||LOCATION: Helena, Montana (state capitol)
MARKET SECTOR: Computer Farm/Data Center
FACILITY SIZE: 15,024 square feet
CAPACITY: Up to 13 rows of racks or 247 cabinets
FACILITY PEAK LOAD: 1.0 megawatt (MW)
EQUIPMENT: Heat Wheel, Kyoto Wheel System
FUEL: Heat from electronic equipment
USE OF THERMAL ENERGY: Heating/Cooling Data Center and Transportation Maintenance Building
WHR TOTAL EFFICIENCY: 85 percent of conventional
ENVIRONMENTAL BENEFITS: Leadership in Energy and Environmental Design (LEEDS) certified
TOTAL PROJECT COST: $7.2 million
YEARLY ENERGY SAVINGS: $919,900 (at cap)
PAYBACK: 7.26 years
IN OPERATION SINCE: August 2010
The SMDC in Helena was the first data facility in the United States designed and built from the ground up using an old technology with a new twist: the Kyoto wheel, built by Kyoto Cooling, Inc. Rotary heat exchangers, or heat wheels, have been used for a long time for industrial air conditioning systems, but not as a ventilation solution for data centers. Total Site Solutions designed the SMDC with a state‐of‐the‐art primary cooling system by Kyoto Cooling. The design is specific to data centers and emphasizes energy savings. The only power required is for the fans that move large volumes of air and a motor used to rotate the heat transfer wheels that absorb the hot air of the data center equipment.
The SMDC was designed with waste heat recovery (WHR):
- to avoid mixing hot and cold air;
- to use as much outside cooling air as possible;
- to better control system temperatures and reliability;
- to increase efficiency and to reduce energy costs; and
- to increase system redundancy.
The rotary heat exchange system alone is sufficient 86 percent of the time, supplemented by computer room air conditioning (CRAC) units 10 percent of the time. The CRAC units operate solely only 4 percent of the time.
The SMDC also has a 99 percent efficient uninterruptable power supply (UPS) system that provides nine minutes of battery backup at 100 percent load. Two 1,000 kw diesel generators are also capable of providing backup power over extended periods of time. At the moment of utility power loss, the backup systems engage, balance the load, and synchronize until supply transfers back to the utility. A heat pump and air handlers heat and cool the staffed facility with an external glycol loop assisting the heating of a neighboring transportation maintenance facility.
This data center’s cooling system is 85 percent more efficient than a conventional data center. A conventional data center has a typical power usage efficiency (PUE) ratio of 2, where one part is from the cooling load, and the other is from the IT load. The SDMC PUE is 1.15, where the lower cooling load at SMDC represents “0.15”--an 85 percent savings compared to a conventional data center using computer room air conditioning (CRAC) units.
In addition, Montana’s transition from conventional servers to the SMDC has saved additional load and costs. The conventional load for the Department of Administration in Helena was 340 kw, but went to 58 kw when transferred to the SMDC—a cost savings of $247,032 annually just from the reduced information technology equipment load. With those additional savings, the payback on the SMDC is 7.26 years when at capacity.
In addition to reduced cooling costs, the SMDC is able to use more efficient computer equipment as it becomes available. For example, the uninterrupted power supply at the SMDC is 99 percent efficient, an improvement of over 18 percent of the past supplies. The current IT load is about 147 kw, and will grow as more state agencies move servers to the facility.