|
|
Maintenance and engineering managers looking for streamlined operations and greater energy efficiency and savings in institutional and commercial facilities often turn to retrocommissioning. This process applies commissioning tactics to existing buildings to improve the way building components and systems function together.
What are the most important factors in deciding which systems to retrocommission?
NOLAN: We had several different criteria. A building had to be automated to be able to trend performance of the HVAC and other systems. We wanted systems that impacted the entire building and that were of value to the utility systems to reduce overall loading on the campus infrastructure. We wanted the core campus to be the focus because we have a cogeneration plant, and we wanted to be sure to get the best value we can out of having it onsite.
HOBBS: Cost-effectiveness, return on investment, energy savings, and operational efficiencies. In order for me to meet the comfort goals and quality goals that I had in mind, I had to have financial justification in mind. Return on investment was critical to getting the funding.
MAULDIN: We did a study and tracked and monitored almost a thousand different air-handler boxes in our (HVAC) system. We did that for approximately six-seven months. We looked at wasted air in spaces that weren't occupied.
How did you select the retrocommissioning team?
NOLAN: We took a multidisciplinary approach. We had the facilities management people that run the shops and do the repairs. We had to limit the number of buildings we would have liked to do at one time, based upon our staffing abilities. Obviously, the guys in the buildings are most knowledgeable of where we would get the value, and they provided a large amount of input to say this building would be preferred over another. The second choice was the building owners, the people who were going to use the buildings and know the buildings well. The university has a climate-action plan, and a goal is to reduce greenhouse gas emissions, so our office of environmental policy was involved. We had the utilities-management team who was responsible for the infrastructure of getting the utilities to the buildings.
HOBBS: In a sense, there weren't that many decisions I had to make. The city gas and electric needed to be part of the team for a few reasons. They are our utility, and they also were in a position to help me fund or justify the return of investment.
MAULDIN: Basically, our whole department (18 people) was part of the team. I headed the program up and handled most of the dealings from our side, plus I dealt with and worked closely with our retrocommissioning company. But everybody in our department had some hand in it.
How did you determine the scope of the project?
NOLAN: We took the input from the entire team, and we balanced it out to somewhat aggressive schedules. We were among the first to work with Connecticut Light and Power, and we decided to follow along with their rebate program. We narrowed down to the number of buildings we thought we could manage at any one time, and we figured it to about a million square feet at a time. Then after that, we checked to see if rebates were there to get financing.
HOBBS: I was the project developer, project manager, and project lead. It was my decisions about what we focused on, where we went; I put the packages together. I handled the budget development and administration of both payment and the activities that went into completing the work.
MAULDIN: I evaluated results and prioritized based on payback. Items that didn't show a payback or had a long payback were discarded. Out of a total of 12 recommendations, we did 11.
How much did cost factor into your decision to undertake the project?
NOLAN: Each energy-efficiency measure that we did, the payback goal (for each building) was to be less than three years, and it was OK to exceed that if the aggregate for the building remained less than three years.
HOBBS: Costs were huge. It was the hill I had to climb. The engineering survey cost $60,000, and if I had not been able to establish with ownership that there were mechanical deficiencies in the building that needed to be addressed, I probably would not have gotten the funding. Getting the (extra) $60,000 from an owner that had just developed a $220 million project [the hotel opened in the same year as the retrocommissioning project], was challenging. Because we were able to establish that there were outstanding issues that were in debate about whether they were a basic part of the scope of the original project or not, I was able to get support for it.
MAULDIN: It actually did play a major role in our decisions. Not that we were trying to save the most amount of money, but we were being careful with what our investments were and how we invested the money, to make sure that we did get the best return on our investment. We wanted to be as efficient as we could, and that was the main thing we looked at before we looked at the money.
What lessons did you learn from the retrocommissioning process?
NOLAN: Probably the No. 1 lesson would be to have more significant pre-planning meetings with people who would be performing the work. The pre-planning was crucial. Know the building, meet the owners, and make sure you're not going to impact any of the owner's schedules, and set a very definitive timeline for when you are going to commence the work.
HOBBS: Never give up, and work with great professionals. … Between what I was able to define to [the mechanical engineer] and direct him where to look, we were just able to win so many of the issues that the normal punch process failed to achieve for me. Communicate, communicate, communicate. Tell them what you're going to do, do it and tell them what you did. This particular project set the building up for a great first five years. The rebates we gained through the course of the year, they made the difference between a profit and a loss for the hotel. My general manager's eyes opened to that, and all of a sudden, the ownership team was seeing a great deal more value in these kinds of efforts than they ever did before. Saving dollars as a result of building this momentum early in the life of the building is significant.
MAULDIN: Listen to your building. Your building is telling you something every day, and if you don't recognize what it's saying you won't understand how to make it efficient. What we thought we had going and were right about, we found out there were much better ways out there.
How did you take advantage of the process's findings?
NOLAN: We got to use them as a training tool for some of the students on campus. ... A lot of templates we developed for measurement and verification we now utilize for other buildings. That gives us perhaps even a better idea as we go into the second, third and maybe future phases of retrocommissioning, of which buildings to target and where we can have the most effect to achieve our conservation goals.
HOBBS: During the first year, we were able to identify and get corrected about 24 of 28 major deficiencies. In addition to that, the effort resulted in 16 percent savings in electricity costs year over year and 25 percent savings in natural gas costs year over year. We're trying to set the culture from an engineering perspective that we'll manage this building for its life. Investing in inefficiencies and the quality of systems is important to establish early on in a building's life so that ownership has an awareness of its importance.
MAULDIN: Our investment totaled about $40,000, and we had that paid back within the first year. We took advantage of what was offered and ran with it and got a good return for it. That's not something that just stopped after the first year. We're continuing to benefit from that. Since we've done the HVAC part, we've gone on to do water and electricity.
Closer Look: Retrocommissioning |
