Integrating a Data Center into an Engineering Laboratory Building
Sean Convery, P.E., Cator, Ruma & Associates, Co.
The Engineering 2 Building at Colorado State University (CSU) is a facility spanning 120,000 square feet, housing high-tech engineering laboratories consisting of wet laboratories, electronic laboratories, offices, and classrooms. In addition, a data center with 2,000 square feet of space is included. The data center will be a hybrid of low-density racks consolidated from other parts of campus mixed with high-density racks to be installed in the future.
With the laboratory air system requiring 100 percent outside air, the data center provides a perfect opportunity to truly recover energy. By having the data center in the penthouse adjacent to the outside air intake louvers, hot air can be relieved out of the data center back into the main outside air intake and then taken down to the air handling units (AHUs) in the basement to be used for primary heating of the rest of the building. This hot air recovery comes from the low density racks that are capable of being cooled with conventional overhead air conditioning. With the expected 85 to 95 degree air coming from the hot aisles, heat can be recovered for the building any time the outside air temperature is less than 50 degrees, which is 50 percent of the year in this area of the country. When the temperatures are above 50 degrees, the warm air is simply relieved out of the building while all of the AHUs remain in outside air economizer mode. It should be noted that CSU does not require its data centers to be humidified, which allows for additional energy savings to be witnessed by not wasting humidified air.
For the high-density racks (greater than 12 kilowatts) a water cooled in-row system must be utilized. In-row cooling must be accomplished with higher chilled water temperatures to avoid condensation from forming on the cooling coils. Because the building is served from campus chilled water, which operates more efficiently with a higher "delta-T," the best method of energy performance is to use the chilled water twice by using the return chilled water from the AHUs in the building. By using the chilled water twice, the delta-T on the chilled water system for the building could be in the 15 to 20 degree range versus the typical 12 to 15 degree range. This application can also be used for other process cooling systems, such as chilled water used for chilled beam systems.
Sean T. Convery joined Cator, Ruma & Associates, Co., a mechanical/electrical engineering consulting firm of 93 persons, in 1995, and is a principal in its Mechanical Department. Mr. Convery has a Bachelor of Science in mechanical engineering and is a professional engineer in Colorado. Mr. Convery has a broad array of experience in the design of mechanical systems focusing on higher education campuses and research laboratories. Recent laboratories include the Colorado State University (CSU) Research Innovation Center (LEED® Gold), CSU Engineering 2 Building (LEED Gold Pending), University of Colorado (CU) Boulder System's Biotechnology Building (LEED Platinum Pending), and CU Denver Anschutz Medical Campus Research Complex energy efficiency upgrades. Mr. Convery was a presenter at the past two Labs21 Annual Conferences and has received Engineering Excellence Awards from the American Council of Engineering Companies in Colorado for his designs at complex biosafety level 3 campuses.