Open Access

Oscar Klier

• In view of expected rising demands for lighting around the world and in the European Union, efficient technologies for the generation of synthetic light help to mitigate resource consumption. Light-emitting diodes pose a promising technological approach to provide sustainable infrastructure for domestic-, industrial/commercial- and public lighting. This thesis discusses the potential of light-emitting diodes for sustained use in comparison to conventional lighting technologies. However, the achievement of this objective is challenging. A conventional concept of sustainability does not provide the right conceptualities in order to assess technological solutions and their technical implementations on grounds of their future viability. Therefore the concept of technological persistency is introduced as an adjusted strategy for assessment. It adapts the areas of activity, which constitute the three basic pillars of sustainable development to fit a technology-related, function-specificIn view of expected rising demands for lighting around the world and in the European Union, efficient technologies for the generation of synthetic light help to mitigate resource consumption. Light-emitting diodes pose a promising technological approach to provide sustainable infrastructure for domestic-, industrial/commercial- and public lighting. This thesis discusses the potential of light-emitting diodes for sustained use in comparison to conventional lighting technologies. However, the achievement of this objective is challenging. A conventional concept of sustainability does not provide the right conceptualities in order to assess technological solutions and their technical implementations on grounds of their future viability. Therefore the concept of technological persistency is introduced as an adjusted strategy for assessment. It adapts the areas of activity, which constitute the three basic pillars of sustainable development to fit a technology-related, function-specific context: environment, economy and society are modified in order to suit the requirements of assessing sustainability in lighting. Consequently the derived major subjects of technological persistency are consitiuted by the factors energy, materials and function. Subsequent assessment is conducted on the basis of a set of subordinate sub-factors of high topical relevance. The reconiciliation of technical specifications, resource strategic considerations and functional properties represents the main challenge in this approach. Hence a methodology of assessment is developed that takes thematic differences into account. By combining all assessment factors in a balanced and comprehensive analysis, the strenghts and weaknesses of the considered technological/technical solutions become evident. The assessed solutions comprise established conventional lighting technologies as points of reference and a selection of various LED-based lighting units designed for domestic, commercial and public applications. The results show that LED-based lighting systems represent favourable solutions with regard to the aim of energy conservation. By offering efficient transformation of energy into visible light and unparalleled durability they clearly surpass conventional light sources like incandescent lamps and gas discharge lamps. Also with regard to functional properties, solid-state lighting achieved gains and is now on par with previously prevailing lighting systems. Yet those advantages are accompanied by increased complexity. LED light sources represent intricate devices, which require the use of raw materials with unique properties and highly specialized functional materials. As production of LED illuminants is projected to increase in the near future, the availability of those materials might be uncertain. Regarding materials demand, the disassembly of the evaluated illuminants showed that resource usage is strongly dependent on technical implementation. Novel technical layouts and advances in LED fabrication therefore play an important role in providing more sustainable light sources for the future. In this way technological persistency of LED lighting can be further increased by enhanced efficiency, highly variable functionality and reduced consumption of materials.…