International Journal of Renewable Energy and Environment
The International Journal of Renewable Energy and Environment (IJREE) is a publication of the National Centre for Energy and Environment. The Journal contains scientific research into all aspects of Renewable Energy resources, their interaction with the environment and relationship with man. This journal is multidisciplinary in approach and interdisciplinary in scope promoting findings in a wide range of subject areas: Renewable Energy Technology, Agricultural Engineering Technology, Biomass Feedstock and Conversion, Environmental Forensics, Environmental Law and Policy, Environmental Management, Human Health and Life cycle Assessment, Biological Modelling, Environmental Engineering, Energy Efficiency, Climate Change and Carbon Capture Technology. In view of the multidisciplinary nature of the journal, the Editorial Board and Editorial Advisory Committee are made up of a broad spectrum of internationally recognized scientist, academicians and policy makers who will encourage publications that display only the highest standards of international scholarship.
National Centre for Energy and Environment
Accepted paper becomes the permanent property of the International Journal of Renewable Energy and Environment (IJREE) and may not be reproduced by any means without the written permission of the Editorial board.
THE POTENTIALS, PROBLEMS AND PROSPECTS OF BIOMASS ENERGY: A REVIEW
Global increase in energy demand and dependence on fossil fuels have highlighted the need for sustainable alternatives, prompting expanded research into biomass as a renewable energy resource. Biomass are materials that have their route from organic materials like plants and animals, including by-products of agricultural, food and livestock industries have been confirmed as a source of renewable energy. This review provides an extensive assessment of energy derivative from biomass, their properties, prospect and challenges in utilisation as a source of energy. Papers from different authors were reviewed and their results point towards the problems encountered in their utilization; the merits proclaimed by authors of previous research have been pointed. Despite the hype in sustainability, reliability and environmental conserving properties, most countries are still over-reliant on fossil fuel. Therefore, this review highlights the merits and demerits of the use of biomass energy as a close substitute for conventional forms of energy It is concluded that most of the harmonisation techniques of using biomass a source of energy is still at the laboratory scale in some developing countries and ways of commercialising this technology was suggested.
Copyright (c) 2026 International Journal of Renewable Energy and Environment https://creativecommons.org/licenses/by-nc/4.0
ASSESSMENT OF SPATIAL DISTRIBUTION OF HEAVY METALS IN ROADSIDE SOILS AND SOME VEGETALES ALONG NNAMDI AZIKIWE EXPRESS WAY, KADUNA.
The research aimed to assess the spatial distribution of heavy metals in some vegetables and roadside soils along the Nnamdi Azikiwe Expressway in Kaduna. The soil samples were collected at random from nine locations down to a depth of 20 cm in replicates. In the same area where the soil samples were collected, the vegetable samples were likewise chosen at random. The Nariya farm provided the control samples. The samples were allowed to air dry, mixed, and sieved. Nine soils and twenty-seven vegetables were used to prepare the samples. The samples were then digested using the wet technique. Using a pH meter and the conventional Walkley-Black method, the following physiochemical parameters were measured: pH, electrical conductivity, organic carbon, and soil organic matter. Atomic Absorption Spectroscopy was used to assess the concentrations of Pb, Cd, Zn, Cu, and Ni in soil and vegetable samples that were gathered from the roadside at Kawo, Panteka, Kurmin Mashi, Badikko, Tudun Wada, Kabala West, Kudenda, Nassarawa, and Trikania. The findings showed that the soil's pH was generally basic (7.8) and somewhat acidic (6.9). At Kawo and Nassarawa, the EC value was 0.278 ds/cm and the OC value was 12.0g/kg. Zn had the greatest mean concentration in mg/kg of Pb, Cd, Zn, Cu, and Ni, measuring 166.40. The same was true for vegetables, with Zn values of 278.28, 230.90, and 274.90 for spinach, lettuce, and cabbage, respectively. The contamination factor indicates that Ni is marginally enhanced in vegetables at Badikko and Tudun Wada and below the detection limit in all soil samples. For every metal, the translocation factor was less than 1, however at Kawo, Panteka, Badikko, Tudun Wada, and Nassarawa. With the exception of one location that exhibits heavy pollution with PLI >1, the area was not significantly polluted. Nonetheless, the assessment's findings show that there was an increased concentration of Zn and Pb at all nine locations, which was consistent with findings from other researchers. As a result, the toxicants were below the NESREA-established permissible limit. However, because of the metals present from various operations that took place at the site, the concentration of these metals does not follow a regular pattern; instead, fluctuation was seen in the sample. To reduce the spread of harmful contaminants into the environment, government organizations should, however, provide for legislation, awareness, education, waste management, a modern transportation system, and regular analysis.
THERMODYNAMIC AND PERFORMANCE ANALYSIS OF BOX-TYPE SOLAR COOKERS: A REVIEW (2015–2025)
Access to clean cooking energy remains a critical challenge in sub-Saharan Africa despite abundant solar irradiance. This study presents a systematic review and meta-analysis of box-type solar cookers published between 2015 and 2025, integrating first-law and second-law thermodynamic assessment. Nineteen experimental and field-based studies were synthesized using a random-effects model. The pooled thermal efficiency was 34.7% (95% CI: 32.9–36.5%), while reported exergy efficiency ranged between 8–15%, indicating substantial irreversibility primarily due to radiative and convective losses. Standardized mean difference analysis (Hedges’ g = 0.82) confirms that double-reflector configurations produce statistically significant performance improvements compared to single-reflector systems. Insulation improvements contributed moderately but with diminishing marginal gains. A generalized predictive efficiency correlation and uncertainty propagation framework are proposed to enable standardized cross-study benchmarking. Despite thermodynamic advancement, adoption rates remain below 20% in several semi-arid regions, demonstrating that engineering optimization alone does not guarantee large-scale deployment. The study provides an integrated analytical foundation for evaluating thermodynamic ceilings and socio-technical scalability of solar cooking technologies.
