Urban Acceptability of Building Integrated Solar Systems: LESO-QSV Approach
Abstract
The concern for sustainable development issues together with the new EU promotion policies are finally leading to a widespread use of Photovoltaic and Solar Thermal systems in buildings. This upcoming reality is opening a new debate on the urban/architectural acceptability of such systems. In Switzerland the matter has been regulated from 2008 by the art.18-a/LAT, stating that all “carefully integrated” solar systems not attempting to the cultural or natural heritage are accepted. But this text remains ambiguous, and is differently interpreted by solar pros, building heritage administrators and city planners, actually leading to unfair decisions . The detailed evaluation of each of these characteristics in relation to the whole building design leads to a comprehensive and objective quality evaluation, summarized in a “grade” after carefully balancing the impact of each aspect. Finally a table of acceptability conditions is established on the basis of three variable local factors: - Urban context sensitivity (the quality of the architectural environment); - System visibility (close and remote visibility of the proposed system); - Socio-political context (political and energetic priorities specific to place and time).