Biogas is a renewable energy that has many applications including cooking, lighting households among others. It is produced through the breakdown of organic matter in an air tight compartment through a biochemical process which is generally termed digestion. This technology involves various techniques through use of digesters or bioreactors and operational parameters which could be predicted and must be optimised. A 0.15m3 capacity fixed dome laboratory bioreactor was used to determine the ef...
Solid waste management is challenging and incineration technique is more preferred to other methods in reduction of mass and volume, removal of odour and energy recovery in both industrial and residential environments. The challenges facing residents at Njokerio, Ng’ondu and Green Valley areas included poorly designed open-wastes collection systems, exceeding incinerator loading rates, inappropriate operating temperature levels and inadequate design specifications. Objectives of this study ...
Sedimentation of irrigation canals is one of the major challenge that affects their hydraulic control and operation. The sedimentation reduces water conveyance capacity and may lead to overtopping in low land areas. A case in point is the Chókwè Irrigation Scheme (CIS) which has experienced sedimentation problems for decades. There is scanty information on water flow and sedimentation within the canals in the CIS which is crucial for proper management and operation of the scheme. To address...
Abstract: The potential of solar energy in addressing global energy challenges, particularly in regions like Ethiopia with abundant sunlight, cannot be overstated. This study investigates the potential of solar energy adoption, particularly through solar rooftops, as a solution to address energy challenges in regions with abundant sunlight, such as Ethiopia. Focusing on urban households in Harar town, Ethiopia, the study assess their readiness to adopt solar rooftops for electricity generati...
Abstract: The shortage of electricity in Ethiopia creates a huge gap between demand and supply, making individuals and organizations look for alternatives to obtain regular supply of power. Ethiopia has a vast potential for renewable energy resources like solar energy that have not fully utilized. Although solar energy is abundant, accessible, affordable, and ecologically and environmentally friendly, in rural Ethiopia the majority of households are still using pollutant kerosene for lightin...
Abstract study was conducted in West Usambara Mountains, Tanzania to assess stakeholders diverging interests and emerging resource use conflicts in apiculture with respect to natural resource management (NRM) by local communities. The study aimed at generating knowledge base for effective governance of NRM by farmers from which lessons could be drawn for guiding appropriate NRM. Participatory Rural Appraisal (PRA) tools including focused group discussion, questionnaire survey and participant...
Abstract: Finding faults and partial shadow conditions are the key challenges for photovoltaic (PV) system. Furthermore, by being aware of how many broken modules and strings there are, the power loss can be averted. Some studies are conducted in this project to address these issues in order to distinguish between faults and partially shaded conditions as well as the quantity of mismatched modules and strings for a dynamic change in irradiation. Based on a straightforward observation ...
This paper assesses the effect of direct and indirect factors on the shear performance of ultra-high performance fibre reinforced concrete beam containing coarse aggregate (UHPFRC-CA) using four point loading arrangement. The obtained results were used to categorize UHPFRC-CA beam's failure mode, establish the influence of key factors on shear performance, and develop UHPFRC-CA beam's compression zone resistance and first shear cracking load equations whose results were compared with those fr...
Abstract/Overview Virtual learning systems are becoming an increasingly common form of education due to the need for a platform that provides ability to connect people with required sets of skills, regardless of their location in the world. However, user satisfaction has always been a major factor in the success of software, regardless of whether the software is proprietary or freeware (such as open source software). Although user-centred designs are gaining recognition among virtual lear...
Abstract Arc-welding coatings are extensively employed within the informal sectors of many African countries to repair various machine components, such as gear teeth, machine shafts, bushings, and many others. In the pursuit of advancing steel component repair techniques, this study investigates the surface properties of mild steel plates coated with alumina using the Metal Inert Gas (MIG) welding process. Mild steel wire of diameter 1.6 mm, alumina particles of size 1 µm, and mild steel pl...
Abstract Access to safe water and sanitation is a basic human right and is enshrined in the sustainable development goal 6. Consequently, resources have been channeled towards development and improvement of water sources. Unlike surface water, the demand for groundwater is increasing due to its preserved quality, affordable development capital and drought resilience. Population density has resulted into entry of pollutants into aquifers because of reduced distance between the pollutants and ...
Abstract Geopolymer concrete (GPC) is a novel and environmentally friendly type of concrete that eliminates the use of cement, resulting in a significant reduction in carbon emissions and a more sustainable construction material. Alkaline activators are used in GPC to achieve rapid strength development. The most popular alkaline activators are sodium/potassium silicate and sodium/potassium hydroxide, which are known contributors to carbon emissions, hence limiting the advantages of GPC; ther...
Abstract Designing foundations, particularly highway pavements, on black cotton soil has consistently posed a delinquent for engineers, as structures supported by this type of black cotton soil are prone to unexpected cracking and settlement. The issue this study aims to solve is the lack of appropriate performance materials for use as road subgrade in regions with black cotton soil. This study aims to inspect if a mixture of silica sand and lime can be used to advance the mechanical propert...
Abstract In this research, comparative investigation of the effect of selected natural polymers with the chemically synthesis imported polymer on threaded assemblies was carried out. The investigation involved the extraction of rubber and cashew resin using the continuous tapping method and ackee aril resin by the soxhlet extraction method, respectively. Stabilization of resin density, pH and viscosity was carried out by the addition of ZnO in different weight percentage of 3, 5, 7, and 10% ...
ABSTRACT The use of solar energy through photovoltaic systems has seen rapid growth in recent years due to its environmental benefits and cost-effectiveness. However, one of the main challenges that PV systems face is the accumulation of dust and debris on solar panels, which can significantly reduce their efficiency. To address this problem, we propose the design and development of a solar cell cleaning robot. This project aims to create an autonomous robot capable of cleaning solar panels e...