Environmentally sustainable Axpo Informatik AG data centers

The reduction in the number of physical servers in the data center due to consolidation and virtualization brings about considerable savings in energy and cooling costs. Furthermore, this approach may contribute to a reduction in expensive data center upgrades and building expansions which would otherwise be necessary to satisfy the rising energy and cooling requirements of modern data centers. This measure allows Axpo Informatik to respond more quickly and more flexibly to changes in general conditions. Since implementation takes a number of years, Axpo Informatik has made do in the meantime with less expensive, structural measures.

The cold aisle containment is attributable to the fact that the active hardware in the racks takes in cold air at the front of the cabinet for cooling purposes. Following cooling, this air is output through the back of the rack as warm exhaust air. This warm air rises within the body of the rack and flows back to the cooled area at the front of the rack. The warm air can also recirculate through unsealed height units in the rack or into the cooled area at either edge of the cabinet. This causes a thermal increase process to occur, gradually leading to a rise in temperature in the cold aisle. This could ordinarily only be counteracted by stepping up the output from the cooling systems, leading to a huge rise in energy consumption throughout the data center.

Therefore, it is essential that the warm air is shielded from the cold aisle between the fronts of the racks by means of an hermetic seal. Measurements have shown that at a constant cooling output there was a 10 to 15 degree difference between the temperatures in the warm and cold aisles. Depending on size and on spatial conditions in various data centers, the cooling output of the systems could be reduced by up to 30 percent in the process. This gives rise to an equivalent saving in energy of approx. 15 percent.