Achieving energy efficient data centers using cooling path management coupled with ASHRAE standards

Power trends for data center facilities continue to grow at an alarming rate. In response to this, data center operators are now implementing various practices such as adding blanking plates, hot aisle/cold aisle containment, etc. Also, in response to ASHRAE´s expanded thermal guidelines [1], many data center operators are now raising the supply air temperature in an effort to further conserve energy. However, airflow in a high-density thermal environment is a complex phenomenon and requires an appropriate engineering analysis to understand all of the factors. Improperly implementing such practices, which are now known as “Industry Standard Practices”, may result in overheating of IT equipment and thus negatively affect data center operations. In the following scenarios, Cooling Path Management (CPM) is used to understand the airflow / thermal environment of the facility. ASHRAE thermal guidelines are then followed to increase the average temperature of the room. In later scenarios it is shown that with proper airflow management, ASHRAE recommendations can be implemented using a full engineering analysis. Results from the final scenario show that the CRAH unit set point can be increased by 23.8°F from the baseline scenario and 5.5 kW of stranded capacity can be regained. Results also show that “Industry Standard Practices” only enable the CRAH unit set point to be increased by 13.4°F. Following the CPM method and ASHRAE thermal guidelines will enable operators to make tangible changes to their data center using objective data.