Revisiting cooling energy requirements of residential buildings in Portugal in light of climate change

Since climate data for building energy simulation have recently been refreshed with 1971-2000 observational data and theoretically influenced by a conservative approach of climate change, benchmarks for cooling energy requirements for residential buildings are discussed for a set of 30 regions in Portugal, mainland and islands, as a contribution to the next revision of Portuguese building thermal code (DL 118/2013). The main conclusion is that gain utilization factor correlates with average external air temperature for summer season by a logarithmic function. The benchmark for gain utilization factor plays an important role in defining cooling energy requirements. A set of recommendations are suggested: (i) using the gain utilization factor as an index to evaluate the overheating risk, thus, for values above a defined threshold cooling energy needs could be neglected for primary energy demand quantification; this measure may encourage designers to integrate passive cooling systems; (ii) defining a national roadmap based on technological advances of shading solutions for benchmark parameterization of the west equivalent collecting area by unit of floor area starting from 0.065. (C) 2014 Elsevier B.V. All rights reserved.