'Free Cooling' works well in colder climates such as those found in Belgium. A larger fan on the server might be a cheaper solution. Direct air in the racks rat

'Free Cooling' works well in colder climates such as those found in Belgium. A larger fan on the server might be a cheaper solution. Direct air in the racks rather than the room can also be more effective. Since in the evenings air is normally cooler, this can also be used effectively by adding more 'mass' in the room. Anyone thought of having these datacenters on mountains?