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M.Sc. / South Africa is in the midst of an energy crisis. The national energy provider is unable to provide the capacity currently demanded in South Africa. Although the construction of new electricity plants is planned, it does not solve the immediate problem. A large amount of energy is used to provide thermally comfortable indoor environments using conventional methods such as air-conditioning units. Energy efficiency is an environmentally friendly solution for South Africans to reduce the demand for electricity. In the context of the current situation in South Africa, significance can be given to investigations that explore viable methods of reducing energy consumption in buildings, while maintaining or improving thermal performance through passive energy interventions. This study was conducted with the goal of quantifying and demonstrating technologies that simultaneously attempt to improve energy efficiency (through avoiding the use of energy intensive heating/cooling units) and improving the physical learning environment in prefabricated classrooms in South Africa, through the use of passive energy retrofits. This study forms one of the initial case studies conducted within the framework of the Enerkey Sustainable Megacities pilot programme. Reflective roof coatings and ceiling insulation were used to retrofit eight prefabricated classrooms at Garsfontein Primary School, Tshwane. Monitoring was performed of temperature conditions in two control and eight experimental classrooms. The resulting data were used to compare the thermal performance of the altered classrooms to the control classrooms. Empirical data sets included hourly average temperature readings in ten prefabricated classrooms and an externally located weather station. Average diurnal temperatures and temperature difference plots were created. A pre-retrofit questionnaire to determine occupants’ perceptions on the thermal indoor environments was distributed. Spot measurements of illumination levels in all ten classrooms were taken with a Lux meter. A cost-effectiveness analysis of the passive energy interventions was performed, using as a reference case an electrically powered air conditioning unit, specified to cool a 50 m2 classroom. Overall, the reflective roof coatings were not effective at reducing peak summer temperatures. A 50 mm thick plastic fibre insulation layer installed in the ceiling spaces consistently reduced peak indoor temperatures by ~2°C, while 50 mm thick expanded polystyrene ceiling boards were the most effective of the retrofits, consistently reducing peak indoor air temperatures by ~3°C. An analysis of the cost-effectiveness of passive interventions showed that, in comparison to the proposed alternative of installing electrically powered air-conditioning units, ceiling insulation is cost effective in varying extents, depending on the assumptions. However, in all cases considered, the cost advantage, expressed as Rand per degree Celsius comfort improvement, is considerable compared to the air conditioning unit. Light measurements indicated non-uniform illumination in the tested classrooms, from severe glare next to south facing windows, to dark areas well below minimum recommended levels. The overall illumination situation is unsatisfactory. Opportunities exist for improving illumination using passive and active energy efficient interventions. The hypothesis for this study was that passive energy interventions in prefabricated classrooms are energy- and cost-efficient means for improving the physical learning environment in South African schools. Ceiling insulation makes a valuable contribution towards improving indoor thermal environments in prefabricated classrooms. Ceiling insulation by itself, however, does not provide a comprehensive solution – the entire building envelope needs to be taken into consideration. A building energy digital simulation model could explore a range of interventions, to derive the overall most costeffective solution to improving indoor thermal environments in South African schools. Investigations of this nature will be conducted as part of the ongoing larger Enerkey project.

Student Number : 0420494F - MSc research report - School of Geography, Archaeology and Environmental Studies - Faculty of Science / Government reforms aim to provide free basic and affordable electricity in poor urban areas. However, the growing rate of urban poverty, limited development of energy infrastructure, the cost of modern services and fuel use culture further contribute towards the consumption of multiple fuel use. The diverse ways in which urban households utilise the available energy can make fuel transition very difficult to achieve. This research aims to investigate household energy consumption patterns in Diepkloof in order to understand the factors limiting a fuel transition from coal and wood to electricity. The analysis in this report uses data collected from the household survey in Diepkloof as well as key stakeholders in this field including the Soweto Electricity Crisis Committee and Eskom. The reason for using these two stakeholders was because SECC is a social movement activist group advocating free electricity while Eskom is the electricity service provider. Household data examines the range of fuels, factors affecting fuel choice and the attitude of people towards alternative energy sources. The two stakeholders help to critically assess the effectiveness of energy policy document supporting the supply of electricity to poor communities, including Diepkloof. This research concluded that there is no clear evidence that an energy transition is taking place in Diepkloof. Moreover, the results indicate that the energy policy has good intentions but there are still some difficulties with affordability, and culture or personal choice. As a consequence of the underlying problem, most poor households still rely on multiple fuels use for major thermal purpose such as cooking and heating.

