Technical College in Indiana – Retro-Commissioning (RCx)

This higher education institution serves more than 200,000 students annually across Indiana. Michaels Energy partnered with the College’s facility management via Duke Energy’s Retro-Commissioning (RCx) program to perform a Find-and-Fix study at one campus, including four buildings served by chillers, boilers, and multiple AHUs and VAV systems.

Challenge

As campus schedules evolved over time, HVAC operation hadn’t kept up with occupancy. All four buildings were scheduled for occupancy almost 18 hours a day, six days a week, even though actual occupancy was lower. Trend data showed some air handling units in two of the campus’ buildings were running 24/7, ignoring schedules and maintaining occupied setpoints day and night. Temperatures were comfortable, but the campus was paying for it with narrow deadbands, minimal setbacks, and no optimal start strategy on most AHUs. The economizer logic was also leaving savings on the table by relying on simple dry-bulb lockouts rather than comparing outdoor air to return air conditions.

Solution

Through Duke Energy’s RCx Find-and-Fix program, Michaels Energy helped the College:

• Right-size HVAC schedules so each building operates in occupied mode only when students and staff are present, with Saturdays now added only as needed and new holiday schedules in Buildings 1 and 2.
• Broaden temperature deadbands in all four buildings and reset unoccupied setpoints to 60°F heating / 80–82°F cooling, reducing after-hours conditioning while maintaining comfort.
• Enable optimal start on all AHUs in Buildings 1 and 2 so systems start just early enough to meet morning setpoints instead of running hours ahead of occupancy.
• Upgrade economizer control to a comparative enthalpy sequence on Buildings 1 and 2, using both outdoor and return air conditions to decide when “free cooling” makes sense, and raising Building 3’s economizer lockout to 65°F.

Results

Implemented measures deliver verified annual savings of about $21,000, 172,000 kWh, and 5,750 therms, cutting energy use intensity by 5.3 kBtu/ft². The study also identified future opportunities, including extending optimal start and schedule fixes to Buildings 3 and 4 and adding chilled water and pump differential pressure resets, giving the College a roadmap for deeper savings as the campus continues to modernize.