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This dissertation explores the texture of women's lives in an urban informal area, with the particular aim of highlighting their use of domestic energies in the absence of their access to electricity. The investigation into domestic fuel usage is situated within the context of other basic needs: shelter, water and food and the acquisition of these. Each is separately explored. The domestic fuel sources used by the women were primarily paraffin and candles. The dissertation argues that there is no simple equation between household income and fuel purchase but that the acquisition of food and fuel are mutually dependent and contingent upon a complex set of variables which include the perceived physical and emotional well-being of the woman and her household. Furthermore the dissertation argues that given the extent of informal settlements and poverty nationally, candles and paraffin are likely to continue to be extensively used in the future. despite their disadvantages and the desirability of electricity. The dissertation submits that the reasons for this pertain to the accessibility and relative affordability of paraffin to households whose buying power is constrained as much by the form in which their income is derived as by its inadequacy. These arguments are elucidated through case studies of ten women who live in non-electrified homes in Canaan. The women concerned monitored their consumption of and expenditure on water, food, and fuel for a month, and met once a week as a group while they were doing so. Finally the dissertation suggests that national energy planners should take into account the manner in which women perceive and manage their housekeeping roles, particularly cooking, as well as the form in which household income is derived in order to determine strategies and energy policies which would would be women-friendly and support the needs of the extensive numbers of impoverished households in South Africa. / Thesis (M.A.)-University of Natal, Durban, 1992.

This work presents a new wireless Visible Light Communication lighting system targeted to future Smart Buildings. A digitally controlled LLC resonant dc-dc converter targeted to white LED luminaires is demonstrated. Visible Light Communication is implemented with minimal incremental cost, by operating the LLC converter in burst mode, without causing any visible disturbance. The converter operates with a regulated average LED current by adjusting the switching frequency, while the burst pulse timing is controlled to minimize the current disturbance and minimize the value of the output capacitor. Variable Pulse Position Modulation is used to modulate the data, while supporting a range of dimming settings. A digital demodulation scheme that supports variable frequency transmission is demonstrated. The 80 W, 400 V to 23 V converter experimental prototype has a peak efficiency of 93.8 %. The bit error rate of the complete system is fully characterized versus distance and angle.

Daylighting, a form of illumination utilizing sunlight, has been used by architects as a method of symbolic expression in religious architecture. Light can be used to illustrate architectural comcepts or to satisfy the liturgical requirements of the particular religious denomination. This thesis illustrates some of the techniques employed by well-known architects, critiquing their successes and failures, and weighting them against more conventional works designed by lesser-known architects in order to discover what separates the ordinary from the extraordinary.The city of Columbus was chosen for its outstanding reputation of producing well known works of architecture, or "icons." Five churches have been singled out on the basis of their exemplary use of daylighting:First Christian ChurchNorth Christian Church First Baptist ChurchSt. Peter's Lutheran ChurchSandy Hook United Methodist ChurchResearch undertaken involved studying the philosophies of each architect, critically assessing the theories of light in earlier historical periods, and defining how some of these earlier concepts have influenced today's architects, if at all. By closely adhering to these principles, the architectural and spiritual value of the church increased greatly. / Department of Architecture

The thesis is aimed at the investigation of niche applications of solid-state lighting with controllable colour-rendition, spatial, photochemical, and photobiological properties. In order to employ the controllability of light emitting diode (LED) based lighting technology, the research on such niche applications as artwork illumination and street lighting are focussed. The smart colour rendition engine (CRE), which allows for continuously tuning metameric spectra with different colour rendition properties, is introduced. The results on the subjective validation of the statistical colour rendition metric using the CRE are presented. The main requirements for artwork illumination are overviewed and the application of the intelligently controlled CRE in artwork illumination is investigated in two aspects: a) the establishment of subjective needs in colour quality of illumination as a function of the contents of artworks and the observers’ cultural background and b) the effect of the control of photochemical damage irradiance on the visual impression from artworks, while adjusting the chromaticity and colour rendition properties of the illuminant. The results on the optimization of the luminance distribution within an intelligent lighting installation for pedestrian areas using the identification of subjective impressions are presented. The low-circadian action LED source for outdoor lighting is introduced and the results on the assessment of photometric, colorimetric... [to full text] / Ši disertacija yra skirta ištirti kietakūnio apšvietimo su valdomomis spalvų perteikimo, erdvinėmis, fotocheminėmis ir fotobiologinėmis savybėmis galimus nišinius taikymus. Kaip nišinių taikymų pavyzdžiai, kuriuose ryškiausiai atsiskleidžia valdomo apšvietimo privalumai, buvo pasirinkti dailės kūrinių apšvietimas ir gatvių apšvietimas. Šiame darbe pristatytas išmanusis spalvų perteikimo variklis (SPV), leidžiantis tolydžiai keisti metamerinius spektrinės galios skirstinius, pasižyminčius skirtingomis spalvų perteikimo savybėmis. Naudojant SPV validuotas statistinis apšvietimo spalvinės kokybės vertinimo metodas. Apžvelgti dailės kūrinių apšvietimo reikalavimai bei pristatomi SPV pritaikymo dailės kūrinių apšvietimui pagal du kriterijus tyrimai: a) įvertinant apšvietimo spalvinei kokybei teikiamos subjektyvios pirmenybės priklausomybę nuo dailės kūrinio turinio ir žiūrovų kultūrinės kilmės; b) parodant regimosios išraiškos pokytį, atsirandantį dėl apšvietos lygio kitimo, kuomet fiksuojama apšvietimo fotocheminė įtaka apšviečiantiems paviršiams, kintant kokybiniams apšvietimo parametrams. Pristatomi apšvietimo skirstinio pėsčiųjų zonai optimizavimo rezultatai, gauti įvertinus subjektyvius poreikius. Pasiūlytas žemo cirkadinio poveikio kietakūnis šviesos šaltinis, skirtas lauko apšvietimui. Įvertintos tokio šaltinio fotometrinės, kolorimetrinės, spalvų perteikimo, fotobiologinės ir šviesinės taršos savybės bei atlikti tyrimai, įvertinantys psichofizines savybes.

