Plastic photovoltaic roof tiles

[摘要] ENGLISH ABSTRACT: This project investigated the feasibility of incorporating photovoltaic cells intoplastic roof tiles using injection moulding. Such tiles have the potential to providerobust and distributed electricity contained within the building envelope.Current-voltage curves of amorphous silicon modules were measured underillumination using the PVPM 2540C power measuring instrument, both beforeand after moulding. The efficiency after moulding was reduced by 53% to 88%,with modules that were heated for longer being degraded more. Thus theduration of exposure to high temperatures affected the extent of performancereduction during moulding. This suggested that faster moulding at a lowertemperature or faster cooling could solve the problem.Economic feasibility was examined by calculating the levellised cost of electricityprovided by the tiles. A large-scale development in the Western Cape wassimulated using a typical meteorological year of weather data and using theanisotropic diffuse irradiance model of Perez et al. (1988). Avoided costs dueto replaced roofing, avoided costs due to electricity distribution infrastructure,and Clean Development Mechanism credits were accounted for. The cost ofenergy calculated was R11/kWh in 2010 rands, which did not compete withthe price of conventional grid-based electricity at R1.8/kWh. The importanceof the cost of balance-of-system components, such as the inverter, and not onlyof the photovoltaic modules, was highlighted for future cost reductions.Several clear guidelines for manufacturing photovoltaic roof tiles were discovered.The most important of these was that many bypass diodes make thesystem more robust.

[发布机构] Stellenbosch University