Cooking Oil. EnergyConversionandManagement, 85, 361-372. https://doi.org/10.1016/j.enconman.2014.05.034
[34]
Kiss, A.A. (2009) Novel Process for Biodiesel by Reactive Absorption. SeparationandPurificationTechnology, 69, 280-287. https://doi.org/10.1016/j.seppur.2009.08.004
[35]
West, A., Posarac, D. and Ellis, N. (2008) Assessment of Four Biodiesel Production Processes Using HYSYS.Plant. BioresourceTechnology, 99, 6587-6601. https://doi.org/10.1016/j.biortech.2007.11.046
[36]
Di Nicola, G., Moglie, M., Pacetti, M. and Santori, G. (2010) Bioenergy II: Modeling and Multi-Objective Optimization of Different Biodiesel Production Processes. InternationalJournalofChemicalReactorEngineering, 8, Article A16. https://doi.org/10.2202/1542-6580.1951
[37]
Sharma, S. and Rangaiah, G.P. (2013) Multi-Objective Optimization of a Bio-Diesel Production Process. Fuel, 103, 269-277. https://doi.org/10.1016/j.fuel.2012.05.035
[38]
Aboelazayem, O., Gadalla, M. and Saha, B. (2018) Design and Simulation of an Integrated Process for Biodiesel Production from Waste Cooking Oil Using Supercritical Methanolysis. Energy, 161, 299-307. https://doi.org/10.1016/j.energy.2018.07.139
[39]
Granjo, J.F.O., Duarte, B.P.M. and Oliveira, N.M.C. (2017) Integrated Production of Biodiesel in a Soybean Biorefinery: Modeling, Simulation and Economical Assessment. Energy, 129, 273-291. https://doi.org/10.1016/j.energy.2017.03.167
[40]
Medeiros, H.A.D., Chiavone-Filho, O. and Rios, R.B. (2020) Influence of Estimated Physical Constants and Vapor Pressure for Esters in the Methanol/Ethanol Recovery Column for Biodiesel Production. Fuel, 276, Article ID: 118040. https://doi.org/10.1016/j.fuel.2020.118040
[41]
Petrescu, L., Galusnyak, S.C., Chisalita, D.A. and Cormos, C.C. (2020) Modelling and Simulation of Methanol and Biodiesel Production Processes Using Innovative Technologies. Chemical Engineering Transactions, 80, 181-186.
[42]
B. Rios, R., Evangelista Neto, A.A., D. Medeiros, H.A., M. Silva, F.F., M. Oliveira, H.N., L. Barros Neto, E., etal. (2023) Liquid-Liquid Equilibria of Glycerol + Alcohol + Safflower Biodiesel Systems: Measurement and Modeling. JournalofChemical&EngineeringData, 68, 1716-1727. https://doi.org/10.1021/acs.jced.3c00185
[43]
Azad, A.K., Jadeja, A.C., Doppalapudi, A.T., Hassan, N.M.S., Nabi, M.N. and Rauniyar, R. (2024) Design and Simulation of the Biodiesel Process Plant for Sustainable Fuel Production. Sustainability, 16, Article 3291. https://doi.org/10.3390/su16083291
[44]
Kuah, C.T., Koh, Q.Y., Rajoo, S. and Wong, K.Y. (2022) Waste Heat Recovery Research—A Systematic Bibliometric Analysis (1991 to 2020). EnvironmentalScienceandPollutionResearch, 30, 72074-72100. https://doi.org/10.1007/s11356-022-21377-6
[45]
Trisha, V., Koh, K.S., Ng, L.Y. and Chok, V.S. (2021) Heat Exchanger Network Retrofit of an Oleochemical Plant through a Cost and Energy Efficiency Approach. ChemEngineering, 5, Article 17. https://doi.org/10.3390/chemengineering5020017
[46]
Zarli, A. (2020) Chapter 6, Oleochemical: All Time Players of Green Chemistry. StudiesinSurfaceScienceandCatalysis, 179, 77-95.
[47]
Koh, K.S., Chew, S.J., Choo, C.M. and Chok, V.S. (2019) Heat Integration of a Boiler and Its Corresponding Environmental Study in an Oleochemical Production Plant: An Industry Case Study in Malaysia. ChemEngineering, 3, Article 82. https://doi.org/10.3390/chemengineering3040082
[48]
Lee, R.A., Koh, K.S., Ng, L.Y. and Chok, C. (2022) Steam Network Optimization and CO2 Reduction in an Oleochemical Production Complex. Authorea. https://doi.org/10.22541/au.165388864.44751941/v1
[49]
Mechaussie, E.M. (2018) Methodology for Efficient Use of Thermal Energy in the Chemical and Petrochemical Industry. Ph.D. Thesis, Ecole Polytechnique Federale De Lausanne.
[50]
(2009) EN 16001, Sustainable Energy Ireland. https://www.seai.ie/search/?magic_roxen_automatic_charset_variable=%C3%A5%C3%A4%C3%B6%E8%8A%9F%40UTF-8&query=EN+16001
[51]
Hotwell, M.T. (2014) Effective Implementation of an ISO 50001 Energy Management System (EnMS). American Society for Quality Press.
[52]
Khong, L.Y. and Chai, P.V. (2025) Energy Management and Waste Heat Recovery in the Malaysian Oleochemical Industry. OpenJournalofEnergyEfficiency, 14, 21-41. https://doi.org/10.4236/ojee.2025.141002
[53]
Craig, B., Smith, C.B., Capehart, B.L. and Rohrer, W.M. (2016) Industrial Energy Efficiency and Energy Management. In: Goswami, D.Y. and Kreith, F., Eds., EnergyManagementandConservationHandbook, CRC Press, 729-735.
[54]
Thollander, P., Karlsson, M., Rohdin, P., Wollin, J. and Rosenqvist, J. (2020) Intro-duction to Industrial Energy Efficiency: Energy Auditing, Energy Management, and Policy Issues. Elsevier. https://doi.org/10.1016/C2018-0-01452-8
[55]
Elkihel, A., Abouelanouar, B. and Gziri, H. (2021) Industrial Energy Audit Methodology for Improving Energy Efficiency—A Case Study. In: Hajji, B., Mellit, A., Marco Tina, G., Rabhi, A., Launay, J. and Naimi, S., Eds., Proceedings of the 2nd International Conference on Electronic Engineering and Renewable Energy Systems, Springer, 675-681. https://doi.org/10.1007/978-981-15-6259-4_70
[56]
Luo, Y. (2016) A Framework for Waste Heat Energy Recovery within Manufacturing. Ph.D. Thesis, University of Loughborough.
[57]
Menghi, R., Papetti, A., Germani, M. and Marconi, M. (2019) Energy Efficiency of Manufacturing Systems: A Review of Energy Assessment Methods and Tools. Journal of Cleaner Production, 240, Article ID: 118276. https://doi.org/10.1016/j.jclepro.2019.118276
[58]
Svensson, A. and Paramonova, S. (2017) An Analytical Model for Identifying and Addressing Energy Efficiency Improvement Opportunities in Industrial Production Systems—Model Development and Testing Experiences from Sweden. JournalofCleanerProduction, 142, 2407-2422. https://doi.org/10.1016/j.jclepro.2016.11.034
[59]
Zhao, H. (2023) Intelligent Management of Industrial Building Energy Saving Based on Artificial Intelligence. Sustainable Energy Technologies and Assessments, 56, Article ID: 103087. https://doi.org/10.1016/j.seta.2023.103087