BIO-ACCUMULATION OF HEAVY METALS AND ASSESSMENT OF HUMAN HEALTH RISKS ASSOCIATED WITH THE CONSUMPTION OF CALLINECTES AMNICOLA AND PENAEUS MONODON FROM ESCRAVOS ESTUARY, DELTA STATE, NIGERIA
This study examined Ni and Pb concentrations in sediment, Callinectes amnicola, and Penaeus monodon from Escravos Estuary (EE), Delta State, Nigeria. The estuary was divided into three stations (X, Y, Z) based on fish landing sites, while seasonal sampling was dry (January to March) and wet (April to June) seasons in 2025. Sediment, C. amnicola, and P. monodon were collected for six months and analyzed for nickel, lead, and health risk indices—Target Hazard Quotient (THQ), and Hazard Index (HI)—using standard procedures. Data were subjected to descriptive and inferential statistics at 5% significance. Results revealed significant spatial and seasonal concentrations of nickel in sediments, which peaked at station Y (0.06±0.02 mg/kg) and were lowest at X (0.03±0.02 mg/kg). In contrast, seasonal values ranged from 0.03±0.02 to 0.05±0.01 mg/kg. Lead was highest at X (0.04±0.02 mg/kg) and lowest at Y (0.04±0.01 mg/kg), with seasonal values 0.02±0.01–0.03±0.01 mg/kg. In C. amnicola, Ni-THQ was 0.0758, HI 0.6754, while P. monodon showed Ni-THQ 0.0249, HI 0.6710. Rising Ni and Pb levels, alongside elevated risk indices, indicate threats to species abundance and human consumers. Regular monitoring of EE is recommended for sustainable fisheries and public health protection.
A COMPARATIVE REVIEW OF BIOFUELS AND ELECTRIC PROPULSION FOR SMALL-SCALE MARINE TRANSPORTATION IN NIGERIA
Nigeria's small-scale marine transport sector which encompasses inland waterways, coastal ferries, fishing vessels, and naval patrol craft operating across approximately 10,000 kilometres of waterways, remains heavily dependent on petrol and diesel, generating significant air pollution, greenhouse gas emissions, and energy insecurity. This review systematically compares two alternative energy pathways; biofuels (biodiesel, bioethanol, and biogas), and electric propulsion (battery-electric and hybrid-electric), for applicability to Nigerian small-scale marine vessels (5–50 m). Evaluated against technical feasibility, environmental performance, economic viability, and infrastructural readiness, the analysis demonstrates that hybrid setups utilizing battery-electric systems with biofuel-powered engines provide the best results across various metrics, and biodiesel offers the most immediately deployable pathway through drop-in compatibility with existing engines; while battery-electric propulsion is superior for short-route urban ferries contingent on grid improvements. The exploration closes with a phased, portfolio-based transition strategy with clear regulatory and financing recommendations.
MODELING AND OPTIMIZATION OF PROCESS CONDITIONS INFLUENCE ON GLUCOSE, XYLOSE AND BIOETHANOL YIELD FROM LIGNOCELLULOSIC WASTE PALM FRUIT BUNCHES
This study examined the effect of processing parameters (acid concentration, temperature and process duration) on the yield of glucose, xylose and bioethanol synthesized from lignocellulosic waste palm fruit bunches. Raw material was procured from a palm oil processing company in Port-Harcourt, Nigeria. It was mechanically communited, characterized and hydrolyzed using different concentrations of H2SO4, temperatures and resident times. Hydrolysates were tested for xylose and glucose yield using a spectrophotometer Hydrolysates were then fermented at room temperature for different time duration using Saccharomyces sereviciae. Hydrolysis and fermentation processes were modeled and optimized using the RSM. A laboratory distiller was used to purify the bioethanol obtained, and the proximate composition and fuel properties were determined. Results showed that the feedstock had a composition of 74.33 % holocellulose, (57.44 % α-cellulose and 16.89 % hemicelluloses), 15.87 % lignin and 5.57 % ash. RSM polynomial of the quadratic form adequately expressed the relationship existing between process variables and yield of glucose, xylose, and bioethanol with R2 and SEE ranging from 0.963 to 0.993 and 0.121 to 2.501, respectively. Optimum glucose and xylose yield was 34.643g/L and 18.471g/L, at 1.196 and 1.195% acid load hydrolysis for 26.924 and 21.578 mins at 160.407 and 160.071oC, respectively. Optimum bioethanol yield of 32.838 g/L was obtained at 72.933h and 86.15% fermentation efficiency. The bioethanol had 97.68 % purity, 0.03 % ash, 0.42 % moisture content, 5.05 mg/L acidity, and 6.61 pH. The fuel properties were 791.13 kg/m3 density at 15oC, 1.67 mm/s2 viscosity at 40oC, 124 Octane Number, 13.043 kPa vapour pressure, 12.8oC flash point, 79 - 101oC distillation temperature range, 358oC auto-ignition, 29.16 MJ/kg calorific value, and 589.51oC drivability index. Proximate composition of the bioethanol satisfied the ASTM D4806 specification, its fuel properties met the International Standard, therefore, it can be blended with pure petrol for use in spark ignition engines.
