IDCA’s innovative “chiller-less” design concept for Stanford University’s new research computing facility capitalizes on the San Francisco Bay area’s temperate climate to meet the thermal challenge posed by high-density server racks operating 24X7/365.
The use of computational fluid dynamics (CFD) to analyze airflow and temperature patterns was a key to the design, which brings in outside air at the lower level of the two-story building to cool the basement electrical support equipment before rising through open floor grating into cold aisles on the second level. The cool air is pulled into the servers and exits into dedicated hot aisles which are vented through roof-top louvers.
In this way, the waste heat is continuously removed from the building rather than being mechanically cooled. With an average local outside air temperature of between 55 and 65 degrees Fahrenheit (between 13 and 18 degrees Celsius), only a few days exceed the high or low temperatures required for optimal computer performance, making the location ideal for a sustainable, low-energy facility.
When the outside temperature exceeds the limit for natural cooling, supplemental cooling water from existing cooling towers will be used in lieu of chillers. In the winter, a portion of the hot exhaust air will be recirculated and humidified to keep the temperature and humidity in the range required for server operations. Drought tolerant landscaping will capture stormwater for irrigation, while south-facing rooftop louvers will provide optimal placement for solar panels.
Calculations for the preliminary design concept indicate an 85 percent reduction in the facility’s carbon footprint, a 75 percent reduction in estimated mechanical energy cost, and a 20 percent reduction in total energy cost.
Program requirements include the server room and support spaces for utilities, shipping and receiving, and a central utility plant. Situated on a gradual 30-foot slope, the facility occupies minimum site area. The two-story design organizes support equipment on the lower level and the server space on the upper level.
IDCA’s multi-phased approach achieves modularity and flexibility, and allows the University to expand its data center capacity as needs and budgets allow. The total computing facility will be constructed in four phases, with each phase including two modules. Eight modules are anticipated at full build-out. Computing and building systems are targeted to achieve the Uptime Institute Tier III level of redundancy.
The result is an energy efficient, high-density data center with secure and reliable capacity to meet the immediate and long term needs of the University, at the lowest cost.