Many decisions are made during the design of a chilled water plant that have long-lasting impacts on the facility’s energy use and demand. Additionally, consistent operations, benchmarking, and submetering can help perpetuate savings throughout a building’s life cycle.
Chiller plants are commonly a building’s most costly upfront expense and often are one of the largest end uses of energy in a building. Given rising energy costs and demand prices, the impact of chiller plants on overall building performance and operations budgets has increased as well. Therefore, it’s important that chiller plants run efficiently to minimize the operational costs to the owner. Over time, the code requirements of ASHRAE 90.1, “Energy Standard for Buildings Except Low-Rise Residential Buildings,” for chillers have increased drastically, which is a great step in the industry’s move toward sustainability. For example, the full-load coefficient of performance (COP) of a 500-ton centrifugal machine has increased from 3.8 in the 1975 code to 6.28 in the 2016 code. Although technology has improved and manufacturers have achieved higher equipment efficiencies, efficient system design and operation continues to be important for the long-term efficiency of the building.