Thesis submitted in fulfilment of the requirements for the degree of Master of Management in Finance & Investment in the Faculty of Commerce Law and Management Wits Business School, Johannesburg 2016 / This thesis reviewed research papers, reports, conference documents and policy documents that looked at financial models used to finance RE projects in Brazil, China, India and South Africa.The comparison between the financing models revealed the following; Both Brazil and China’s financing model is a centralised government led model which might not necessarily work in the South African context. The India decentralised model is similar to the South African model, with the exception that corporate finance is widely used in India and Project Finance in South Africa. Thus there are lessons to be learnt from each country, however no single country financing model was found to be suitable for South Africa. Accordingly, this paper therefore recommends that South Africa’s model be altered to incorporate project bonds. The use of these bonds in the current financial model will ensure that banks are able to lend to projects on short term basis; thus, managing their liquidity and their asset--liability effectively. Further, some institutional investors have shown an interest in funding projects at the construction stage, and the inclusion of project bonds would ensure that more of these investors play a role in financing projects. Key Words GDP-Gross Domestic Product; GW- Gigawatts; DoE-Department of Energy; REIPPPP- Renewable Energy Independent Power Producer Procurement Programme; BEE-Black Economic Empowerment; RE-Renewable Energy; SSA-Sub Saharan Africa; PPA-Power Purchase Agreement; FIT-Feed In Tariff; DFIDevelopment Finance Institution; MDB-Multilateral Development Bank / GR2018

Energy use in buildings is an important contribution to global CO2 emissions and contributes to global warming. In recent years, there has been concern about creating energy efficiency buildings, green buildings and healthy buildings but this development needs guidance by multidisciplinary scientists and experts. Since energy saving can influence the indoor environment in different ways, epidemiological research is needed in different climate zones to evaluate the health consequences of making the buildings more energy efficient. Epidemiological studies and modelling studies are available on health effects and indoor effects of energy conversation, improved thermal insulation, increased air tightness and creating green buildings. The health-related literature on this issue was reviewed, by searching scientific articles in the medical Database PubMed and in the general database Web of Science as well as Nature database. In this literature review, 53 relevant peer reviewed articles on health effects of energy use and energy saving were found. Most of the studies had investigated residential buildings. One main conclusion from the review is that combined energy efficiency improvements in buildings can be associated with improvement of general health, such as less asthma, allergies, sick building syndrome (SBS) symptoms, respiratory symptoms, and reduced cold-related and heat-related mortality. Moreover, combined energy efficiency improvements can improve indoor air quality, increase productivity and satisfaction and reduce work leave and school absence. Effective heating of buildings can reduce respiratory symptoms and reduce work leave and school absence. However, some potential health problems can occur if increased energy efficiency will reduce ventilation flow. Energy saving by increasing air tightness or reducing ventilation is associated with impaired indoor air quality and negative health effects. In contrast, improved ventilation may reduce SBS, respiratory symptoms and increase indoor air quality. Installation of mechanical ventilation can solve the negative effects of making the building construction in dwellings more air tight. In future research, more studies are needed on health impacts of single energy efficiency improvement methods. Existing studies have mostly used a combination of improvement methods. In addition, modelling software programs should more often be used, since they can take into account effects of different energy efficiency improvement methods on indoor air quality in different types of buildings and in different climates.

Solar energy has come to the forefront as a scalable and largely underutilized renewable energy resource. The current cost of solar electricity, namely from photovoltaics, along with other logistics factors, has prevented the widespread adaptation of the technology. A key determinant of efficiency and cost for a solar cell is the current collector grid. This work presents the Collimated Aerosol Beam Direct Write (CAB-DW) system as a non-contact printing method that can achieve current collector grid finger widths of less than 10 μm which are amenable to decreasing both resistive and optical losses. The ability to produce high aspect ratio grid fingers, and deposit optimized grid structures on high efficiency SHJ solar cells using silver nanoparticle inks is also demonstrated. A decrease in shadowing and via profile modification of the grid fingers is presented, along with a study of aging and degradation of electrical properties within silver nanoparticle inks.

