http://ir.mu.ac.ke:8080/jspui/handle/123456789/42 2026-04-20T09:29:01Z 2026-04-20T09:29:01Z Maringa, Frankson http://ir.mu.ac.ke:8080/jspui/handle/123456789/10041 2026-01-22T09:09:26Z 2025-01-01T00:00:00Z

Title: Techno-economic assessment of grid-solar-diesel generator battery hybrid energy systems for Kenya Pipeline Company, Eldoret terminal Authors: Maringa, Frankson Abstract: The Kenya Pipeline Company (KPC) Eldoret Terminal uses grid electricity and reliance on backup diesel generator during power outages. This hampers operational efficiency while contributing to financial strain and environmental emissions. With abundance of solar irradiance, there is a need to transition to a sustainable hybrid energy system (HES). The main objective of this study was to carry out a techno- economic assessment of grid-solar PV-diesel generator-battery hybrid energy systems. The specific objectives were to investigate and analyze energy consumption patterns, to design and simulate an optimum grid-solar PV-battery-diesel generator HES using PVsyst and (Hybrid Optimization Model for Multiple Energy Resources) HOMER modelling tools and to perform techno-economic analysis of the optimum hybrid energy system. The methodology outlined a step-by-step approach used to design a HES. The site was selected, and data was collected through surveys with the maintenance team, reviews of structural and utility documents, interviews to gather operational data, and observational entries from a data logger to document the energy profile. The design phase involved configuring a HES that integrated photovoltaic modules with existing diesel generators and grid power, optimized through precise calculations of energy consumption, PV module placement, battery system sizing, and inverter sizing. Simulation tools were utilized to aid in designing and performing economic assessments, determining the system’s feasibility and economic viability through calculations of the Net Present Cost (NPC), Levelized Cost of Energy (LCOE), and emissions. Based on data collected, KPC consumed 108,732 kWh of grid power and diesel generator at the terminal rated at 550 kVA consumed 1,807.31 litres with an energy production of 10,975kW in 2023. The terminal spent about Kshs 17.876 million on provision of electricity in 2023. The hybrid system was introduced a solar PV system covering a total estimated area of 2365 m2 and an initial investment of Kshs 232,938,000, with a payback period of 8 years. The optimized HES entailed the PV module and grid integration, featuring a (LCOE) of 9.83 Kshs/kWh and NPC of Kshs 236 million while producing an annual CO 2 emission of 100,106kg. This scaled down by more than 50%. The study concluded that the grid-solar hybrid connection was well suited for a sustainable energy management system. It was recommended that solar charged batteries be prioritized as the power back up instead of the expensive diesel generator and environmentally polluting.

2025-01-01T00:00:00Z Balogun, Augustine Olamilekan http://ir.mu.ac.ke:8080/jspui/handle/123456789/10027 2026-01-16T07:26:52Z 2025-01-01T00:00:00Z

Title: Development and characterization of pig hair reinforced polypropylene composites for potential Automobile applications Authors: Balogun, Augustine Olamilekan Abstract: The automotive industry's pursuit of lightweight, sustainable materials, coupled with the environmental challenge of managing agricultural waste, necessitates innovative material solutions. This research addresses this dual challenge by investigating the viability of using pig hair—an abundant and underutilized by-product of the pork industry—as a reinforcement in a polypropylene (PP) matrix. The study aimed to develop and optimize a novel biocomposite and characterize its mechanical and physical properties for potential automotive applications. Using a compression molding technique, pig hair fibers were pre-treated with a 5% NaOH solution and incorporated into a PP matrix. A Central Composite Design (CCD) under Response Surface Methodology (RSM) was employed to systematically optimize three key process parameters: Fiber length (7-15 mm), Fiber weight fraction (2-6 wt%), and molding temperature (170-190°C). The resulting composites were characterized for their tensile, flexural, and impact strength, as well as their morphology and thermal conductivity. The statistical analysis revealed that all three parameters significantly influenced the composite's mechanical properties. The optimized process conditions were identified as a Fiber length of 11.25 mm, a Fiber weight fraction of 4.5%, and a molding temperature of 183.4°C, which yielded a maximum predicted tensile strength of 24.16 MPa. The composite also demonstrated improved thermal insulation compared to virgin PP. The key conclusion of this study is that pig hair can be effectively utilized as a reinforcing fiber to produce a viable, lightweight composite with predictable mechanical properties suitable for non-structural automotive components like interior trim and door panels. It is recommended that future research explore the use of coupling agents to further enhance fiber-matrix adhesion. For policy and practice, it is recommended that abattoirs and agricultural bodies explore the implementation of collection and pre-processing systems to create a new value chain for pig hair, transforming this waste product into a valuable industrial feedstock

2025-01-01T00:00:00Z Mwalimu, Rashid Nzaphila http://ir.mu.ac.ke:8080/jspui/handle/123456789/9973 2025-10-15T07:35:48Z 2025-01-01T00:00:00Z

