The impact of key parameters on the energy requirements for artificial lighting in Italian buildings based on standard EN 15193-1:2017

Lighting represents 15%–20% of the world's electricity consumption in the building sector. Therefore, copious guidelines are available to reduce the impact of CO2 emissions produced by the construction sector. In line with this, the UNI EN 15193-1:2017 provides three methods to calculate the Lighting Energy Numeric Indicator (LENI), which quantifies the annual electricity consumption for lighting per square meters. Literature shows an extensive knowledge concerning lighting analysis of offices and educational buildings, since those categories require both high levels of comfort and energy consumption. However, the recent growth of the lighting sector led the designers to include residential, commercial, and industrial cases as well. In this framework, this study aims to develop nine-building typologies, reported in the standard, and to calculate their lighting energy needs using the LENICALC software, a new user-friendly program. Moreover, a set of architectural and lighting system parameters were analyzed and combined to investigate their influence on the overall LENI of the nine buildings. Based on those results, the reachable energy-saving targets of the cases were drafted, grouped in a preliminary lighting benchmark, to provide the reader a broader view of the influence of these factors on lighting consumptions.