An exercise-induced energy deficit may affect post-exercise energy intake, physical activity energy expenditure (PAEE) and energy balance hormones. Therefore, the objective of this thesis was to investigate the impact of a single bout of exercise either of moderate (40% O2max) or high (70% O2max) intensity on post-exercise energy intake, physical activity energy expenditure and energy balance hormones in both sedentary and active males. Physical activity energy expenditure increased between 38 and 62 hours following moderate intensity exercise in sedentary males (Chapters 3 and 4). This was due to increased light intensity energy expenditure (2.4-4.79 METs) such as standing and walking activities (Chapter 4). The Change in PAEE was not associated with circulating leptin and adiponectin concentrations. There was no impact of a single bout of exercise on post-exercise energy intake in sedentary males during a buffet meal (Chapter 4). Chapter 5 aimed to determine whether changes in PAEE, energy intake, and energy balance hormones were related to physical activity status. Interestingly, plasma acylated ghrelin concentration was suppressed while total peptide YY (PYY) concentration tended to be elevated after high intensity exercise in active males (Chapter 5). However, there was no impact of either moderate or high intensity exercise on PAEE and post-exercise energy intake in active males. The final study (Chapter 6) determined whether high intensity exercise in the fed state after a few days of food restriction had an impact on circulating energy balance hormones. Circulating postprandial total PYY and pancreatic polypeptide (PP) were increased for one hour after high intensity exercise in active men. There was no change in PAEE and post-exercise energy intake after exercise.

"Large amounts of renewable energy generation are being introduced into modern power systems to decrease the environmental impact of power generation. Despite benefits, increased renewable energy penetration will likely create additional system instability and unpredictability. Increasing line capacity via redundancy of transmission networks and utilizing energy storage are two methods that can be used to increase transmission power system stability. This thesis investigates the economic effects of energy storage and line capacity in isolated test systems. Utilizing Powerworld Simulator, test systems based off two common industry test bed standards (WECC 9-bis, IEEE 14-bus) were built using scaled real-world generation and load data. Multiple Optimal Power Flow studies performed on the test systems with and without the addition of energy storage model revealed the incremental change in overall system cost of adding energy storage and highlighted the impact energy storage has on isolated systems with renewable energy."

"The photophysics of several bichromophoric dipeptide model compounds and two trichromophoric 15-residue peptides have been studied by a combination of absorption, fluorescence, phosphorescence and laser flash photolysis. Intramolecular singlet-singlet energy transfer (SSET) occurs efficiently within these systems. Trichromophore 14 undergoes intramolecular SSET from the central chromophore to the termini, kSSET = 5.8 x109 s-1 , with a five fold increase over 13, kSSET = 1.1 x 109 s-1 . Evaluation of SSET mechanisms via the Förster treatment and molecular modeling indicates that the dipole-induced dipole mechanism is sufficient to account for the observed SSET. However, given the close distances of the chromophores (~10 Å), an electron exchange mechanism can not be ruled out. Low-temperature phosphorescence in 1:1 methanol/ethanol and room-temperature laser flash photolysis in acetonitrile results indicate that intramolecular triplet-triplet energy transfer (TTET) is efficient in dipeptides 7,9-12 and proceeds with a rate constant of kTTET > 5 x 10 8 s-1. The occurrence of TTET in dipeptide 8, (biphenyl-naphthalene), could not be confirmed due to the fact that SSET from biphenyl to the naphthalene moiety was 26 times greater than kISC. Thus nearly all absorbed light was funneled directly the to the singlet manifold of the naphthalene moiety. TTET in the trichromophores could not be fully evaluated due to their low solubility. However, it is shown from 77°K experiments that kTTET is at least 2.2 x 102 and 2.6 x 102 s-1 for 13 and 14 respectively."

This thesis details potential design improvements by exploiting a new general grid model utilizing multiple wind and solar energy plants. A single renewable energy plant which relies on wind speed or solar insolation is unreliable because of the stochastic nature of weather patterns. To allow such a plant to match the requirements of a variable load some form of energy storage must be incorporated. To ensure a low loss of load expectation (LOLE) the size of this energy storage must be large to cope with the strong fluctuations in energy production. It is theorized that by using multiple renewable energy plants in separate areas of a region, the different weather conditions might approach a probabilistically independent relationship. The probability of energy generated from combined plants will then approach a Gaussian distribution by the central limit theorem. While maintaining the same LOLE as a single renewable plant this geographic separation model theoretically stabilizes the energy production and reduces the system variables: energy storage size, energy storage efficiency, and cumulative plant capacity. New generic weather models that incorporate levels of independence are created for wind speeds and solar insolations at different locations to support the geographic separation model. As the number of geographically separated plants increases and the weather approaches independence the system variables are reduced.