Enhanced Re-commissioning is the process of reviewing existing equipment and systems to meet these same objectives, and it can be a highly effective way to meet facility performance goals by reducing operation and maintenance costs and cutting energy consumption.
It is observed that re-commissioning achieves energy savings in the range of 6-15%, with potential payback periods of less than two years. Many buildings realize even greater cost savings and quicker paybacks. Re-commissioning also achieves other important outcomes, such as improved indoor comfort and air quality, lower operation and maintenance costs, greater occupant satisfaction, extended equipment lifetime, safety benefits, and better overall operating performance.
A detailed re-commissioning plan involves following steps:
- Assessment of original design and current operations. A re-commissioning project will begin with the assembling of all available information from the original building and systems design and commissioning, including plans, specifications, drawings, and equipment manuals.
- A complete survey of the building systems’ conditions and operations. The initial assessment also involves analysis of the building’s current operational needs. Depending on the facility’s size and complexity, this may take weeks to several months to complete.
- Gap analysis. Once design intent and current conditions are assessed, the commissioning engineer conducts a gap analysis to identify problems, inefficiencies, and potential improvements. The results of the evaluation are compared to the original design intent of the building and the current demands. The project might identify an array of issues, ranging from high utility costs, energy inefficiency, and occupant complaints to system failures and health and safety risks.
- Prioritize actions. The commissioning engineer then work with the facility manager to prioritize the issues, conduct a cost analysis, and decide on which improvements to make. Recommendations might include small adjustments that can achieve significant savings or retrofitting projects. Investment decisions are based on the best and most cost-effective ways to reach the objectives.
- Train staff. Re-commissioning often provides rapid payback, but long-term savings require staff training in order to uphold the benefits of systems improvements. A preventive or predictive maintenance program should be put in place to ensure the best results for many years to come.
- Implement continuous commissioning. Once the systems have been re-commissioned, facility need to sustain the benefits through an ongoing process of reviewing the operation of systems and equipment to assure that they continue to operate at maximum efficiency.