M.T. Oladiran

Mean global radiation captured by inclined collectors at various surface azimuth angles in Nigeria

The use of solar energy is well established for low-grade thermal applications such as water heating and purification. In many of the solar systems, the collector surface located in the Northern Hemisphere faces the true south direction. However, there are occasions in which the radiation received by the collector at various orientations is desirable, such as a collector incorporated with a tracking system. The data for such situations are not available for several solar farms in Nigeria. Consequently, in this study, the average global radiation on flat surfaces was determined for three zones in Nigeria. The total insolation was obtained while the surface azimuth angle was varied between 0° and 75° at 15° intervals. The results are presented for three inclinations of the collector surface, namely L - 10, L, and L + 10 degrees respectively.

Global Engineering Teams--A Programme Promoting Teamwork in Engineering Design and Manufacturing

Engineering graduates are expected to possess various competencies categorised into hard and soft skills. The hard skills are acquired through specific coursework, but the soft skills are often treated perfunctorily. Global Engineering Teams (GET) is a programme that promotes project-oriented tasks in virtual student teams working in collaboration with industry partners. Teamwork is a major success factor for GET as students always work in groups of varying sizes. A questionnaire-based survey of the 2008 cohort of GET students was conducted to assess teamwork, communication and conflict resolution among group members. The results confirmed that deliverables are readily achieved in teams and communication was open. A challenge of using virtual teams is the availability of high-speed Internet access. The GET programme shows that it is possible to deliver engineering design and manufacturing via industry/university collaboration. The programme also facilitates multidisciplinary teamwork at an international level.

Total solar radiation received at various collector inclinations

Solar energy is finding wide application via several energy-saving devices and systems. Its use, especially in rural areas, can often be limited by the non-availability of complete information on insolation data. In this investigation, both the mean extraterrestrial and terrestrial radiations were calculated for three zones in Nigeria. These zones were assumed to be dependent mainly on the latitude, L. The isotropic model was employed for the computation of the diffuse and ground reflected components of radiation. Consequently, the total insolation was obtained for various inclinations of the collector surface. It was found that three solar energy seasons exist for each zone. For maximum total incident radiation, a different collector inclination is ideal for each solar energy season. However, for all year round applications, a fixed inclination varying between L and (L+10) degrees is recommended.

Energy applications in botswana

Abstract Botswana depends heavily on imported petroleum products for all premium applications. However, there is an abundant reserve of coal and other alternative sources of energy. This paper presents the energy trends and the various options for harnessing the resources. The importance of energy conservation is also discussed.

Blackboard as a Tool for Peer Learning and Interaction for Engineering Students

The purpose of this study was to evaluate the learning experiences of mechanical engineering students who used Blackboard technology at the University of Botswana. The results presented are based on the application of the technology in two courses offered to Year 3 students. As the results of this study were encouraging it is recommended that more courses in the mechanical engineering programme should migrate to blended mode of instruction delivery.

Assessment of solar-coal hybrid electricity power generating systems

Botswana currently depends on electricity generated from coal-based power plant or electricity supplied from the border in South Africa. The country has good reserves of coal and the solar radiation is sufficiently high to make solar thermal attractive for generating electricity. The paper presents two conceptual coal-fired power station designs in which a solar sub-system augments heat to the feed heaters or to the boiler. The thermal and economic analyses showed enhanced system performance which indicates that solar power could be embedded into existing fossil fuel plants or new power stations. Integrating solar energy with existing or new fossil fuel based power plants could reduce the cost of stand-alone solar thermal power stations, reduce CO2 emissions and produce experience necessary to operate a full scale solar thermal electricity generation facility.

Modeling of technology adoption in Botswana

Purpose – The conceptualisation of technology adoption has largely been based on the Bass or some Bass-derived model – notably, the logistic model. Logistic-type models offer limited insights regarding the adoption process dynamics or the utility value of their results. The purpose of this paper is to outline an alternative technology adoption framework based on complex adaptive networks. Design/methodology/approach – An agent-based methodological approach is proposed. In it the actors, factors, goals, and adaptive learning influences driving solar energy technology adoption (SETA) process are first substantiated by empirical evidence gathered using field questionnaires and then incorporated in the simulation of a dynamic complex adaptive network of SETA. The complex adaptive network model is based on simple heuristic rules applied using a modified preferential attachment scheme within a NetLogo simulation environment. Findings – The interim results suggest an emergent network where prominent hub “driver”...

Evaluation of Solar Water Heating Systems in Botswana

This paper presents results of an assessment of several solar water units to determine causes of their malfunctioning. A survey of solar water heater (SWH) installations in the Gaborone area, Botswana was carried out to obtain performance characteristics of SWH in the local market. Extensive inspections were performed on both in-service and non-functioning units, problems were diagnosed and pragmatic solutions were proffered. The paper presents some of the discoveries made during the investigation, namely, several units did not last up to the payback period of say 10 to 15 years. The results obtained could provide guidance in selecting operating criteria and suitable system design for solar water heating applications.

Tracking Design Elements in a Mechanical Engineering Curriculum

Design activity is core to modern engineering practice. Some design experience is demanded by professional bodies that accredit degree engineering programmes (e.g. ABET and ECSA). The purpose of this paper is to track design related topics through the curriculum of the mechanical engineering degree programme at the University of Botswana. A questionnaire was designed and administered to staff teaching on the programme. The responses were used to map design components in the curriculum and assess the design experience of students. The results showed that design topics were delivered in various courses and the knowledge gained by students increased steadily from Year 3 to Year 5. Some observed deficiencies in the teaching of design included lack of industry recommended projects, negligible application of design software, and the use of only single discipline based problems (i.e. no multi disciplinary teaching approach). It was concluded that a programme review is needed to improve the pedagogy of design and enhance programme robustness. It is envisaged that the study will help in designing a new mechanical engineering curriculum to satisfy accreditation requirements.

Designing Architect’s Brief for a Faculty of Engineering

A team of academics produced a Design Brief (DB) to assist architects design a scholarly physical environment for modern engineering education and research. The information gathered from external and internal sources was used to define important themes that the buildings should reflect and hence to arrive at a list of the required spaces. Critical internal and external reviews and budget constraints led to a series of successive refinements of the DB. A design competition was organised for all interested architects in the country to select the architect for the project and consolation prizes were awarded to second and third finalists. The planned development will provide 17900 m2 and 25200 m2 net usable space and estimated gross building area respectively.