An automated method and system are provided for facilitating monitoring of energy usage within a data center. The method includes automatically determining energy usage of one or more electronics racks of a data center by automatically ascertaining time-based energy usage of the electronics racks. The automatically ascertaining includes obtaining multiple measurements of instantaneous energy usage by each of the electronics racks in the data center over a period of time, and then separately averaging the multiple measurements for each electronics rack to obtain the time-based energy usage of each electronics racks. The method also includes outputting the time-based energy usage of the electronic(s) racks to facilitate monitoring of the data center.