The Energy Optimizer-Data Center Edition (AREO-DC) from Arch Rock Corp., San Francisco, CA, is a wireless monitoring system to provide continually updated information on a data center's electrical usage and thermal status. The system uses the company's PhyNet IP-based wireless sensor network, deploying wireless sensors to measure electrical, thermal, flow, and pressure conditions on power circuits, server racks, computer-room air-conditioners or air handlers, chillers, and below raised computer-room floors. Data are transmitted to a graphical multiwindow dashboard. The system enables data center managers to baseline the data center against ASHRAE benchmarks; identify factors causing energy waste; optimize available capacity for new servers based on actual electrical/cooling consumption of equipment.