Evaluation of Urban Compactness Indicators and Solar Potential in the Urban Environment

Abstract

One viable solution for clean onsite energy production and utilisation is Building Integrated Photovoltaics (BIPV). The available area for installation may not be sufficient to meet the building energy demand in high-rise urban buildings in tropical climates, although rooftops are ideal for photovoltaic (PV) module integration. This causes a requirement for the utilisation of facades. Furthermore, the unplanned urbanisation in Colombo has resulted in a difficulty in quantifying urban compactness and solar potential in urban environments. Therefore, there exists a requirement to assess the applicability of urban compactness indicators in quantifying solar irradiation on building envelopes in the urban contexts. This paper attempts to evaluate the credibility of several urban compactness indicators in relation to solar potential and establish the most applicable indicators in regard to the context of Colombo. The results showed that the roof to envelope area ratio provides optimum accuracy for predicting solar potential in the urban context of Colombo, Sri Lanka, whilst the average heights ratio exhibited the lowest. These results are significant for urban planners and developers when considering urban design guidelines.