Retro-commissioning (RCx) is the application of the commissioning process to existing buildings. RCx identifies low-cost operational and maintenance improvements in existing buildings and/or systems and brings them up to the design intentions and optimal performance of their current usage. Depending on the age of the building, RCx may resolve problems that occurred during design or construction, or address problems that have developed during the building’s life.
If you’re wondering whether your facility may be a good candidate for RCx, the chances are highly probable that system improvements could be made. Many existing facilities never have been commissioned, and equipment aging, changes in usage/occupancy and degradation in various components (including control calibration) require retuning on a regular basis.
Unless a building has been recently commissioned (or has a proactive, monitoring-based commissioning program, most facilities are good candidates for RCx. Even well-constructed buildings experience performance degradation over time, leading to inefficient operation, wasting energy and compromising reliable performance.
The return on investment for RCx projects is typically very attractive, with cost savings providing a payback on the study and implementation investment within two years or less. Depending upon the identified energy conservation measures (ECMs), utility and operating costs may be reduced once the recommendations from the RCx report have been completed: electric (demand and consumption), gas, operation and maintenance (O&M) costs and equipment replacement.
Additional benefits should be:
• improved system operation
• improved equipment performance
• increased O&M staff knowledge
• increased asset value
• improved occupant comfort
• improved indoor air quality
• improved building documentation/information
Depending upon the opportunities identified, cost savings associated with an RCx effort can range between 5 percent and 30 percent of the building’s operating costs. Simple payback of the capital investment is often between 0.4 to 2.4 years.
All forms of building commissioning share the same goals: to produce a building that meets the unique needs of its owner and occupants, operates as efficiently as possible, provides a safe, comfortable work environment and is operated and maintained by a well-trained staff. RCx also will help increase your staff’s knowledge of your facility and how to operate its systems more efficiently.
For additional information or to determine if your facility is a good candidate for retro-commissioning, please contact Jean Dussault at jdussault@hanson-inc.com or Bob Knoedler at rknoedler@hanson-inc.com.