The commissioning and testing phase of mission-critical electrical and mechanical systems project for a facility can be an opportunity to optimize the facility design in both cap-ex and op-ex. To realize these benefits, it is worth examining current approaches as well as a new, technique-based methodology and its supporting data.
by ComRent’s Director of Business Development and Technology Strategy, Mark Siira, and his IEEE partner, Alan Meissner.
This article, published in Consulting-Specifying Engineer, discusses some best practices for commissioning electric and thermal systems in a facility, such as a data center, in addition to introducing test data that suggests certain methods are more appropriate when optimizing the performance of a facility. These methods present an important new opportunity for engineers, contractors and commissioning agents, as proper testing and commissioning of data centers can lead to improved efficiency, and optimizing thermal performance of the facility. The need to test a facility, like any other complex system, is generally accepted and well supported for many reasons, including:
- Predictability of life
- Validate capital expenditure needs
- Lower operating expense
- Improved availability and reliability
Technique-Based Commissioning Testing
As the practice of commissioning mission-critical facilities has become more robust, a wide variety of approaches to commissioning the electric power system and power distribution, as well as HVAC within such a facility have emerged. Yet, there remains a vital need to engage in technique-based versus quantity-based commissioning and testing. A technique-based approach means that more precise simulation of the electrical performance and thermal performance of the equipment in the facility leads to an opportunity to optimize the facilities’ design for performance.
Through the work of ComRent and Engendren, providers of load banks and data center expansion solutions, respectively, a methodology for commissioning has been studied and suggested for mission-critical facilities. This new methodology supports a testing approach that permits optimizing versus oversizing facility designs and operations.
Data Center Containment Systems
For those unfamiliar with data center thermal management containment systems, the following paragraphs are meant to be a summary of the main approaches. This will form the basis for a discussion on testing practices.
In-Row Cooling Configuration
In-row cooling offers capacity and efficiency gains by moving the air conditioner from the perimeter of the room closer to the actual load. Installed in an array of industry-available options, in-row cooling arrangemenents provide local, focused cooling at the rows of server cabinets, which fill the data center. As implied, the cooling mechanism is generally situated between the equipment racks as they are arranged in single or multiple rows.
Overhead Cooling Configuration
Similarly, an overhead cooling arrangement, as implied, comprises a cooling mechanism situated over the racks and/or rack rows. Here again the strategy is to manage the heat loads at the source – an approach that is well published and proven to yield higher efficiencies.
Hot Aisle Containment Scheme
Most IT equipment flows cooling air from front to rear. The conventional approach is to align equipment racks in a side-to-side “row” arrangement – forming a physical separation between the cooler intake air on the fore side (cold aisle) and the warmer exhaust air on the aft side (hot aisle). Hot Aisle Containment entails capturing, containing and managing the “hot aisle” air before it migrates to other areas of the data center. This zone controlled thermal management strategy results in heightened HVAC system efficiencies and therefore reduced cap-ex and op-ex costs.