Why did you choose North Carolina as the site of your data center?
Gary Simpson: One of the larger reasons was to have close proximity to the IT organization. Our product engineering is in [Research Triangle Park]. We have our IT presence and large engineering presence here, and that was important to us. .
Mark Skiff: From an operating standpoint, the economizer is really the key. The chiller can account for over 50% of annual energy use. What we've done is configure the air handling system to bring in outside air. . Does that work well in North Carolina, which is a pretty warm climate?
M.S.: The hottest days in Raleigh still get down to the 70s at night, so we're able to do free cooling then. We're on full or partial free cooling 98% of the time, and on full free cooling 75% of the time. . We also change the supply temperature throughout the day. It's 70 to 75 degrees (Fahrenheit) during occupied periods and 80 degrees during unoccupied periods. What we do is monitor the hot-aisle occupancy with the building management system. It's smart enough to know that if no one is in the hot aisle, it can ramp up the temperature. That then allows us to have a chilled-water system that is not your typical 42-degree water system. We make it 55 degrees, … so it will run about 25% better. . What else?
M.S.: We control the volume of supply air in the cold aisle based on static pressure, and we exactly match the airflow required in the rack equipment by the supplier system. Most air-handling systems deliver about 30% more air than needed. That's a big savings. . Let us know what you think about the story; email Mark Fontecchio, News Writer. Also, check out our blogs: Data Center Facilities Pro, Mainframe Propeller Head, and Server Farming.