A utility power outage during the summer of 2013 exposed several issues with Macy’s UPS infrastructure at their data center. With the holiday shopping season approaching, Macy’s assembled a team consisting of our PTA staff, a general contractor, an electrical contractor and a UPS vendor to address these issues. The team replaced two existing Liebert NX Series 330 kVA solid state UPS systems (circa 1994) with two new Eaton Powerware 9395 550 kVA UPS modules in a fast-track design-build manner without interruption of power to the existing data center loads. All of the work was completed and commissioned prior to the start of Macy’s holiday data center “blackout period”. With the Phase 1, 2N redundant, UPS replacement successfully completed, Macy’s authorized the team to develop a multi-year Tier III redundant design to accommodate their100 kW annual IT load growth rate and identify required upgrades to the utility power, standby generator power, UPS power, electrical distribution and mechanical cooling systems. A 30-year master plan and construction drawings, consisting of Phases 2 through 7, were released in the summer of 2015.