SEA’s energy engineers Jason Brooks and Archie Puckett sat in a loud chilled water plant one day at ADTRAN, hunched over their laptops. The two engineers were there trying to determine how they were going to optimize an already efficient chiller plant and prove their worth once again. Glaring intently at the Building Automation System (BAS) on their computer screens, they were thinking maybe, if they stared long enough, an answer may appear. They have done this many times before, always finding a nugget of energy savings gold, many times significant. They were nervously confident they could do it again, they had faith it would show itself. It was only a matter of digging in the right places. Searching for answers was their favorite part of the job!
SEA was tasked with evaluating ADTRAN’s East Tower chilled water plant. The owner wanted to improve the plant efficiency while continuing to provide consistent occupant comfort at a reduced energy cost. We sought to achieve this goal without ADTRAN incurring any additional costs through capital expenditures, such as new equipment or additions to existing equipment.
Jason had several ideas but none proved viable due to a trouble area within ADTRAN’s East Tower. This specific wing had challenges maintaining comfortable temperatures in the past and always presented problems. Any changes made to the chilled water plant would adversely affect this area, which is why ADTRAN was considering a capitol project to install an additional chiller for about $1,000,000.
As he studied the data for this particular area and the East Tower as a whole, Jason began to notice that other areas within the building had similar cooling requirements, but did not experience similar challenges in regards to meeting their cooling needs. This led Archie to conclude that the problem was not in the amount of cooling available, but in how that cooling was distributed. With that in mind, he adjusted the chilled water system main valves. Like magic, the problem area that had issues for more than a decade was solved. Except it was not magic that had solved the problem, it was SEA.
With this change made, another member of the SEA team, Eric Mobley, implemented programming modifications to the chilled water plant that generated savings of $71,000 a year. In addition, this solution provided an immediate cost avoidance of $1,000,000 that ADTRAN was planning on spending to install the additional chiller to meet the cooling requirements. More than 30 existing inefficient BAS programs were reprogrammed with new energy saving sequences. These included a new cooling tower fan staging sequence, a chilled water supply temperature reset, a new algorithm addressing the sequence and startup for the second and third chiller, new economizer sequences for existing Air Handler Units (AHUs) and economizer sequences for AHUs that did not have economizing capability prior, among others.
SEA will be presenting at ADTRAN’s Huntsville Campus February 21, 2019 for the North Alabama Chapter of ASHRAE. SEA team members will be joined by ADTRAN’s facility supervisor, Kelly Whalen. The presentation will serve as a walkthrough as Jason, Eric, and Kelley show attendees the facility, highlighting the work that went into optimizing the chilled water plant. Click here to learn more about the event.