Improving Chiller Efficiency
Because an HVAC system is almost always the largest energy hog in a commercial or institutional facility, it is the most logical place to start when seeking to reduce energy waste. Chillers, in particular, can seriously deplete an energy budget when not operating at optimal efficiency.
Chiller oversizing is one of the largest causes of energy waste. Chiller systems are designed to run at peak efficiency when operating at or near full-load conditions. But, because full-load conditions occur only occasionally in a typical year, specific steps must be taken to optimize chiller operation to match existing load conditions. In facilities that have more than one central chiller, efficiency can be improved by staging operation. As the load increases, chillers are programmed to come online in stages and reduce energy use.
Installing variable-frequency drives on chiller motors is another good energy saving option. VFDs automatically alter motor operating speeds to match load requirements. Even at the lowest cooling loads, VFDs lower chiller motor speeds to allow them to run at peak efficiency, thereby reducing energy use, on average, by 30%.
Regular maintenance is important to ensure that chillers continue to operate at their maximum efficiency. Maintenance tasks should include leak testing, water-treatment to reduce scale, and annual cleaning of heat-transfer tubes.
PJM Mechanical Contractors, Inc. is a multi-faceted mechanical contractor providing construction and installation, service and maintenance, and design/build services in a comprehensive range of mechanical disciplines that include HVAC, plumbing, controls, refrigeration, custom metal fabrication, piping, fire protection, and backflow preventer testing. PJM primarily serves clients in pharmaceuticals, manufacturing, healthcare, institutional, and other various commercial and industrial sectors.