Lighting Control and Monitoring for Energy Efficiency: A Case Study Focused on the Interoperability of Building Management Systems

This paper presents some results of a project that has been aimed at developing an event-driven user-centric middleware for the monitoring and management of energy consumption in already existing public buildings. One of the strengths of the designed system is that it allows an easy integration of heterogeneous technologies and their hardware-independent interoperability. This is a feature of great importance for existing buildings, where already existing controls could be integrated with new technologies to enhance the energy efficiency of a building. The functionality of the system has been tested in a number of representative spaces of already existing public buildings, where the already installed HVAC and lighting services have been equipped with monitoring and actuating systems designed and implemented using commercial off-the-shelf wired and wireless devices. This paper focuses on the energy aspects, which have been obtained by applying the designed system to monitor and control the electric lighting fixtures of different office spaces. The outcomes obtained from the monitored data have shown some significant differences from the expected and previously estimated energy saving results, and this paper offers some possible explanations. Some criticalities, in part related to the characteristics of the commercial off-the-shelf adopted devices and in part to the difficulties encountered in monitoring and analyzing the huge number of recorded data, are outlined.

I. Introduction

Energy saving and the development of information and communication technologies (ICT) are two of the main goals of European policies in the field of Research and Innovation to mitigate climate changes by reducing emissions and to boost economic growth by accelerating the spread of innovative technological solutions [1], [2]. It is well known that the building sector is one of the main causes of the final global energy consumption: buildings consume nearly one-third of the final global energy and are responsible for about one-third of the total direct and indirect energy-related emissions [3]. Several policy instruments have been devised to limit building pressure on the energy sector since the 1990s. Building energy codes were initially only focused on new residential buildings, but then they have progressively been expanded to include new nonresidential buildings and, more recently, to cover existing buildings when they undergo renovations or alterations [4]–[6].