Operating budgets are steadily shrinking, while utility costs are progressively rising. District energy providers are feeling the squeeze — especially when a system is called upon to support continuing load growth and a major campus expansion. The University of Texas at Austin (UT) is tackling that challenge head on, with a strategic approach that not only increases its capacity but also the operational flexibility and efficiency of its heating, cooling and power generation systems.

The university’s Dell Medical School wants to establish itself as a leader in the modernization of academic medicine. Its new medical school district is the first in decades to be built from the ground up at a leading research university. The district includes a level 1 trauma center, which requires a high level of efficiency and reliability in its heating and cooling systems.

Using Load Growth as a Chance to Optimize

UT generates its own power through its efficient combined heat and power (CHP) system. With the increased load necessary to support the new medical district, the university’s Utilities & Energy Management group saw an opportunity to meet the need while simultaneously optimizing power, cooling and heating systems.

We worked with them to design and build facilities to support the expansion, with the goal of gaining substantial efficiencies with the overall system. The project included:

  • The 15,000-ton central chilling station 7 (CS7)
  • A field‐erected cooling tower
  • A 5.5 million-gallon per hour thermal energy storage tank (TES- 2)
  • A new hot water system that included boiler and heat pump chiller capacity within the CS7 plant
  • A satellite steam-fired hot water plant embedded within the medial district for fuel and geographic diversity

Designing a Texas-Sized TES Tank

The TES tank is worthy of the “everything is bigger in Texas” reputation. It’s designed to provide up to 13,000 tons of cooling for up to five hours, enabling the university to offset up to 6 MW of peak electrical load to the nighttime hours. Teamed with the existing thermal energy tank, the new system can shift up to 10 MW — enough peak load to offset the power demands of the new medical facilities while maintaining CHP system efficiency.

The new tank capacity successfully meets the project’s multifaceted goals by:

  • Enabling more control of the demand-side load, optimizing the CHP system and microgrid.
  • Offering flexible chilled-water capacity that can be deployed to cover any equipment outages.
  • Providing cost savings as a byproduct of increased efficiency.
  • Allowing a significant space addition while deferring expansion of the power generation system.

Meeting Big Goals with Smart Strategy

The project’s success relied on a proactive strategy, implemented using a flexible, problem-solving approach. Integrating a second tank into a closed chilled water system created interesting challenges for our design and commissioning teams, the constructor and UT’s operations staff.

We’re pulling back the curtain on lessons learned for a presentation at the upcoming IDEA Campus Energy Conference in Miami. I’ll be joined by Mike Manoucheri from UT on Feb. 22 from 12:15-12:45 p.m. to share some of our trials and victories from our time bringing this new system to life. I’d love to share our stories and learn more about the challenges your campus faces.

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Jeff Easton, PE, CEM, LEED AP, is a section manager in Burns & McDonnell’s OnSite Energy & Power Group. He focuses on campus-type projects including large-scale central chilled water plants, utility distribution, building-side HVAC design and overall campus design standards.