Once managers determine a facility could benefit from retrocommissioning, they must determine the scope of the process — whether to focus on one key system or tackle the entire facility.
“If they complete the Energy Star analysis and the facility (score) is under 60, it’s more than likely to be more than one system,” Newman says. “For instance, if the boilers and chillers in a facility were replaced 30 years ago, it’s pretty obvious, even without a real energy audit, that managers need to look at them. They’re pretty close to the end of their useful life.”
The scope of the process also might depend on assessing the range of changes that have been made to the facility.
“Maybe a system received a change in occupancy,” Flatley says. “One of the most common ones is converting a cafeteria space to an office space. What work was done to accomplish that? What systems now serve that area, and are they the same systems as before? That’s a key to system retrocommissioning. Maybe a given floor or set of floors were fitted out and they had new systems installed that interface with the main system (and) that could benefit from a system-type commissioning. It’s really a budget issue — how much can they afford?”
Managers with a good understanding of the daily inspection, testing and maintenance that front-line technicians perform also should have a leg up on determining the scope of retrocommissioning.
“There’s a pretty good chance that the maintenance costs are going up every year,” Newman says. “This is what managers really need to look at — the trend on maintenance costs, whether it’s rooftop units that might last only 15 or 20 years or a centrifugal chiller that can last well over 25 years. And today’s boilers and chillers are so much more efficient than those of 25 or 30 years ago. That would be a target audit, which doesn’t cost as much as a full-building audit.”
Retrocommissioning: Getting Back to Efficiency
Retrocommissioning: Finding Barriers to Energy Efficiency
Setting the Scope for a Retrocommissioning Project
How to Ensure a Successful Retrocommissioning Project