Ši disertacija yra skirta ištirti kietakūnio apšvietimo su valdomomis spalvų perteikimo, erdvinėmis, fotocheminėmis ir fotobiologinėmis savybėmis galimus nišinius taikymus. Kaip nišinių taikymų pavyzdžiai, kuriuose ryškiausiai atsiskleidžia valdomo apšvietimo privalumai, buvo pasirinkti dailės kūrinių apšvietimas ir gatvių apšvietimas. Šiame darbe pristatytas išmanusis spalvų perteikimo variklis (SPV), leidžiantis tolydžiai keisti metamerinius spektrinės galios skirstinius, pasižyminčius skirtingomis spalvų perteikimo savybėmis. Naudojant SPV validuotas statistinis apšvietimo spalvinės kokybės vertinimo metodas. Apžvelgti dailės kūrinių apšvietimo reikalavimai bei pristatomi SPV pritaikymo dailės kūrinių apšvietimui pagal du kriterijus tyrimai: a) įvertinant apšvietimo spalvinei kokybei teikiamos subjektyvios pirmenybės priklausomybę nuo dailės kūrinio turinio ir žiūrovų kultūrinės kilmės; b) parodant regimosios išraiškos pokytį, atsirandantį dėl apšvietos lygio kitimo, kuomet fiksuojama apšvietimo fotocheminė įtaka apšviečiantiems paviršiams, kintant kokybiniams apšvietimo parametrams. Pristatomi apšvietimo skirstinio pėsčiųjų zonai optimizavimo rezultatai, gauti įvertinus subjektyvius poreikius. Pasiūlytas žemo cirkadinio poveikio kietakūnis šviesos šaltinis, skirtas lauko apšvietimui. Įvertintos tokio šaltinio fotometrinės, kolorimetrinės, spalvų perteikimo, fotobiologinės ir šviesinės taršos savybės bei atlikti tyrimai, įvertinantys psichofizines savybes. / The thesis is aimed at the investigation of niche applications of solid-state lighting with controllable colour-rendition, spatial, photochemical, and photobiological properties. In order to employ the controllability of light emitting diode (LED) based lighting technology, the research on such niche applications as artwork illumination and street lighting are focussed. The smart colour rendition engine (CRE), which allows for continuously tuning metameric spectra with different colour rendition properties, is introduced. The results on the subjective validation of the statistical colour rendition metric using the CRE are presented. The main requirements for artwork illumination are overviewed and the application of the intelligently controlled CRE in artwork illumination is investigated in two aspects: a) the establishment of subjective needs in colour quality of illumination as a function of the contents of artworks and the observers’ cultural background and b) the effect of the control of photochemical damage irradiance on the visual impression from artworks, while adjusting the chromaticity and colour rendition properties of the illuminant. The results on the optimization of the luminance distribution within an intelligent lighting installation for pedestrian areas using the identification of subjective impressions are presented. The low-circadian action LED source for outdoor lighting is introduced and the results on the assessment of photometric, colorimetric... [to full text]