Title: Occurrence, risk assessment and elimination of chemicals of emerging concerns in wastewater treatment plants In Western, Kenya Authors: Mwalimu, Rashid Nzaphila Abstract: Chemicals of emerging concern (CECs) are a global threat due to their adverse effects on aquatic organisms and human health. Wastewater treatment plants (WWTPs) are a significant source of these compounds into the environment at varying concentrations ranging from ng/L to µg/L. However, data on the removal efficiencies of waste treatment technologies in Africa are limited. Therefore, this study aimed to assess the occurrence, removal efficiency, and potential toxic risk posed by CECs in wastewater treatment plants. The objectives were to: i) identify and quantify CECs from WWTPs, ii) evaluate the removal efficiencies of CECs by the selected WWTPs, and iii) perform ecotoxicological risk assessment of the detected CECs in the effluent of the four selected WWTPs in western Kenya. Solid-phase extraction and high-performance liquid chromatography coupled with high-resolution mass spectrometry were used for sample preparation and analysis, respectively. A target list of 795 compounds, including pesticides and biocides, pharmaceuticals, and industrial compounds, among others, was used. The toxic unit (TU) approach was applied to evaluate the risk posed by the contaminants present in the effluent of the WWPs. A total of 353 compounds were detected across influents and effluents of the sampled WWPs, with the most frequently detected compound classes being pharmaceuticals (102), pesticides (70), and industrial chemicals (72). The highest influent concentrations were detected for caffeine (830 µg/L), deoxycholic acid (719 µg/L), 2-oxindole (43 µg/L), ibuprofen (24 µg/L), and dichlorvos (14 µg/L). Notably, previously undocumented antiviral drugs such as emtricitabine and amantadine were reported for the first time at concentrations ranging from 4 ng/L to 536 ng/L. In the effluent, high concentrations were detected for caffeine (17 µg/L), TMDD (1.3 µg/L), cetirizine (2.3 µg/L), dichlorvos (1.3 µg/L), and sucralose (3.1 µg/L). Removal efficiencies of the compounds varied greatly, with 286 compounds having positive removals and 67 compounds with negative removal efficiencies. Compounds with > 80% removal efficiency included ibuprofen, trimethoprim, TMDD, diclofenac, and diazinon. WWTPs employing a combination of primary and secondary stabilization ponds, activated sludge, and trickling filters performed better in removing CECs. Risk assessment revealed crustaceans had the highest potential risk, with toxic units (TUs) up to 5.5, driven primarily by dichlorvos and diazinon. Algae and fish predominantly experienced chronic toxicity, with dichlorvos being the primary driver of toxicity for algae and didecyldimethylammonium for fish. This study underscores the substantial contribution of WWTPs to contamination of aquatic environments, with pesticides, pharmaceuticals, and industrial chemicals being the most persistent. It provides evidence-based data on the need for technological advancements in CEC removal, chemical use, and disposal, as well as robust monitoring and regulatory measures.

2025-01-01T00:00:00Z Koech, Vincent Kipkemboi http://ir.mu.ac.ke:8080/jspui/handle/123456789/9972 2025-10-15T07:17:22Z 2025-01-01T00:00:00Z

Title: Performance evaluation of a Retrofitted Cook Stove by co firing Biomass with steam, spirit and Bio-diesel Authors: Koech, Vincent Kipkemboi Abstract: The continued use of biomass cookstoves in households and the traditional open fires for cooking is not only a major health hazard but also an environmental hazard. Although biomass offers a sustainable and carbon neutral source of energy, its inefficient use in household cooking has led to the indoor air pollution due to smoke emission resulting to respiratory and other health problems. The main objective of this study was to determine the performance of a retrofitted cook stove co-firing biomass with steam, spirit and bio-diesel. The specific objectives were to design and fabricate a retrofitted cookstove, determine the thermal efficiency of biomass when steam, biodiesel and spirit are used as gasification agent and to carry out the techno-economic analysis of the retrofitted cookstove. Mild steel, copper and aluminium were selected as the construction material. The computer aided drawing (CAD) was used to design the cook stove based on cook stove energy requirements, reactor diameter, height of the reactor and the heat exchange area for the gasification agent (steam). The fabrication was guided by technical 2D and 3D CAD drawings. The empirical relations for the design were borrowed from closely related literature, such as energy requirements, fuel consumption rate, reactor diameter, height of the reactor and heat exchanger for steam. The performance was based on already established standard methods which includes efficiency, fire power and burning rate. The analysis revealed an efficiency of retrofitted stove when biodiesel, spirit and water were used was 53.83%, 37.65% and 14.75% respectively. The fire power for retrofitted stove for water, spirit and biodiesel were 76.66 J/s, 80.93J/s and 83.93J/s respectively. The burning rate for retrofitted stove for water, spirit and biodiesel were 0.25g/sec, 0.27g/sec and 0.28g/sec respectively. The boiling cost in KES for 1 liter of water in Retrofitted stove, Envirofit, Jiko Koa, Clay stove, and Kenya ceramic jiko were 2.0,20.0,23.9,31.1 and 31.6 respectively. The initial cost in KES for acquiring Retrofitted stove, Envirofit, Jiko koa, Kenya ceramic jiko and Clay stove were 4,895, 5,470, 5,499, 500 and 2,500 respectively. The Power for Envirofit, Jiko koa, Kenya ceramic jiko, Clay stove and Traditional stove were 0.95J/s,0.71J/s,0.37J/s,0.36J/s and 0.35J/s respectively. In conclusion retrofitted cook stove was more efficient and emits limited smoke when cooking hence friendly to the environment and improve rate of cooking. Further studies be done on rate and amount of gas produced as syngas from retrofitted cook stove

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