Metering of energy used for lighting: a practical indirect method

Within large buildings, measurement of energy consumption is a crucial task. Rearely a separate measurement of the sole lighting component is available. Instead, estimating and or measuring the actual energy consumption due to indoor lighting only spent is an important goal since an accurate evaluation could help and guide energy managers and designers towards the most appropriate lighting system. Building automation and control systems (BACS) provide important data treatment procedures enabling such kind of monitoring. This paper analyzes some methodologies for calculating and measuring energy consumption for lighting systems, ranging from direct to indirect measurement techniques. This paper promotes a simple method for an indirect measure by adopting ordinary actuators and a basic supervisory system with a low cost impact.