NetBem : business equipment energy monitoring through network auditing

Modern office buildings are fully equipped and furnished spaces with arrangements including networked business equipment, such as PC-class machines, copiers, wireless routers and fax machines, and other electrical equipment such as home appliances e.g. coffee machines, and appliances for environmental comfort e.g. electric heaters. The unique characteristics of networked business equipment are well-defined usage pattern, low-power current draw, and connectivity to the local area network (LAN). Business equipment is generally used over working hours adding up to important costs, motivating the need for a system capable of tracking equipment usage and associated energy expenditure, as well as identifying cost saving opportunities. Techniques for monitoring power loads are generally based on power step edge detection, and cannot be applied to business equipment due to the low power consumption of individual devices. This paper presents NetBem, a novel energy monitoring technique ad hoc to office buildings, capturing the contribution of networked business equipment to a power load via side-band detection of the equipment’s operating state through the LAN. The technique is presented, and results from experiments within the School of Computer Science and Informatics at University College Dublin in Ireland are given.