OTHER EFFECTIVE AREA BASED CONSERVATION MEASURES (OECM’s) IN OSUN STATE: A DELPHI STUDY TO MITIGATE CLIMATE CHANGE.
Other Effective Conservation Measures (OECMs) are crucial for both sustainable biodiversity use and climate change mitigation. OECM sites in Osun State were identified as a measure for biodiversity conservation using delphi research, an organized method intended to extract the insights of experts. This paper identified 14 OECM in the study area, using the global positioning system receiver to obtain geographic coordinates. The landforms and associated ecosystems were captured through direct field observations and photographs while the assessment of meeting up with the OECM standard was done using the CBD Criteria, out of which only 8 sites met the CBD criteria. The study came to the conclusion that OECMs offer a worldwide framework for identifying, enhancing, and supporting additional designations of conservation areas. Additionally, they fortify the governance and management systems now in place. OECMs help achieve CBD Aichi Target 11, according to the study. It also suggested that policies boost the legitimate authorities' ability to govern in order to promote OECMs.
HEAVY METALS ACCUMULATION IN CATFISH AND HUMAN HEALTH RISK ASSESSMENT OF IKPOBA RIVER
A research of heavy metals concentration in fish samples collected from Ikpoba River, Benin City, during two months of March and July, 2024. The accumulation of heavy metals in fish is a significant concern due to their tendency to accumulate in fish tissues. Results from Atomic Absorption Spectrophotometer (AAS) analysis showed the presence of all six selected heavy metals (Iron, Chromium, Zinc, Lead, Copper, and Cadmium) in the fish species Clarias spp. However, concentrations were determined from the two fish tissues. In the liver, Fe, has the highest concentrations while Pb shown the lowest concentrations. The trend is as follows; Fe>Zn>Cr>Cu>Cd>Pb. In the gills, Fe, also has the highest concentration while Cu has the lowest concentrations. The order of the concentration in gills was as follows: Fe>Zn>Cd>Cr>Pb>Cu. The accumulated concentrations of heavy metals in liver is 7.19ppm higher than the gills 4.29ppm. The selected heavy metals for both tissues exceeded the maximum limits set by the WHO and FAO, except for Zinc and Copper in fish samples. This may result to chronic illness and cause potential damages to the population. Therefore, precautionary measures and continuous monitoring of Ikpoba River is necessary.
APPLICATION OF GEOSPATIAL TECHNOLOGY IN ASSESSING URBAN EXPANSION IN BENIN AND ITS ENVIRONS – IMPLICATION ON CLIMATE CHANGE
Effective monitoring of urban expansion hits serious difficulties and equally raises great questions for the future. The depletion of the natural vegetation leading to the altering of the ecology of Benin City and its Environs is of serious concern. To ascertain the extent of the aforementioned, this study applied the use of geospatial technology in assessing urban expansion in Benin and its environs. The result revealed that in 1987, forest occupied 56045.37 hectares, disturbed forest 83314.01 hectares, cultivated land 63419.92 hectares and urban land 35446.21 hectares, while in 2024 forest cover declined to 27917.74 hectares, disturbed forest 46956.81 hectares, cultivated land 76852.94 hectares and urban land 86498.02 hectares. On the overall, between 1987 and 2024 forest and disturbed forest were lost by 34.6% and 23.6% respectively, while cultivated land gained 8.7% and urban land 33.1%. This study revealed that urban expansion has severely impacted negatively on natural environment as a result of the spatial spread of urban land use over vegetation contributing to Global Warming and Climate Change. Based on the findings, there is need for conservation and management of existing land fragments in the study area. Alternative source of livelihood for the vulnerable groups should be provided by government as well.
ASSESSMENT OF HOUSEHOLD FOOD WASTE AS A POTENTIAL FEEDSTOCK FOR DECENTRALISED BIOENERGY PRODUCTION IN OKUOKOKO, DELTA STATE, NIGERIA
Household food waste poses persistent environmental challenges in rapidly urbanising communities, yet its relevance to decentralised bioenergy systems is rarely integrated into environmental assessments. This study examined food waste generation patterns, handling practices, and infrastructural conditions in Okuokoko, Delta State, Nigeria. Data were collected using a structured questionnaire administered to 250 households and analysed using descriptive statistics and reliability testing. Results indicate that 77.2% of households generate food waste daily, reflecting a temporally stable organic waste stream. Food waste generation is driven mainly by preparation-related losses (48.4%), followed by over-preparation (22.4%), weather-related spoilage (16.0%), and over-buying (8.8%). Disposal practices are predominantly unsustainable, with 57.2% of households using open dumpsites and 30.8% practising open dumping, while only 47.6% utilise waste collection services. Infrastructure constraints are evident, as 48.8% lack access to approved dumpsites. Although 58.0% report general waste management awareness, only 49.2% recognise food waste recycling, indicating a significant awareness gap.
