The use of 3D GIS to analyse the influence of urban context on buildings' solar energy potential

Buildings are responsible for 40% of energy consumption and 36% of Co, emissions in the European Union. To bring these levels down, governments are striving to promote a more efficient use of energy resources and an increase adoption of renewable energy technologies, as photovoltaic panels and solar collectors on the building envelopes. To fully exploit the potential of these technologies, a detailed analysis of the incident solar radiation on buildings roofs and facades is mandatory taking into account the geographical and urban environments. Three solar radiation tools, in association with two different modelling approaches (2.5D and 3D) handled by a 3D GIS tool, were applied to a city block of downtown Lisbon for both the winter and summer solstices and for different levels of detail of the surrounding context. The study showed that both built surroundings and topographic relief have an important impact on solar potential of buildings in urban areas. An average difference of about 30% in the results was observed between the simulations with and without the geographical and the urban environments included. The study also showed that the 3D approach has high potential to fully evaluate solar access in complex urban layouts, for accounting the irradiation of all sun-exposed surfaces of the buildings. (C) 2018 Elsevier B.V. All rights reserved.