Feature
Story
Making Efficiency Pay:
UT Austin upgrades
chiller plant, controls
Jim Hanna, Cofounder and Chief Technology Officer, Optimum Energy LLC;
Long before many jumped on the growing green marketing trend, universities and colleges across
the country began adopting their own
energy efficiency initiatives – often out
of sheer necessity. The potential for
energy savings on campuses is high
for a variety of reasons, as most are
open 24 hours a day year-round and
require reliable energy solutions to
meet varying equipment and occupancy
needs. With the added impetus of
outside pressures – including state
mandates requiring green building
certification or the ‘call for green’ from
students, faculty and staff – energy
efficiency initiatives simply make
sense. Energy efficiency strategies
allow campuses to provide campus
facility occupants with the same levels
of service and comfort they currently
enjoy, while lowering operating
expenses, simply using less energy.
Whether the requirement for energy
efficiency is driven by complying with
mandates, competing for students and
staff, or reducing operating costs, uni-
versities and colleges across the country
face a common challenge: funding. Energy
efficiency initiatives can pay for them-
selves, however. The University of Texas
at Austin (UT Austin) serves as a prime
example of this. In the past few years, a
chiller plant upgrade and new demand-
based plant control software have enabled
UT Austin to optimize its district cooling
system – reducing energy use even as
campus cooling needs have grown.
Meeting the Challenge
A large urban campus, UT Austin
utilizes more than 17 million sq ft of
space in 150 buildings serving 70,000
students, faculty and staff – requiring
a variable and uninterrupted supply
of energy. In fact, UT Austin’s district
cooling system has had a reliability of
99.9998 percent over the past 35 years.
Since 1928, UT Austin has been
energy-independent, connecting to the
Texas electrical grid only for emergency
backup. The campus is served by a
combined heat and power district cooling
system that provides 137 MW of on-site
power generation; 1. 2 million lb/hr of
steam generation for plant use and
distribution for campus space heating
and domestic hot water; 45,000 tons
of chilled-water cooling capacity; and
a 4 million-gal chilled-water thermal
energy storage system. Since UT Austin
self-produces all the energy for the
campus from natural gas, it acts as a
utility provider and charges the various
on-campus users for the energy it
supplies (i.e., auxiliary clients such as
athletics, student recreation, dining and
housing, as well as campus classrooms,
and research and administrative facilities).
In a relatively short span of 12 years
(1996 to 2008), the UT Austin campus
grew by 20 percent – approximately
4 million sq ft of building space.
Accommodating this growth and managing operating costs proved to be a
challenge. Cooling needs in particular
played an important role, because the
production of chilled water consumed
approximately one-third of the energy
produced by the CHP plant.
“My challenge in any major capital
project is to be revenue-neutral, and
budget-neutral, with a payback that creates equal or positive cash flow from
