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All Journal R.E.M (Rekyasa Energi Manufaktur) Jurnal Jurnal Pengabdian KOLABORATIF IJIMCE : International Journal of Innovation in Mechanical Construction and Energy
YAWAS, Danjuma
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Automotive Engineering Civil Engineering, Building, Construction & Architecture Electrical & Electronics Engineering Energy Engineering Environmental Science Industrial & Manufacturing Engineering Materials Science & Nanotechnology Social Sciences

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Development of a Waste Plastic-to-Fuel Conversion System for Sustainable Energy Generation in Urban Nigeria Unegbu, Hyginus; YAWAS, Danjuma
R.E.M. (Rekayasa Energi Manufaktur) Jurnal Vol 10 No 2 (2025): December
Publisher : Universitas Muhammadiyah Sidoarjo

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.21070/r.e.m.v10i2.1775

Abstract

Plastic waste pollution has emerged as a critical environmental and public health concern in Nigeria’s rapidly urbanising regions, where improper disposal and inefficient waste management systems persist. In parallel, the country faces acute energy insecurity, largely driven by erratic diesel supply and rising fossil fuel costs. This study presents the design, optimisation, and techno-environmental evaluation of a decentralised pyrolysis-based conversion system for transforming plastic waste into liquid fuel. Polypropylene (PP), high-density polyethylene (HDPE), low-density polyethylene (LDPE), and polystyrene (PS) were thermally degraded at controlled temperatures between 350°C and 500°C under inert conditions. Experimental trials revealed that oil yield increased with temperature, peaking at 450°C for all polymers. PP demonstrated the highest yield (65.1%) followed by PS (63.0%), HDPE (62.5%), and LDPE (60.4%). Fuel characterisation showed calorific values of up to 42.7 MJ/kg and physicochemical properties within acceptable diesel standards. Emissions analysis using flue gas monitoring confirmed low outputs of CO, NOx, and SO₂, all within Euro VI regulatory limits. Energy efficiency was highest for PP-derived fuel at 71.4%. Techno-economic modelling, based on a 10-year operational horizon, produced a net present value of ₦11.8 million, an internal rate of return of 28.4%, and a break-even fuel price of ₦290/litre. Statistical modelling further validated temperature and polymer type as primary determinants of yield performance. The findings demonstrate that decentralised plastic pyrolysis systems can simultaneously address urban waste accumulation, reduce environmental emissions, and provide affordable alternative fuels, making them suitable for integration into Nigeria’s circular economy and energy access strategies.
Toward a Regional Energy Future: Opportunities and Challenges for Cross-Border Renewable Power Integration in West Africa Unegbu, Hyginus Chidiebere Onyekachi; YAWAS, Danjuma
Jurnal Pengabdian KOLABORATIF Vol. 4 No. 1 (2026): January
Publisher : Faculty of Engineering, Universitas Semarang

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.26623/kolaboratif.v4i1.12796

Abstract

Achieving reliable, affordable, and sustainable electricity access remains a critical challenge for power systems in West Africa. Although the region possesses abundant renewable energy resources, fragmented national planning and limited cross-border transmission interconnections continue to restrict optimal resource utilization. This study investigates the technical, economic, and institutional implications of cross-border renewable power integration within the ECOWAS regional power system. Power system modeling was conducted using the PyPSA platform, representing a 14-bus regional network simulated over a full annual operating cycle with high-resolution demand and generation profiles. Three operational scenarios were assessed: Business-as-Usual, private-led Power Purchase Agreements (PPAs), and Coordinated Regional Integration. System performance was evaluated using system marginal costs, renewable energy penetration, transmission utilization, and reliability indices. The results indicate that the Coordinated Integration scenario significantly outperforms the other scenarios, achieving up to a 36% reduction in average system marginal costs, renewable energy penetration exceeding 60%, and improved grid reliability through enhanced load balancing and reserve-sharing mechanisms. In contrast, the Business-as-Usual and PPA-based scenarios exhibit lower performance due to inefficient transmission utilization and institutional fragmentation. The findings highlight that infrastructure expansion alone is insufficient to ensure optimal regional power system performance. Effective integration requires harmonized operational standards, consistent regulatory frameworks, and strengthened regional institutions. Enhancing the roles of the West African Power Pool (WAPP) and the ECOWAS Centre for Renewable Energy and Energy Efficiency (ECREEE), supported by performance-based regional investment mechanisms, is essential to unlock the full benefits of cross-border energy cooperation. This study provides a technically grounded and policy-relevant framework to accelerate energy transition, improve power system resilience, and foster economic integration across West Africa.
Conversion of Waste Tyres into High-Energy Fuel Products Using Pyrolysis Technology Unegbu, Hyginus; YAWAS, Danjuma
IJIMCE : International Journal of Innovation in Mechanical Construction and Energy Vol. 2 No. 3 (2025): IJIMCE : International Journal of Innovation in Mechanical Construction and Ene
Publisher : Universitas Negeri Padang

