Here are some handy stats on power consumption in data centers Data Center Energy Summit taking place at Sun Microsystems today. Casually drop these factoids at your next cocktail party. Less than nine months: that the time it takes to recover the cost (in terms of lower electrical bills) for putting variable speed fans in a server rather than a fan that runs at a constant, high rate, according to Mukesh Kattar, energy director at Oracle. He tested it and thought payback would take 16 months, The fans, though, only had to operate at 55 percent of their regular speed on average, he said. 1 to 1.8. That's the ratio of power dedicated to support (air conditioning and cooling) compared to the power dedicated to actually running the server when you install these kinds of fans, Kattar added. In a regular situation, the ratio is 8 to 10. He's aiming for a 1 to 3 ratio. 80 degrees Fahrenheit. That's the temperature of the intake air servers can tolerate, according to Dean Nelson, who runs global lab and data center design services for Sun. Sun conducted a chill-off with several different cooling systems. Most servers are sold to work in environments with 65 degree intake air. (Intake air is the air that gets sucked in by fans to cool down the servers.). "So why are we cooling at 65," he asked. $19 billion. That's the total value of datacenter construction projects being undertaken by 21 large customers in the U.S. at the moment, according to Nelson. Data center construction is probably the only healthy segment of the building industry. A million bucks. That's what a raised floor costs in a good-sized data center, according to Nelson. Historically, raised floors were used to store the cables that connect computers as well as the cold air blowers. With new cooling techniques, you don't need these anymore. 50,000 square feet and 5 megawatts. That's the size and power consumption of a large data center today, according to Subodh Bapat, who runs Sun's energy efforts 500,000 square feet and 50 megawatts. That's the average large datacenter in 2020, he said. 8,500 hours. That's the number of hours in a year that you could cool your data center in San Francisco with ambient air. There are only 8,760 hours you have to worry about. $18.5 billion. The amount of money spent on data center power in 2005, according to Bapat. $250 billion. The amount of power spent on data center power if nothing is changed in 2012, according to numbers touted by Bapat from IDC. Gar.