Colour Preferences and Energy Consumption in Retail Lighting Applications

National Technical University of Athens, School of Electrical and Computer Engineering, 15780 Athens, Greece

^* Corresponding author: andimitrakis@mail.ntua.gr

Abstract

Colour preference and energy efficiency have long been considered significant characteristics that cannot be maximized simultaneously. Numerous investigations on colour preference and evaluation have been carried out. Sources with larger gamut generally enhance object chroma, which has been found to be preferred by previous studies, however, excessively large gamut may lower preference due to oversaturation. This paper describes a psychophysical experiment for the comparison of the colour preference evaluation among sources of different hue-specific chroma changes and how preference affects energy efficiency. A retail lighting application was created in two side-by-side presentations. A two-metric colour rendering system, consisting of average fidelity and gamut metrics, cannot fully describe colour quality and underscore the importance of a colour rendering graphic. Different spectras with the same correlated colour temperature, average fidelity and average gamut were implemented using an optimized spectral power distributions calculation in order to have systematic variation in gamut shape. Participants of different ages made preference assessments of chromatic objects in a forced-choice protocol, where they evaluated the pairs in a sequential mode. Specific colours strongly influenced participants’ assessments, indicating that gamut shape, additionally to gamut area, is an important component of predicting colour preference and energy efficiency.