As the energy efficiency industry evolves, more complex efficiency projects, such as chilled-water system upgrades, are being implemented. This is due to both the completion of simpler efficiency projects at many sites and the large room for efficiency improvements in chilled-water systems that are custom designed for each application and site. Efficiency projects not only benefit the owner but also benefit the electrical grid and society as a whole. As such, electrical utilities see benefits in incentivizing and claiming these energy efficiency projects when customers are willing to go through the utility’s measurement and verification (M&V) process. M&V needs to be performed by a third party to determine the verified savings from a project. The verified savings are used by the electrical utility to provide a cash incentive to the customer and also to inform the owner about the actual economics of the project. M&V on a chilled-water system can get complicated and beresource intensive, depending on the adopted methodology.

This paper discusses several available methodologies andtheir limitations. A simplified methodology is then proposed,detailed, and applied to two case studies, one on a chilled-water plant serving space-cooling loads and another on achilled-water system serving industrial process loads. The simplified methodology allows the M&V evaluator to meter thesystem within a reduced amount of time, account for variationin system load, observe an improvement in system efficiency,and quantify the annual energy savings of the system. This results in a streamlined M&V process with reduced costs andimproved annual energy savings estimates, which leads tomore cost-effective utility efficiency programs that are beneficial to society as a whole.