IMPROVED (SPER) DESIGN WITH SOLAR-DRIVEN AIRFLOW AND CONTROLLED WATER CIRCULATION FOR REDUCED POSTHARVEST LOSSES IN SEMI-ARID OFF-GRID SETTINGS
Off-grid communities in Borno State face persistent challenges in preserving perishable food commodities due to high ambient temperatures, low relative humidity, and unreliable electricity supply. These constraints result in significant postharvest losses, weaken local food security, and limit the economic viability of smallholder farmers and informal food vendors. Conventional refrigeration systems, particularly vapor-compression technologies, are largely unsuitable in such contexts because of their high energy demand, dependence on continuous grid power, and environmental concerns associated with synthetic refrigerants. This study examines the viability and performance potential of a Solar-Powered Evaporative Refrigerator (SPER) as a sustainable cooling solution for off-grid environments. Constructed primarily from locally available, low-cost materials, the system was designed for autonomous operation, environmental sustainability, and scalability. Field testing under representative semi-arid conditions (ambient temperatures of 32–41 °C and relative humidity of 18–35%) demonstrated a maximum internal temperature reduction of up to 12 °C, alongside increased internal relative humidity suitable for fresh produce storage. Performance evaluation showed that the SPER reduced tomato spoilage by approximately 75% over a 72-hour storage period, significantly outperforming conventional non-insulated Zeer pots. Thermal analysis revealed that the combined effects of clay-based insulation, sustained fibre saturation, and solar-driven airflow were critical in stabilizing internal temperature and humidity levels, while maintaining low water and energy consumption. Overall, the findings confirm the SPER’s potential as a low-energy, decentralized refrigeration technology for resource-limited, off-grid settings. Its adaptability to tomatoes and other perishable commodities offers a practical pathway to reducing postharvest losses, improving food security, and promoting environmentally friendly cooling solutions in semi-arid regions.
ENVIRONMENTAL DEGRADATION, LIVELIHOODS, AND HEALTH IMPACTS OF OIL EXTRACTION ON MARITIME RESOURCES IN BRASS LGA, NIGER DELTA, NIGERIA
Environmental degradation from oil extraction poses significant threats to coastal livelihoods in the Niger Delta, yet integrated assessments linking ecological impacts to household well-being remain limited. This study investigates the socio-ecological consequences of oil pollution in Brass Local Government Area, Bayelsa State, Nigeria. Specifically, it assesses patterns of oil-induced environmental degradation, examines impacts on fisheries and mangroves, and analyzes livelihood and health outcomes for coastal communities. Two hypotheses were tested: (1) oil extraction significantly affects maritime resources, and (2) repeated exposure to oil spills negatively affects livelihoods and health. Data were collected from 300 respondents using structured questionnaires and supplemented with secondary spill records. Analyses employed descriptive statistics and multiple linear regression. Results indicate that frequent oil spills, primarily from illegal bunkering and pipeline failures, degrade fisheries, mangroves, and water quality, leading to reduced fish catch, loss of income, health challenges, and displacement. The study recommends stricter monitoring of oil infrastructure, ecological restoration, livelihood support programs, and risk communication to enhance community resilience and sustainable resource management.
Post-Remediation Environmental Monitoring of Surface Water and Sediments at Olero Jacket 43, Niger Delta, Nigeria
Post-remediation environmental monitoring is essential for verifying whether clean-up objectives have been achieved following oil spill response activities. This study assessed surface water and bottom sediment quality at Olero Jacket 43, Niger Delta, Nigeria, after remediation, using a compliance-based monitoring approach. Surface water and sediment samples were analysed for physicochemical parameters, petroleum hydrocarbons, and selected heavy metals. Results were summarised using descriptive statistics and compared with applicable regulatory guidelines. Surface water parameters, including total petroleum hydrocarbons and total hydrocarbon content, were within regulatory limits, indicating minimal residual contamination. Sediments showed acidic and organic-rich conditions typical of swamp environments, while hydrocarbon concentrations remained below regulatory target and intervention values. Heavy metal concentrations were generally low, with only minor cadmium enrichment observed below intervention thresholds. Overall, the results confirm that remediation objectives were achieved at the time of monitoring and highlight the importance of structured post-remediation monitoring for environmental management and regulatory assurance
Game-Theoretic and Adaptive Pricing for Residential P2P Solar Microgrids in Northern Nigeria
Reliable electricity access remains a major challenge in northern Nigeria, particularly in conflict-affected areas such as Maiduguri, where prolonged grid outages have increased dependence on decentralized energy systems. Peer-to-peer (P2P) energy trading and renewable microgrids present promising pathways for improving energy access, but their effectiveness relies on appropriate pricing mechanisms and active prosumer participation. This study models and evaluates a residential P2P microgrid situated in the 1000 Housing Estate, Maiduguri, comprising seven households, including one prosumer equipped with a 10kW solar photovoltaic (PV) system and a 40 kWh battery energy storage system (BESS). Using real household load data and a Python-based simulation environment, the study assesses PV generation feasibility, storage performance, P2P surplus allocation, and the economic impacts of three pricing schemes: Fixed-Rate, Adaptive Time-of-Use (ATOU), and Game-Theoretic (GT) pricing. Results show that the PV–BESS system reliably meets 100% of household energy demand with zero unmet load, generating 71.7 kWh/day of surplus energy for P2P distribution. A demand-weighted allocation mechanism achieves equitable sharing of prosumer surplus among households. Cost analysis indicates that GT pricing reduces total system cost by 7.4% relative to the Fixed-Rate tariff and provides the best balance between efficiency and fairness. Although ATOU yields the lowest overall cost, GT pricing demonstrates superior equity and responsiveness to household behavior, as evidenced by Gini coefficients, Lorenz curves, and violin plot distributions. The findings demonstrate that decentralized pricing and P2P trading can significantly improve energy affordability, fairness, and reliability in underserved communities. The study recommends the deployment of smart metering infrastructure, prosumer financing mechanisms, simplified licensing frameworks for P2P trading, and community-based governance structures to support scalable decentralized energy markets in Nigeria.
decentralized energy systems; peer-to-peer (P2P) energy trading; game-theoretic pricing; solar photovoltaic (PV) microgrid; battery energy storage system (BESS); adaptive time-of-use (ATOU) tariffs; energy equity and fairness; Nigerian Electricity Act 2023.
