Energy Efficiency on Chilled Water Systems

Chilled water systems are often the preferred option of cooling for large commercial and industrial buildings. In large HVAC systems as used in airports and campuses, water serves as secondary refrigerant and transports heat from the air handler units (AHU) to the chillers (the chilled water loop), and then through another piping system (the condenser water loop) from the chiller to the cooling towers, if water-cooled chillers were applied.

These water systems include pumps, piping, valves, and heat exchangers which are better optimized as a group than individually. Within this complex network lie many opportunities for improving energy efficiency, comfort, and maintainability. This dynamic system, which provides cooling for many air conditioning applications, is one of the most energy intensive systems in commercial buildings, so understanding how the different components of a hydronic system interact is essential for designing an energy-efficient and cost-effective chilled water plant.

This section examines efficiency opportunities for water-side cooling systems and components. The energy efficiency approach to chilled water systems was divided into two categories: Cooling water and Distributing Water. Energy saving potential applying modern variable flow control schemes will be covered in Distributing Water. Cooling Water will be focused on controlling chillers in variable flow systems and measures to face the low delta-T syndrome in chilled water plants.