Resiliency is a number one priority for any business. For data centers, it’s importance is monumental. Internet demands make data center failures disastrous to the data center owner and their clients. Retro-commissioning (RCx) is a key strategy in avoiding disaster and improving resiliency. RCx, the commissioning (Cx) of existing systems, can be challenging in data centers because of complex mechanical and electrical systems and the integration of advanced monitoring and controls the systems.
Phases of Data Center RCx
There are four phases to data center RCx; planning, investigating, implementing, and handoff. (Keep in mind that during these phases, the data center must remain online.) The commissioning agent gathers data from key personnel to identify objectives and risks. The owner’s project requirements (OPR) are reviewed for any significant changes that may have occurred from their inception. Feasibility of RCx is assessed at this stage as well. If equipment is at the end of life or an equipment change is desired, RCx is not a good course of action.
With the data and objectives gathered, the Cx agent creates a retro-commissioning plan that includes many factors such as weather, availability of systems, and the departments affected. When retro-commissioning is a colocation data center, the Cx agent must review the service level agreements (SLAs) and take care not to unintentionally violate them. The Cx agent then discusses the plan with stakeholders, weighing risk and financial impact.
The second phase is an investigation involving a study of the building, systems, and operating procedures and manuals. Safety plans are developed. Results from past functional performance testing (FPT) and integrated systems testing (IST) are reviewed, and a testing plan is further developed. Scheduling the RCx work is done in collaboration with operations managers to develop a beset overall strategy that keeps departments running during the process. The RCx plan is shared with appropriate management and ownership.
Once the RCx plan has approval, the Cx agent is ready to perform the approved scope of work. This is considered the implementation phase. As RCx activities commence, key metrics such as power usage effectiveness (PUE), water usage effectiveness (WUE), and energy usage are tracked. The Cx agent also identifies measures that are reviewed and tracked during ongoing commissioning.
Lastly, the Cx agent creates a final RCx report. Final versions of the standard operating procedures for dealing with critical situations are detailed. System set points and key metric values are outlined. Any changes made to systems are documented. The Cx agent submits the report to building stakeholders and operators, which can be presented in an informative meeting with the Cx agent outlining the data and procedures required to keep the data center’s performance at the optimum.
Benefits of RCx
For data centers, the improvement of reliability and lowered risk that RCx provides is enough of a motivating factor to reach out to a commissioning provider. But there are further benefits to engaging a Cx agent for an upcoming project, compliance requirements, or to improve operations. RCx provides a thorough and systematic check of all operating equipment, identifying operational and maintenance improvements that enhance system performance. And a major benefit of RCx is the energy savings that can be achieved.
The Savannah River Site (SRS) Data Center performed RCx with the goal of improving energy efficiency. The project was successful and showed that basic adjustments to existing systems can result in significant energy savings without significant investments. SRS engaged a Cx agent to perform the four phases of RCx as described above. By making the following adjustments the equipment as determined by the commissioning agent during functional testing, SRS achieved notable savings.
- Eliminated electric reheat
- Turned off humidification devices
- Tuned floor tile airflow
- Turned off three CRAC units
The estimated cost or RCx was $25,000, which may seem steep until you learn that the estimated savings are 1,400,000 kWh in a year, a simple payback period of two and a half months. Note these are only a few of the measures implemented or recommended during the RCx process.
We need our data centers to be reliable, not that society is so reliant on the internet. Retrocommissiining is a practical exercise with measurable results. This service should be an easy sell to ownership and easy to achieve by partnering with experienced and smart solutions providers like Albireo Energy.