Electrical Engineering; Energy Systems; Renewable Energy; Sustainable Development and Energy Policy
EFFECTS OF ENVIRONMENTAL GEOMETRY ON WINDFLOW FOR ACTIVATING NATURAL VENTILATION IN BUILDINGS
Natural ventilation is hugely reliant on microclimatic conditions of an environment. In urban setting, this is often influenced by wind movements and air temperatures. The correlation between building heights and their proximity to each other and presence of physical structures that form the urban geometric elements are known to influence the incoming and outgoing wind speeds. This in turn impacts on the quantity and quality of air available for wind driven natural or hybrid ventilation. In this paper, field studies were carried out on selected building and its immediate surroundings within Baze University Campus in Nigeria. This study aims to identify and evaluate the behaviors of air flow as well as analyze the impacts of environmental geometric elements on the natural ventilation potential within the environment. For this purpose, a field survey was conducted to generate data regarding the microclimatic conditions in the study area. The study utilized both observatory analysis and simulation to analyze and describe the conditions measured. The general conclusion is that the surrounding street elements like trees and landscaping structures prevail in the diversion and consequent reduction of wind speed needed for natural indoor ventilation.
Housing Adaptation to Climate Change: A Critical Review of Resilient Architectural Practices and Renewable Energy Solutions
The built environment is a critical frontier for climate change mitigation and adaptation, with residential buildings accounting for a substantial portion of global energy consumption and greenhouse gas emissions. This paper presents a critical review of contemporary literature (2020-2025) synthesizing advancements in climate-resilient housing through integrated architectural and renewable energy solutions. A systematic analysis of 51 studies examines three core areas: passive and active architectural design for thermal resilience; the role of decentralized renewable energy in enhancing autonomy; and the socio-technical, policy, and governance dimensions of implementation. The review identifies a paradigm shift from static efficiency toward dynamic, adaptive building systems, highlighting the efficacy of bioclimatic design, smart materials, and AI-driven management. Decentralized solar energy is underscored as fundamental for decarbonization and energy security, though its success depends on supportive policies, community engagement, and equitable finance. Persistent gaps are noted, including the need for holistic lifecycle assessments, scalable models for low-income contexts, and stronger integration of technical and social equity approaches. The review concludes by advocating for a transformative shift toward adaptive, regenerative, and just residential environments.
IMPACT OF ADDITION OF TITANIUM DIOXIDE (TiO2) NANO PARTICLE ON THE DIELECTRIC PROPERTIES OF BIODIESEL EXTRACTED FROM JATROPHA OIL
Vegetable oils are gaining increasing attention as sustainable substitutes for conventional mineral oils in electrical insulation applications due to their biodegradability, renewability, and favorable thermal characteristics. Among these alternatives, Jatropha curcas oil has demonstrated promising dielectric properties, particularly adequate electrical breakdown strength for high-voltage applications. However, there remains limited understanding of the dielectric behavior of Jatropha biodiesel modified with metal oxide nanoparticles, as most existing studies focus on crude or refined oils and employ narrow or unsystematic nanoparticle loadings, with insufficient correlation between structural characteristics and dielectric performance. In this study, the effect of titanium dioxide (TiO₂) nanoparticle incorporation on the dielectric properties of biodiesel derived from purified Jatropha curcas oil was systematically investigated. The crude oil was first purified and transesterified to obtain biodiesel, after which TiO₂ nanoparticles were dispersed at concentrations ranging from 0.1 wt.% to 0.5 wt.% in increments of 0.1 wt.%. Structural, elemental, and molecular characterizations of the crude oil, biodiesel, and nanoparticle-modified samples were conducted using Scanning Electron Microscopy (SEM), X-ray Diffraction (XRD), X-ray Fluorescence (XRF), and Fourier Transform Infrared Spectroscopy (FTIR). Dielectric parameters, including dielectric constant (ε′), dielectric loss (ε″), and dissipation factor (tan δ), were measured over a range of temperatures using a digital LCR meter. The results demonstrate that the incorporation of TiO₂ nanoparticles significantly enhances the dielectric performance of Jatropha biodiesel by reducing dielectric losses and improving polarization stability. These findings highlight the potential of TiO₂-modified Jatropha biodiesel as an environmentally friendly and high-performance insulating fluid for high-voltage and high-temperature electrical applications.
Biodiesel, Vegetable oil, Jatropha oil, Titanium Dioxide (TiO2)
NEIGHBORHOOD-SCALE ANALYSIS OF URBAN GROWTH AND LANDSCAPE TRANSFORMATION IN RIKKOS AND LAMINGO, JOS NORTH, NIGERIA USING REMOTE SENSING AND GEOGRAPHIC INFORMATION SYSTEM (GIS)
Rapid urbanization in sub-Saharan Africa is changing land use and land cover (LULC) patterns, with significant implications for ecological sustainability and spatial planning. This study assessed LULC dynamics in Rikkos and Lamingo, Plateau State, Nigeria, between 2014 and 2024, to understand spatial patterns of urbanization and land degradation. Multi-temporal Landsat 8 OLI imageries (30 m spatial resolution) were analyzed using supervised classification (maximum likelihood algorithm) and post-classification comparison within a GIS framework. Five major LULC categories: built-up, farmland, vegetation, rock outcrop, and water body were identified and classified. The classification achieved an overall accuracy of 94.2% and a Kappa coefficient of 0.90, confirming its strong reliability. Results revealed a substantial increase in built-up areas (+54.13%) and rock outcrops (+414.77%), largely at the expense of farmland (−37.43%) and vegetation (−50.15%), while water body showed minor change (−13.73%). These shifts reflect intense anthropogenic pressure, rapid urban expansion, and progressive land degradation. The study emphasizes the pressing need for integrated land-use planning, afforestation, and the reclamation of degraded areas to foster sustainable environmental management and enhance ecosystem resilience. The findings provide a spatial basis for policy formulation aimed at curbing uncontrolled land conversion in rapidly urbanizing regions of sub-Saharan Africa.