East Timor is rebuilding its stock of infrastructure after decades of underdevelopment and a wave of violent destruction in 1999. As part of this process the Government of East Timor aims to improve access to electricity from less than five percent of the population today to eighty percent by 2020. An important strategy to meeting this aim will be the use of solar home systems (SHS) in remote rural locations. To develop its policy for the deployment of SHS, the Government of East Timor must decide what size of SHS is optimal. This research investigates whether there is a relationship between SHS size and development. / The research adapts an evaluation approach developed by World Bank/UNDP Energy Sector Management Assistance Program. This approach uses a combination of participatory and quantitative tools tailored to the East Timorese context through consultations with rural households about electrification and their use of SHS. Three SHS projects in East Timor were selected for evaluation, each of which had adopted a different sized SHS for their program. The smallest systems installed were 10 Wp single-lamp systems. The largest system was rated at 80 Wp and was supplied with four or six lamps. The third type of system was 40 Wp and provided three lamps / To assess the development impact of these different sizes of SHS, a set of Participatory Evaluation exercises were conducted with seventy-seven small groups of SHS users in twenty four rural communities. These exercises were supplemented with a Socio-economic Household Survey of 195 SHS users. The combined results of these evaluation processes enabled the three sizes of SHS to be compared for two types of benefits—assistance with carrying out important household tasks (i.e. ‘lighting-derived’ benefits) and attributes of SHS which were advantageous in comparison to use of non-electric lighting sources (i.e. ‘intrinsic’ benefits). Analysis of the research results showed that the small 10 Wp SHS provided much of the development impact of the larger systems. For lighting-derived benefits, there was little difference between the development impact of small and large systems. The larger systems provided greater benefit for domestic tasks undertaken in kitchen buildings, since the small and medium sized SHS did not provide lighting in these areas. For intrinsic benefits related to health and convenience, the small systems provided much the same benefits as larger systems. For financial benefits—considered by East Timorese SHS users to be the most important of the intrinsic benefits—smaller systems were found to offer slightly positive benefits due to their lower operating costs. Larger systems, however, were found to have a negative overall financial impact. / The research suggests three significant implications for the design of SHS programs in East Timor and comparable situations elsewhere: programs should focus on providing smaller systems rather than larger ones; systems should be designed to provide a light in the kitchen wherever possible to maximise the overall development impact; and SHS operating costs should be carefully matched to the incomes of rural householders to ensure that operation of the systems can be sustained by user households.

East Timor is rebuilding its stock of infrastructure after decades of underdevelopment and a wave of violent destruction in 1999. As part of this process the Government of East Timor aims to improve access to electricity from less than five percent of the population today to eighty percent by 2020. An important strategy to meeting this aim will be the use of solar home systems (SHS) in remote rural locations. To develop its policy for the deployment of SHS, the Government of East Timor must decide what size of SHS is optimal. This research investigates whether there is a relationship between SHS size and development. / The research adapts an evaluation approach developed by World Bank/UNDP Energy Sector Management Assistance Program. This approach uses a combination of participatory and quantitative tools tailored to the East Timorese context through consultations with rural households about electrification and their use of SHS. Three SHS projects in East Timor were selected for evaluation, each of which had adopted a different sized SHS for their program. The smallest systems installed were 10 Wp single-lamp systems. The largest system was rated at 80 Wp and was supplied with four or six lamps. The third type of system was 40 Wp and provided three lamps / To assess the development impact of these different sizes of SHS, a set of Participatory Evaluation exercises were conducted with seventy-seven small groups of SHS users in twenty four rural communities. These exercises were supplemented with a Socio-economic Household Survey of 195 SHS users. The combined results of these evaluation processes enabled the three sizes of SHS to be compared for two types of benefits—assistance with carrying out important household tasks (i.e. ‘lighting-derived’ benefits) and attributes of SHS which were advantageous in comparison to use of non-electric lighting sources (i.e. ‘intrinsic’ benefits). Analysis of the research results showed that the small 10 Wp SHS provided much of the development impact of the larger systems. For lighting-derived benefits, there was little difference between the development impact of small and large systems. The larger systems provided greater benefit for domestic tasks undertaken in kitchen buildings, since the small and medium sized SHS did not provide lighting in these areas. For intrinsic benefits related to health and convenience, the small systems provided much the same benefits as larger systems. For financial benefits—considered by East Timorese SHS users to be the most important of the intrinsic benefits—smaller systems were found to offer slightly positive benefits due to their lower operating costs. Larger systems, however, were found to have a negative overall financial impact. / The research suggests three significant implications for the design of SHS programs in East Timor and comparable situations elsewhere: programs should focus on providing smaller systems rather than larger ones; systems should be designed to provide a light in the kitchen wherever possible to maximise the overall development impact; and SHS operating costs should be carefully matched to the incomes of rural householders to ensure that operation of the systems can be sustained by user households.

Far from being simply a necessary appliance to extend our day, artificial light has a great influence on human behaviour and wellbeing, perception of the surroundings and comfort. The energy needed for lighting is also a significant impact on our natural resources. For these two broad reasons lighting systems that improve the human visual and perceptual experience and reduce energy use are of widespread value. This work covers research into the application of LED technology as the next generation of mainstream lighting. It looks at the reasons why this technology is set to become the dominant way in which we light our lives, and the technical hurdles that are slowing this shift in lighting. It also presents the development, testing and prototyping of such an LED lighting product for use in the architectural market. This niche application is where LED lighting is currently most suited, due to the compactness, colour adjustability and lower colour rendering required. Establishing the technology here will help to gain consumer appreciation and acceptance of this beneficial and useful new paradigm in lighting. The design incorporates a shape that is pleasing to the eye with a simple oval profile. It was designed to be subtle and compact, blending into the ceiling as cleanly as possible. Practical testing on the finished prototype showed it to produce a wide range of colours and colour temperatures, while maintaining a safe LED temperature. The simplicity also makes the unit competitive in terms of cost.