A method, apparatus, and system are disclosed for determining a size of a utility date center. In one embodiment, a computer system includes a bus, a computer-readable memory coupled to the bus, and a processor coupled to the memory via the bus. The processor executes code for calculating, based on historical usage data, resource usage for a plurality of different applications of a plurality of servers in the utility data center (UDC); calculating, for each server, penalties imposed against the UDC and penalties imposed against at least one user of resources of the servers; and calculating a number of servers required to make the UDC profitable.