GC-MS PROFILING, ANTIMICROBIAL, ANTIOXIDANT AND ANTI-INFLAMMATORY ANALYSIS OF THE N-HEXANE EXTRACT OF THE SEEDS OF RAPHIA HOOKERI OBTAINED IN DELTA STATE
Raphia hookeri is widely employed in African traditional medicine for diverse therapeutic purposes; however, its bioactive potential remains inadequately investigated. This study examined the chemical composition of the n-hexane seed extract of Raphia hookeri and assessed its antioxidant, antimicrobial, and anti-inflammatory activities. Preliminary phytochemical analysis revealed the presence of terpenoids, phenolic compounds, sterols, and cardiac glycosides. Antioxidant evaluation using the DPPH radical scavenging assay demonstrated notable antioxidant activity, indicating the strong bioactive potential of the seed oil. The antimicrobial activity of the extract was tested against Staphylococcus aureus, Helicobacter pylori, Escherichia coli, Candida albicans, and Candida krusei. The extract exhibited pronounced antimicrobial efficacy against all tested organisms, with zones of inhibition ranging from 18 to 25 mm. Anti-inflammatory assessment showed a maximum inhibition of 60.15% at a concentration of 500 µg/mL, compared to 89.13% inhibition obtained for diclofenac used as the reference drug. The minimum inhibitory concentration (MIC) for the extract was determined to be 2.5 mg/mL. These findings provide scientific support for the therapeutic relevance of Raphia hookeri seed oil and highlight its potential application in pharmaceutical, nutraceutical, and industrial formulations aimed at developing sustainable and affordable health solutions.
EFFECT OF EXTREME CLIMATE ON HUMAN PHYSIOLOGICAL DISCOMFORT IN JOS METROPOLIS, PLATEAU STATE
Amid rising global climate concerns, Jos Metropolis in Nigeria, a high-altitude city historically known for temperate conditions, now experiences abrupt temperature fluctuations (“Jos weather”) that induce significant physiological discomfort. This study investigated (i) specific weather conditions causing discomfort, (ii) the nature and extent of discomfort during extreme heat/cold, (iii) the most affected demographic groups, and (iv) coping strategy effectiveness. A descriptive survey design was adopted targeting 1,101,300 residents of Jos North and South LGAs (NPC, 2022). Using Taro Yamane’s formula, 400 respondents were selected via stratified random sampling. A validated questionnaire (Cronbach’s α = 0.818) and Landsat-derived LST analysis (2014–2024) were employed. Results revealed extreme heat and cold spells as primary drivers, causing respiratory issues, dehydration, and joint pain, worsened by urban expansion (+7.474 km² built-up area). The elderly are most vulnerable, with significant demographic differences (ANOVA F(3,379) = 6.247, p = 0.001) and a strong climate-discomfort relationship (r = 0.672, p < 0.001). Current coping strategies offer only moderate relief. The study recommends portable fans, insulated clothing, cooling centres, N95 mask distribution, GIS-based vulnerability mapping, and aggressive green infrastructure development to mitigate escalating health risks in Jos Metropolis.
Copyright (c) 2025 International Journal of Renewable Energy and Environment https://creativecommons.org/licenses/by-nc/4.0
ENVIRONMENTAL IMPACT OF WASTE LUBRICATING OIL ON SOIL QUALITY IN AUTOMOBILE WORKSHOPS IN DELTA STATE
This study assessed the impact of waste lubricating oil (WLO) management on soil quality in automobile workshops across three local government areas in Delta State, Nigeria. Soil samples were collected using a soil auger from five sites in Uwvie, Warri, Oghara and Sapele automobile workshops. Physicochemical and heavy metal analyses were conducted to evaluate contamination levels. Results showed moderately acidic soils (pH 4.60–7.20) except WARS1, which was slightly basic. Cadmium concentrations exceeded WHO limits, while heavy metals followed the trend Cr > Zn > Pb > Cd. Total petroleum hydrocarbons (TPH) were high (724.09–8630.39 µg/kg), indicating hydrocarbon contamination. ANOVA showed significant variation only in Total Organic Carbon (TOC%) and n-hexadecane, while PCA explained 96% of the dataset variance. The TPH contamination trend was WARS2 > SAPS2 > WARS1 > OGHS1 > SAPS1. The study concludes that improper WLO disposal significantly degrades soil quality, posing ecological and sustainability risks.
