Case Study
Balancing Act: Maximizing Cold Storage Capacity While Minimizing Energy Use

A leading pharmaceutical company in the Northeastern United States implemented tekWorx Xpress® optimization system in January 2022. The 400,000 sq. ft. research and production facility had recently expanded its cold storage capacity from 30,000 to 50,000 sq. ft. to meet increased vaccine production demands.

Challenge

The 66% expansion in cold storage capacity threatened to significantly increase energy costs. The facility needed to ensure their 4,500-ton chiller plant could efficiently manage the additional cooling load without proportionally increasing energy consumption and operational costs.

Xpress® Optimization System in Action

The Xpress® system was integrated with the facility’s existing building automation system (BAS) and began optimizing the chiller plant operations on Day One, directly impacting cold storage efficiency. Key improvements included:

  1. Chiller Efficiency Enhancements:
    • Xpress® adaptive algorithms continuously adjust chiller operation based on real-time cold storage demands
    • Efficiency curves for all chillers showed significant improvement, effectively managing the increased demand from expanded cold storage
  2. Chilled Water Distribution:
    • The conversion to a variable primary flow system allows for more efficient distribution of chilled water to cold storage areas
    • This reduced pumping energy while ensuring stable temperatures, directly offsetting the increased demand from the expanded cold storage
    • Primary pumps and cold storage distribution pumps operated at optimized speeds, reducing pumping energy while ensuring stable temperatures in cold storage areas
  3. Load Management:
    • Xpress® effectively manages load changes from cold storage door openings and product movements

Results

tekWorx holistic optimization approach allowed the facility to absorb the increased cold storage demand without significantly increasing overall energy use. The implementation of the Xpress® optimization platform led to impressive results:

  • Despite a 25% increase in overall cooling load due to cold storage expansion, total chiller plant energy consumption increased by only 5%
  • The facility avoided $560,000 in projected additional energy costs associated with the cold storage expansion
  • Overall chiller plant efficiency improved from 0.85 kW/ton to 0.68 kW/ton, a 20% enhancement
  • Temperature fluctuations in cold storage areas were reduced by 35%, ensuring better product stability and quality control