There are various advantages of using server consolidation
Testing of software becomes simple as you need not require costly server farms to load or stress test your applications.
Cost of testing and pre deployment procedures goes down drastically.
In existing infrastructure maintenance of the systems become easier
Disaster Recovery ( DR ) and Business Process Continuity ( BPC ) becomes easier as small number of processes are involved
The cost of real estate goes down as a result of server consolidation
Business resources become Fluid and any reallocation of work or load balancing and resource allocation becomes easier with the above arrangement.
Cost of maintenance goes down with Shared resources like HVAC arrangements which is slightly offset by higher dissipation of heat by powerful servers.
Redundancy can be achieved without hefty budgets.
Redundant capacity can be utilized more efficiently by Utility service Providers.