The Green Grid has published a Fresh Air Cooling Map showing the best places in the United States to use outside air to cool data centers. This practice - also known as free cooling or air-side economization - allows data center operators to save money by using fresh air to cool server rooms, rather than relying upon chillers that use large amounts of energy. Free cooling typically requires filtering for particulates and careful monitoring of humidity in the data center. Geography matters, as the temperature and humidity conditions will determine how many hours a year a data center can use free cooling.
The Green Grid, an industry consortium promoting more energy efficient data center operation, has created a color-coded heat map illustrating the regions offering the highest annual hours of free cooling. A low-resolution version is pictured above. Access to a high-resolution version is limited to Green Grid members.
The group has also published a free cooling tool that allows users to create a customized analysis of the potential for a particular zip code, and allows users to set their key parameters, including drybulb and wetbulb temperature threshholds, data center load, Power Usage Effectiveness (PUE) and cost of electricity. The tool generates an estimate for the number of hours of use for either air-side or water-side economizers a data center operator could expect annually, as well as estimated savings.