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Modelling Energy Consumption with Value Stream Mapping and Dual Energy Stream Approach: Case Study of Tea Processing facility
Subject area: Science,Engineering and Technology · Area of research: Energy Efficiency
DOI: https://doi.org/10.64388/IREV9I11-1718360
Abstract
The tea processing industry is fundamentally energy intensive, relying heavily on both thermal and electrical energy across manufacturing chain. Majority of tea manufacturing factories in Kenya under K.T.D.A management operate with sub-optimal energy management system, therefore missing opportunities for energy saving. Regular energy audits are insufficient in addressing high energy consumption. This research addressed high energy consumption in Kenyan tea manufacturing facilities using energy value stream map (EVSM) approach and by focusing on electrical energy. The main objective of the research was to model energy utilization using EVSM and dual energy stream approach for the purpose of optimizing section energy consumption. Using Kapkoros Tea Factory as a case study, the research systematically mapped energy consumed in production in order to visualize energy flows, section inefficiencies and bottlenecks. Electrical energy consumption was determined using data logger and energy smart meters. Efficiencies were determined using tachometers and rated motor torques. Modelling and simulation were then performed using Matlab for system optimization. The results were validated against EPRA, SLSEA and BEE benchmarks. The research determined that EVSM is viable tool for energy mapping in tea manufacturing facility. The case study facility had an energy use intensity (EUI) of 0.535Kwh/KgMT with an OEE of 85% and EER of 1.2. But through modelling and simulation the factory could operate at EUI of 0.437Kwh/KgMT with an OEE of 93% and EER of 0.92. This could be achieved through replacement of cast iron axial fans with alluminium VFDs. Installing continuous withering technology in withering section and updating maintenance procedures. The results obtained compared well with BEE benchmark of 0.47Kwh/KgMT and SLSEA standard of 0.51Kwh/KgMT. Under optimal consumption, energy efficiency ratio (EER) of the factory was determined to be 0.86 against SLSEA and 0.92 against BEE. The outcome of this research could become a base setter on how factories in Kenya should manage energy consumption in their utilities with potential scalability across the tea industry. The research highlighted key interventions through proposed energy saving strategies and demonstrated EVSM potential for energy efficiency management framework.
Keywords
Energy, Modelling, EVSM, EUI, EER
References
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How to cite this paper
@article{1718360,
author = {Leonard Ngetich, Charles Ondieki, Julius Ogola},
title = {Modelling Energy Consumption with Value Stream Mapping and Dual Energy Stream Approach: Case Study of Tea Processing facility},
journal = {Iconic Research And Engineering Journals},
year = {2026},
volume = {9},
number = {11},
pages = {5629-5643},
issn = {2456-8880},
url = {https://www.irejournals.com/formatedpaper/1718360.pdf},
abstract = {The tea processing industry is fundamentally energy intensive, relying heavily on both thermal and electrical energy across manufacturing chain. Majority of tea manufacturing factories in Kenya under K.T.D.A management operate with sub-optimal energy management system, therefore missing opportunities for energy saving. Regular energy audits are insufficient in addressing high energy consumption. This research addressed high energy consumption in Kenyan tea manufacturing facilities using energy value stream map (EVSM) approach and by focusing on electrical energy. The main objective of the research was to model energy utilization using EVSM and dual energy stream approach for the purpose of optimizing section energy consumption. Using Kapkoros Tea Factory as a case study, the research systematically mapped energy consumed in production in order to visualize energy flows, section inefficiencies and bottlenecks. Electrical energy consumption was determined using data logger and energy smart meters. Efficiencies were determined using tachometers and rated motor torques. Modelling and simulation were then performed using Matlab for system optimization. The results were validated against EPRA, SLSEA and BEE benchmarks. The research determined that EVSM is viable tool for energy mapping in tea manufacturing facility. The case study facility had an energy use intensity (EUI) of 0.535Kwh/KgMT with an OEE of 85% and EER of 1.2. But through modelling and simulation the factory could operate at EUI of 0.437Kwh/KgMT with an OEE of 93% and EER of 0.92. This could be achieved through replacement of cast iron axial fans with alluminium VFDs. Installing continuous withering technology in withering section and updating maintenance procedures. The results obtained compared well with BEE benchmark of 0.47Kwh/KgMT and SLSEA standard of 0.51Kwh/KgMT. Under optimal consumption, energy efficiency ratio (EER) of the factory was determined to be 0.86 against SLSEA and 0.92 against BEE. The outcome of this research could become a base setter on how factories in Kenya should manage energy consumption in their utilities with potential scalability across the tea industry. The research highlighted key interventions through proposed energy saving strategies and demonstrated EVSM potential for energy efficiency management framework.},
keywords = {Energy, Modelling, EVSM, EUI, EER},
month = {May},
doi = {https://doi.org/10.64388/IREV9I11-1718360}
}