Case study: How one facility cut utility costs by 59%

Note: This article is the first in a series of case studies of buildings that we managed in Columbus, IN that had been designed by world-class architects. Read the introductory article here.

Background

The Quinco Consulting Center was first occupied in the fall of 1972. By 1980, mostly as the result of rapidly escalating energy costs during the “Oil Embargo” of the mid-'70s, the utility costs had risen to the point that they were taking needed funds away from the primary mission of the facility.

As my first project after founding Holmes AutoPilot LLC in 1979, we were hired by the owner of the facility to help reduce utility costs. Our contract called for us to operate and maintain the energy systems on an incentive basis. Our only fees were a percentage of documented utility savings each month. We were on call 24/7 and it was our job to maintain comfort as we were making changes to reduce the utility costs.

The problems

Problem 1: The architect had designed a building where maintaining comfort would be nearly impossible.

The building had won several awards for architectural design. Built like a bridge, it spanned the creek below it. From a thermal standpoint, however, spanning the creek meant that all sides of the building were exposed to the elements: not only the walls, windows, and roof, but the underside also. The building was long and narrow, 200 ft x 50 ft, with 30,000 square feet on three floors.

The long north and south walls were mostly glass and were oriented east to west. There were more than 7,000 square feet of single-pane windows in aluminum frames mounted on uninsulated concrete walls. Half of the windows were on the north side, and half were on the south.

Problem 2: In their attempt to overwhelm the thermal deficiencies of the building, the HVAC engineers designed a system much more complex than needed.

It called for three air handling units to supply 55 degree air year around. Each room had a thermostat controlling a hot water coil in the ductwork supplying that room. Although this was a fairly standard design at the time for larger buildings, it was totally inappropriate for this building, which was long and narrow, with all exterior rooms on both sides of a center hall. All rooms needed heating in the winter and cooling in the summer. There was no reason for the chillers to run in the winter or the heat to run in the summer. The main air handlers could provide 100% fresh air in the spring and fall for cooling.

Problem 3: There was no way a single perimeter loop could serve both the sunny and shady sides successfully; further, an installation error caused the single thermostat to operate incorrectly.

Unknown to us, the occupants had experienced terrible comfort problems from the first day the building had opened. As soon as we started working there we discovered the night staff wearing winter coats in the middle of the summer. They froze in the winter and burned up when the sun hit the south windows in both summer and winter. Half of the building was an in-patient facility; people needing help lived in those conditions 24 hours a day.

A single loop of hot water radiators ran completely around the perimeter of the building, both first and second stories, under all of the windows, facing both north and south. There was one thermostat in one room on the south side of the building that controlled the perimeter heating loop.When the drywall had been installed during the building construction, a workman had accidently pinched the black pneumatic tubing closed that ran to that thermostat. This resulted in the perimeter heat going into “full heat”, its fail safe or freeze protection mode.

It had been running full out since the building was built, 24 hours a day, 365 days a year, summer and winter for nearly 10 years. This resulted in the air conditioning system running 24/7, 365 days a year to attempt to remove the excess heat. The heating and cooling systems were fighting each other to try to maintain comfort.

How could this problem have been missed by everyone associated with the mechanical system during that time? I wish I knew. But by spending enough time in the building and being responsible for both comfort and energy costs, we found the problem using basic problem-solving techniques. Nearly 40 years later, I clearly remember tracing the tubing above the ceiling, down the wall and finding and fixing the problem.

The solution

All the building really needed was a way to modulate the heating in the winter and cooling in the summer for just a few zones: the first and second floors, north and south sides, the in-patient wing that was occupied 24/7, and the office wing that was used 8 AM – 8 PM, M-F.

What did we do? The first thing was to start spending as much time in the building as possible to identify problems and manually change the operation of the energy systems to match the actual needs of the building and occupants. The second was to design, build and install our very first energy monitoring system so I could monitor the comfort and operation of all the energy systems 24/7.

Changes included:

  • Shutting down multiple blowers, pumps, chillers and boilers when not needed.
  • Shutting off the office wing on nights and weekends.
  • Using outdoor air for free cooling whenever possible.
  • After discovering that improper chemical treatment had cracked multiple sections in the two cast iron boilers, they were replaced with multiple high efficiency hot water boilers. Piping and valves were designed to separate space heating from domestic water heating.
  • Separating the single-zone perimeter heating system into six loops, each controlled by a zone thermostat.

As a result of these changes, annual utility costs were reduced by 59%.

The Case Study was presented at the 1983 Institute on Energy and Engineering Education at Ohio State and published in Vol. 80, No.6, 1983 Journal of the Association of Energy Engineers. The project received a Special Energy Conservation Award from the Governor of Indiana.

Read more about this project in my articles:
Rube Goldberg Winner – Early Temperature Control Systems

Remote and condition monitoring offer tremendous “avoided costs” potential but often hard to justify

One final note. One of first times I was working in one of the treatment rooms, I clearly heard a woman describing some very intimate problems. I looked around to see if she was sitting behind me but found she was in the next office.

We discovered that interior walls that separated the counseling rooms as well as the bedrooms had not been properly soundproofed. There were gaps between the partition walls and the exterior window-walls. Plus the single perimeter heating pipe that ran the full length of the building penetrated every one of those partition walls and seemed to amplify the sound.

Unbelievable for a mental health facility. It may have looked good to the judges handing out the architectural awards but in my opinion, it had completely failed to achieve its primary purpose - to provide a comfortable space for treatment of people with mental health needs.