Case Study

Retro-commissioning of Three (3) Marriott Hotels, PG&E Territory

Enovity recently completed building retro-commissioning at three Bay Area Marriott Hotels. The retro-commissioning work was partly subsidized by the $7.2 Million 2004-2005 CPUC Statewide Building Tune-up Program and project construction implementation was contracted to Enovity directly by the Marriott Corp. The three hotels included the Downtown San Francisco (Moscone Center) Hotel, the 2nd Street Hotel and the Marriott Hotel at the San Francisco Airport in South San Francisco. With a heavy focus on building automation systems (BAS) technology, we helped the Marriott optimize their energy systems while facilitating incentives for the installation of measures that improved building operations, comfort and energy efficiency.

Activities included scoping audits, equipment assessments, pre-functional checks and spot measurements, sensor calibration checks, monitoring plan development, point trending and stand-alone data logging, review of BAS programming, functional testing, and detailed energy calculations. Enovity provided construction management for selected sites and self-performed measure implementation at the two San Francisco hotels. Project deliverables included a scoping audit report with measure energy savings estimates and project cost, a retro-commissioning plan, a monitoring plan, and project implementation reports. Total combined measures savings for all three Marriott’s were $326,700 annually, with 2,668,400 kWh in electricity savings, and natural gas savings of 61,800 therms. Total project cost is approximately $458,700, resulting in an overall payback of less than 2 years. Measures for sites include: