As a commercial/industrial HVAC guy, sometimes employed by AT&T, this is the norm. There is zero chance that you can identify redundancy from an aerial photo. Often times multiple smaller devices are used to stage up/down for better capacity control, with 25%-50% redundancy for in the event of an equipment failure or during service.
Specifically in this case, AT&T is considered a municipality due to their landlines and 911 operation. They are likely required by law to have 100% redundant HVAC and electrical systems.
As a commercial/industrial HVAC guy, sometimes employed by AT&T, this is the norm. There is zero chance that you can identify redundancy from an aerial photo. Often times multiple smaller devices are used to stage up/down for better capacity control, with 25%-50% redundancy for in the event of an equipment failure or during service.
Specifically in this case, AT&T is considered a municipality due to their landlines and 911 operation. They are likely required by law to have 100% redundant HVAC and electrical systems.