Lighting Quality and Energy Efficiency in Public Buildings: a Comparative Evaluation of Retrofit Solutions

Abstract

In the world context, the consumption of electric energy has been one of the concerns related to sustainability in several constructive typologies. According to the IEA (2019), almost 15% of the world's electricity consumption is for lighting, representing 5% of annual greenhouse gas production. In Brazil, energy consumption in residential and commercial buildings, services and public buildings in Brazil, corresponds to 42.6% of the total electricity consumed in the country (EPE, 2019), with lighting accounting for approximately 22% of this total in commercial buildings (PROCEL, 2006). In view of the efficient requirements, daylight quality has a fundamental role in improving environmental conditions and, in this sense, methods and tools for assessing the quality of lighting have emerged, such as those recommended by IEA SHC Task 50 (IEA, 2016). The present article evaluates the retrofit of lighting in similar public buildings that presented significant differences between lighting projects and applications of the retrofit of lighting. The methodology included real-time monitoring of buildings in non-residential buildings, covering four aspects: energy use, retrofit costs, quality of the light environment (photometry) and user evaluation (GENTILE et al, 2016). The PBE Edifica labeling method is used to check lighting quality attributes and retrofit costs. There is real monitoring in the buildings and interviews with users. As results, there was a large cost difference between the two case studies, but it is shown that obtaining A-tag is not always a result of illumination quality.