Category: Primary/secondary

tekWorx Empowers JCI Client to Slash Operating Costs 68%

bayfront1-resized-600

BAYFRONT AT A GLANCE

  • 480-bed private hospital
  • 75,000 ft2
  • Over 3,000 employees
  • (4) York chillers
  • 2,575 tons installed cooling capacity

APPROACH

  • Convert plant to Integrated Primary/Secondary® design
  • Reconfigure tertiary pumps to alleviate system pressure problems and eliminate wasted energy
  • Add VFDs to all building pumps to eliminate wasted pump energy
  • Design and install PLC based adaptive control algorithms to ensure maximum chiller loading, optimal control of all CHW pumps and proper balance of cooling towers and chillers

IMPLEMENTATION

  • CEO ® system connected directly to JCI Metasys system via BACnet IP protocol, allowing tekWorx to gather real-time data on temperatures, flows, etc., and to fully control all plant equipment
  • Failover sequence developed and implemented to address control redundancy
  • No plant downtime during the course of this project
  • All major equipment remained in operation during commissioning

RESULTS

  • Manually operated system operating at 1.1kW/ton is now a real-time adaptive control system operating at .75 kW/ton
  • System experiences much less wear and tear
  • Operators are now freed up to perform other important tasks
  • CEO® User Interface has provides the staff with better insight into the system for diagnostics and trouble shooting

To learn more about this study and to see how tekWorx can help to optimize your plant, visit www.tekWorx.us

Issues with Primary and Secondary Chiller Plants

plumber fail-resized-600

An energy efficient design is the last thing on a property owners’ mind during the construction of a chilled water plant. Typically, the chief concern revolves around keeping construction costs to a minimum, ignoring future utility costs and energy efficiency considerations that are critical once a building is fully functioning. Due to this altered focus, chiller systems have historically been built using the classically inefficient “primary/secondary” (P/S). This configuration simply makes sure the building doesn’t run out of cooling on the hottest day of the year and gives no consideration to the expense of this strategy.

With respect to energy, one of the greatest causes for concern with these P/S systems is what is known as blending. Blending occurs as the chilled water combines with warmer water, thereby decreasing the temperature of the return water into the chiller. Because the chillers outputs are spec’d based on a designated temperature set point, energy is being wasted as the system fights to maintain its set point with the influx of warmer water.

To combat this issue, tekWorx has developed an “Integrated Primary/Secondary” retrofit design (IPS®) that brings valuable primary energy benefits to existing primary/secondary systems. Depending upon the specifications of a system, the IPS® substantially improves flow and reduces blending. The IPS® requires minor mechanical/piping changes and control system modifications, keeping the overarching facility infrastructure intact with minimal interruption to the current cooling operations. To see how tekWorx IPS™ can improve your ∆ T, fill out our Chiller Plant Evaluation Form.