WEIGHT OPTIMIZATION OF 3D PRINTED PLATE SKID LANDING GEAR FOR IMPROVED ENERGY EFFICIENCY IN FIXED WING UAVS
This study details the structural optimization of a 3D-printed plate skid landing gear for fixed-wing unmanned aerial vehicles (UAVs) to improve flight endurance and operational efficiency through weight reduction. The study integrated Topology Optimization (TO) with Additive Manufacturing (AM) techniques, using ANSYS Mechanical for Finite Element Analysis (FEA) and fluid-structure interaction (FSI) simulations to ensure structural integrity under both ground and aerodynamic loads. Topology Optimization revealed the minimal load-bearing regions, enabling targeted material removal while maintaining the exterior airfoil shape. The optimized design achieved a 9.6% weight reduction (from 88.28 g to 79.80 g). Structural performance remained robust: maximum equivalent stress increased negligibly (0.84%), and reduction in factor of safety was minimal. Successfully fabricated using Fused Deposition Modeling (FDM), the new design also reduced production time by 1.89%. This research confirms that the synergy of TO and AM is a viable pathway for developing lighter, more energy-efficient UAV components, and this methodology can be extended to optimize other UAV parts and aerospace structures.
LAND USE/LAND COVER TRANSITIONS IN BENIN CITY AND IMPLICATIONS FOR MUNICIPAL SOLID WASTE MANAGEMENT
Benin City has witnessed tremendous increase in urban activities over the years, mainly due population increase. In 2006, the city recorded a population figure of 1,085,892 with a growth rate of 2.8 percent. However, by 2022, the Nigeria Population Commission projected population figure for Benin City at 1,841,000 at a growth rate of 3.31%. With rapid population growth and soaring urbanization, the city is now grappling with increased wastes generation and the need for improved waste management. This present study investigated the changing pattern of Land use/ Land Cover (LULC) in Benin and implication for MSW management. Landsat 7 and 8 thematic satellite imagery datasets were used in this study, and was sourced from the United State Geological Surveys (USGS) Earth Explorer platform. The analysis was based on satellite imagery classification covering five time periods: 2000, 2005, 2010, 2015, and 2020, with projections extended to 2025. Result showed that built-up area has continued to progress remarkably throughout the study period, demonstrating Benin City's rapid urbanization. Starting from 1,171 hectares (4% of the total area) in 2000, the built-up area expanded to 2,133 hectares (7%) by 2005, representing an 82% increase within five years. This upward trend continued consistently, reaching 2,866 hectares (9%) in 2010, 3,544 hectares (12%) in 2015, and 4,346 hectares (14%) in 2020. The projected 2025 figure of 5,229 hectares (17%) indicates that built-up areas will constitute nearly one-fifth of the total land cover. This expansion has resulted in growing pressure on public infrastructure, including municipal authority’s capacity to effectively manage solid waste. Indiscriminate dumping of waste has implications for GHGs emission, pollution, leachate contamination with serious concerns for public health. This study recommends the implementation of compact urban development strategies to reduce the urban footprint per capita as well as the establishment clear urban growth boundaries to prevent sprawl into environmentally sensitive areas, including illegal disposal of MSW in these areas of the city.
ASSESSMENT OF AIR QUALITY AND NOISE LEVEL AROUND UNIVERSITY OF BENIN UGBOWO CAMPUS MAIN-GATE, BENIN CITY, EDO STATE NIGERIA
This study investigates the air quality and noise levels around the Main Gate of the University of Benin, Ugbowo campus, Benin City, Edo State, Nigeria, to assess the environmental conditions. Information on Particulate Matters (PM2.5, PM10), Formaldehyde (HCHO), Total Volatile Organic Compounds (TVOCs), carbon monoxide (CO) and carbon dioxide (CO2) and noise levels were obtained. The results indicated that air quality, PM2.5, Noise level exceeded the permissible limits set by WHO while CO exceeded NESREA permissible level. These findings highlight the need for enhanced environmental management and regulatory measures to improve air and noise quality around the area. The study underscores the importance of ongoing monitoring and the implementation of pollution control strategies to mitigate the adverse health effects associated with prolonged exposure to poor air and noise quality.
COMPARATIVE PERFORMANCE ANALYSIS OF MONOCRYSTALLINE, POLYCRYSTALLINE, AND THIN-FILM SOLAR PANELS UNDER VARYING SOLAR IRRADIANCE IN ABAKALIKI, EBONYI STATE, NIGERIA
This study investigated the comparative performance of monocrystalline, polycrystalline, and thin-film solar panels under varying solar irradiance and temperature conditions. The study employed an experimental design in which photovoltaic panels were exposed to natural sunlight during a seven-day rooftop experiment in Abakaliki, Ebonyi State, Nigeria, with measurements of solar irradiance, ambient temperature, voltage, current, and power output. All the panels were operated at a uniform tilt equal to the site’s latitude and the same orientation, with identical cleaning and maintenance procedures to ensure consistent solar exposure. Results show that monocrystalline panels achieved the highest mean power output (53.80 ± 15.05 W), voltage (18.49 ± 0.20 V), and current (2.91 ± 0.80 A), outperforming polycrystalline (45.69 ± 14.11 W; 17.73 ± 0.21 V; 2.57 ± 0.77 A) and thin-film panels (32.03 ± 10.24 W; 16.03 ± 0.34 V; 2.00 ± 0.65 A).The study concluded that monocrystalline panels have more technological advantage due to their higher and more consistent power output, voltage stability, and responsiveness to varying solar irradiance, making them better suited for energy-demanding applications, especially in warm, high-irradiance regions like Nigeria.
