Research Publications

Mathematical modeling of combustion characteristics of agricultural waste briquettes

2026-07-14T07:30:58Z

Mathematical modeling of combustion characteristics of agricultural waste briquettes Ondari, Brian; Kimutai, Stephen Kibet; Mukubwa, Emmanuel Wanyama Rapid population increase coupled with industrialization has led to rise in global energy demand leading to skyrocketing of energy prices. Diversification in energy resources is essential to reduce overdependence on certain resources. Agricultural wastes remain a promising energy resource to be exploited. Laboratory experimental analysis is time consuming and costly. This fueled the adoption of modelling as an alternative to laboratory analysis. Different models such as computational fluid dynamics (CFD), artificial neural network (ANN), and ANFIS fuzzy logic have been used by various researchers. Buckingham pie theorem together with MATLAB was used in this research to evaluate the properties and combustion characteristics of assorted agricultural wastes. The properties modelled were; porosity, density, shatter resistance, higher heating values, burnout time, burning rate, ignition time and efficiency. The factors that affect each of the properties negatively and positively were determined from the models. The significance of each property and characteristics were articulated. The limitations and assumptions of the models were also highlighted. It is recommended that further research incorporating artificial intelligence in the models needs to be exploited aid in reduction of experimental analysis costs and time. Other agricultural wastes which have not been characterized for need to exploited. This will further reduce overdependence on conventional resources such as fossil fuels which are not only getting depleted at an alarming rate but also led to environmental degradation.

Assessing power sector expansion and related emissions using the low emissions analysis platform: The case of Burundi in East Africa

2026-07-14T06:57:26Z

Assessing power sector expansion and related emissions using the low emissions analysis platform: The case of Burundi in East Africa Egide, Manirambona; Niyongere, Abraham; Ndayizeye, Martin; Bonaventure, Dusabe; Kaziri, Amissi Bob; Talai, Stephen M; Kimutai, Stephen Kibet Burundi anticipates rapidly growing electricity demand due to several evolving factors: the Government's plans to boost national GDP and position the country among emerging economies by 2040; high population growth; increasing demand for education and health facilities; and the high potential of coltan, nickel and other minerals expected to be exploited. All these goals are hindered by a significant shortfall in meeting the country's electricity needs. Despite the construction of numerous power plants aimed at improving the low electricity access rate, the country still requires considerable efforts to ensure sustainable and continuous development. Energy planning remains relatively underdeveloped in Burundi, highlighting the need to go beyond addressing the current deficit and develop a robust national electricity planning strategy. The Low Emissions Analysis Platform was used to investigate different power sector expansion scenarios and associated emissions, targeting the country's vision 2040. Three energy policies “efficient lighting (Ef-L), universal electrification (Un-El) and low CO2 emissions (LEm)”, established as tactical priorities for Burundi, were analyzed. The L-Em was evaluated in terms of CO2 Equivalent at the point of emissions using a 100-year Global Warming Potential. Results showed that the country's electricity demand is anticipated to continue increasing, from 180.4 GWh in 2015 to a projected 867.6 GWh in 2040 under a Business-As-Usual scenario. Households are expected to remain the largest consumers of electricity. The Ef-L policy could save 124.6 GWh. Under Un-El, households' electricity demand would reach 825.7 GWh by 2040, compared to 536.5 GWh under the Business-As-Usual scenario. By phasing-out all fossil-fired plants after 2030, the L-Em policy would require importation of significant amount of electricity, unless there is a higher deployment of renewable energy technologies than currently planned. High adoption of renewable energy sources, combined with the Ef-L policy, are strongly recommended in the country's national energy strategies

The Renewable energy food processings ustainability nexus: a PRISMA review of innovations, sustainability metrics and indicators

2026-07-14T06:33:42Z

The Renewable energy food processings ustainability nexus: a PRISMA review of innovations, sustainability metrics and indicators Mwewa, Chikonkolo Mwape; Kimutai, Stephen Kibet; Nzila, Charles; Bett, Ronald Kipkemoi; Washika, Tony; Mayen, Deng; Njurumba, Peter; Hensel, Oliver Renewable energy-based innovations and technologies play a crucial role in reducing postharvest losses and enabling low-carbon food processing, but their sustainability assessments remain fragmented and inconsistent due to variations in evaluation metrics. This review compiles studies on renewable energy–based food processing, including solar, photovoltaic, solar thermal, and hybrid systems. It highlights that most evaluations focus on technical and environmental performance, while economic, governance, and social aspects are less consistently addressed, often reported only qualitatively. Based on reported indicators, a five-pillar conceptual framework is proposed to organize sustainability assessment across technical, environmental, governance, economic, and social (TEGES) dimensions. The framework shows how sustainability indicators can be systematically structured from design and testing to modeling and implementation stages. A key contribution of this study is the introduction of proxies for governance and social sustainability, quantifiable factors like safety, usability, and ease of maintenance, that allow for early evaluation of governance and social significance even during laboratory testing. The synthesis highlights the need for standardized sustainability reporting by using consistent boundaries, functional units, and contextually relevant metrics. By establishing a structured conceptual framework, this work enhances the methodological foundation for integrated, transparent, and policy-relevant sustainability assessments within renewable energy–based food systems, aligning research methodologies with international reporting standards such as ESG and the Sustainable Development Goals (SDGs). Future research should focus on automating and standardizing sustainability assessments, as each metric links to a specific value. This will enhance the credibility and accessibility of evaluating the climate and sustainability impacts of renewable energy innovations in food processing, ultimately supporting sustainable green funding and food production.

Socio-economic burden of Rift Valley fever outbreak in a pastoralist community in Marsabit County, Kenya, 2018

2026-07-13T13:08:12Z

Socio-economic burden of Rift Valley fever outbreak in a pastoralist community in Marsabit County, Kenya, 2018 Mutiiria, Mathew Munyamaara; Gatongi, Peter; Oyugi, Elvis; Muturi, Mathew; Mwatondo, Athman; Chege, Bernard; Mungiiria, Juster Introduction: Rift Valley Fever (RFV) is an acute vector-borne viral zoonotic notifiable disease primarily of domestic animals. It causes significant economic impacts among livestock producers and consumers. An outbreak of RVF occurred in May-June 2018; Marsabit reported positive cases in humans and animals. The study described herd owners’ social demographic characteristics, estimated livestock mortality and quantified the direct and indirect monetary losses in Laisamis Sub-County. Methods: We conducted a cross-sectional study. Data was collected from 384 households. Direct and indirect costs were estimated using the economic model as described in Velthuis et al. (2008). Descriptive statistics were used to describe social-demographic characteristics. Economic burden incurred was the outcome variable. Results: Majority of the respondents were females (67.2%). Total direct and indirect economic burden/losses were 1,970,000 USD, cattle recorded the highest financial loss at 42.3% (832,850 USD) through mortality. Stormy abortions were the most common syndrome reported at 382(99%).No routine livestock vaccination against RVF. Young herd owners were more likely to suffer economic losses compared to the aged (>60 years of age). Male herd owners and those with formal education were less likely to experience financial loss at (OR=0.42, p-value < 0.0001) than female herd owners. Conclusion: A higher economic burden was associated with the RVF outbreak in Laisamis, particularly among female-headed households of younger age groups. Men had less odds of experiencing a financial burden compared to women. There is a need to vaccinate animals against RVF at the local level to reduce economic losses associated with an outbreak.