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.24036/ijimce.v2i3.71

Abstract

The accumulation of waste tyres poses a critical environmental and public health concern due to their non-biodegradability, complex composition, and fire hazard potential. This study explores the thermochemical valorization of end-of-life tyres into high-energy fuel products through pyrolysis, emphasizing process optimization, product quality assessment, and environmental performance. A fixed-bed pyrolysis system was operated across a temperature range of 350°C to 550°C to evaluate its influence on product distribution and yield characteristics. The maximum oil yield of 52.3% was obtained at 500°C, representing the optimal balance between primary depolymerization and suppression of secondary cracking reactions. The pyrolysis oil exhibited a high heating value (43.6 MJ/kg), suitable for energy applications, but exceeded international standards for sulfur content and viscosity, necessitating upgrading prior to use in transportation fuels. The gaseous fraction, enriched with hydrogen and light hydrocarbons, showed strong potential for process self-sufficiency and co-generation. Solid char demonstrated favorable physicochemical properties for application as a fuel or adsorbent material. Statistical modeling using linear regression accurately predicted oil yield trends, and Aspen Plus® simulations closely aligned with experimental results, validating the process model for scale-up. A comparative life cycle assessment revealed that pyrolysis significantly outperforms incineration in terms of greenhouse gas reduction, energy recovery, and particulate matter emissions. These findings confirm that tyre pyrolysis is a technically feasible and environmentally advantageous approach for sustainable waste management and fuel generation. Further integration with refining technologies and renewable energy inputs is recommended to enhance commercial viability.
Physics-Informed Neural Networks for Predictive Maintenance in Nigerian Hydropower Infrastructure Unegbu, Hyginus; YAWAS, Danjuma
IJIMCE : International Journal of Innovation in Mechanical Construction and Energy Vol. 2 No. 3 (2025): IJIMCE : International Journal of Innovation in Mechanical Construction and Ene
Publisher : Universitas Negeri Padang

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.24036/ijimce.v2i3.72

Abstract

Ensuring the operational integrity of hydropower infrastructure is critical for maintaining energy security and grid stability in Nigeria. However, conventional predictive maintenance frameworks are hindered by inconsistent data availability, poor sensor coverage, and a lack of physical interpretability. This study presents a robust Physics-Informed Neural Network (PINN) architecture tailored for predictive maintenance in Nigerian hydropower systems. By embedding domain-specific physical laws—namely Bernoulli’s principle, the turbine power equation, and Fourier’s law of heat conduction—directly into the model’s loss function, the proposed PINN integrates physical reasoning with deep learning to produce accurate and explainable degradation forecasts. Simulated operational data reflective of real-world hydropower conditions were used to train and evaluate the model. Comparative analysis against Long Short-Term Memory (LSTM) networks and Random Forest (RF) regressors demonstrated the superior performance of the PINN, which achieved an RMSE of 4.75 days and an R² value of 0.88. Furthermore, physics residuals across all governing constraints were consistently below 0.04, indicating strong physical consistency. The model accurately predicted failure in three fault scenarios—runner blade erosion, stator insulation decay, and penstock pressure surges—with lead times ranging from 7.5 to 11 days, thereby enabling actionable intervention before catastrophic breakdown. A real-time monitoring interface was developed to visualize model outputs, risk thresholds, and residual dynamics, facilitating operator trust and integration into existing maintenance workflows. This research establishes the PINN as a scalable and domain-aware solution, well-suited for advancing predictive maintenance capabilities in Nigeria’s evolving hydropower infrastructure.
Co-Authors Unegbu, Hyginus Unegbu, Hyginus Chidiebere Onyekachi