MODELING SLOPE AND ASPECT INFLUENCE ON LANDSCAPE MORPHOLOGICAL CHANGE IN NDELE, RIVERS: A GIS-BASED ASSESSMENT
This study examines the complex relationships between slope, aspect, and landscape evolution. The study analyzed how slope and aspect as fundamental topographic factors significantly influence landscape evolution. The primary data was derived from extraction of DEM resolution 30m×30m LANDSAT TM– imagery downloaded from United State Geological Survey. The secondary data were gotten from simulation results carried out with digital elevation model (DEM) using Landscape Process Modeling at Multi dimensions and Scales (LAPSUS); a GIS-based Landscape Evolution Model. The findings of the study showed that the interaction between slope and aspect shaped Ndele landscape through influencing erosion patterns, landform morphology, and ecosystem dynamics. Slope angle controls erosion rates as shown that steeper slopes occur in the Northern regions of Ndele while lower, gentler slope are continually worn down with the lowest value occurring in 2016 at 40.05. Conclusively, the study findings infer that there is an inverse relationship between slope angle and soil erosion which led to structural change in the areas landscape.
FRACTIONAL DISTRIBUTION OF SOIL CONTAMINATED WITH LEAD NITRATE AND CADMIUM NITRATE USING SEQUENTIAL EXTRACTION METHOD
A separate pot experiment was conducted to compare the metal uptake of soil spiked with amount of lead nitrate (Pb0- 0 mg/kg, Pb1- 1000 mg/kg, Pb2- 500 mg/kg, Pb3- 250 mg/kg, Pb4- 125 mg/kg, Pb5- 62.5 mg/kg), cadmium nitrate (Cd0- 0 mg/kg, Cd1- 1000 mg/kg, Cd2- 500 mg/kg, Cd3- 250 mg/kg, Cd4- 12 5mg/kg, Cd5-62.5 mg/kg) and the combination of the two salts using maize plant. The experiment was carried out under a greenhouse condition for ten weeks; the maize cob was harvested and analysed with Atomic Absorption Spectroscopic (AAS). Sequential extraction was used to fractionate the spiked soils into five operationally defined groups: Exchangeable, Carbonate, Fe-Mn oxide, Organic and residual. The Organic fraction was the most abundant pool for the soil spiked with lead nitrate while Carbonate is the most abundant for that spiked with cadmium nitrate and the results obtained from the combination of the two salts indicated that Organic fraction was the most abundant. Metal distribution in the different chemical fractions in these soils depends on the respective total metal concentration used to spiked the soil.
Comparative Analysis of the Performance of Batteries
This study presents a comparative modeling and performance analysis of four major battery chemistries Lead–acid, Lithium-ion, Solid-state, and Flow using MATLAB/Simulink and Simscape. A unified equivalent circuit model (ECM), comprising an open-circuit voltage source, ohmic resistance, and two RC branches, was implemented as a baseline framework to ensure consistency across chemistries. Chemistry-specific extensions were incorporated, including the Shepherd–Peukert model for Lead–acid, a Single-Particle Model (SPM) for Lithium-ion, an extended SPM with interfacial resistance for Solid-state, and coupled tank–stack–channel dynamics for Flow batteries. Experimental OCV–SOC (Open-Circuit Voltage vs. State of Charge) data, diffusion coefficients, and kinetic parameters were integrated to enhance fidelity, while degradation sub-models such as SEI growth, Peukert aging, interfacial resistance, and electrolyte imbalance enabled lifecycle projections. Standardized test protocols comprising constant-current discharges, dynamic load cycles, temperature sweeps, and cycling tests were applied to evaluate voltage–SOC behaviour, round-trip efficiency, thermal rise, and cycle life. Results indicated that Lithium-ion and Solid-state deliver superior energy density and efficiency, Lead–acid remains cost-effective but cycle-limited, and Flow batteries achieve exceptional lifetime with scalable power–energy decoupling. The unified framework provides a reproducible methodology for battery evaluation, offering valuable insights for mobility, stationary storage, and grid-scale applications.
Assessing Grid Stability Under Renewable Energy Penetration Using Data-Driven Simulations
This study develops a simulation framework based on a modified IEEE 14-bus network in MATLAB/Simulink to evaluate stability under renewable energy integration. Hourly meteorological data from the Nigerian Meteorological Agency (NiMet, Jan–Dec 2024) were used to model residential and commercial loads alongside solar irradiance and wind speed. System performance was assessed at penetration levels of 10%, 50%, 70%, and 100%, using metrics such as voltage deviations, frequency fluctuations, and energy storage requirements. At 10% penetration, voltage and frequency remained within ±1.8% and ±0.02 Hz, respectively. At 50%, deviations increased to ±4.5% and ±0.08 Hz, while at 100% they exceeded ±6% and ±0.15 Hz. Storage capacity needs also rose significantly, from 0.5 MWh to over 6.5 MWh. The results highlight the growing importance of scalable energy storage and advanced control measures for maintaining power system reliability under high renewable penetration.
COMPARATIVE YIELD AND ANALYSIS OF ALCOHOL FROM SELECTED AGRICULTURAL PRODUCTS
Alcohol was produced from cassava, sorghum, rice and maize by measuring 100 grams of each starch material sourced from the different agricultural products which were hydrolyzed using 6 M hydrochloric acid respectively. The resultant reducing sugar (glucose) solution were fermented using brewer’s yeast and then distilled to obtain alcohol (ethanol). The yield of alcohol was determined, which ranged from 19.40 – 7.00 %. Sorghum gave the highest yield of 19.40 % which rice gave least yield of alcohol of 7.00 %. The daily protein analysis of the fermenting liquor was irregular, however the daily glucose analysis showed a gradual decrease in the concentration of glucose as fermentation progresses.