Data Center Knowledge pointed out due to the permiting process for Google's data center in Council Bluffs, Iowa, you can see that there are 38 diesel generators permitted for the facility with a rated power of 2919 bhp (2 megawatt)

Emission Unit(s):
1430 W. South Omaha Bridge Rd.
Council Bluffs, IA 51501
200001
Equipment Location:
None
Emission Point:
Diesel Engine (EU 200001; 2,919 bhp; 137.9 gallons/hr)
Control Equipment:

Also, Data Center Knowledge has pointed out the backlogs for generators and new FCC requirements for cel networks are putting strains on the supply of generators.

"Generator lead time for a nice 2 megawatt diesel engine is now up to a year for one generator," Josh Snowhorn of Terremark said in a panel at the NANOG conference earlier this year. "So we can build all the raised floor we want, and then sit around and wait six months for a generator."
In an effort to keep phone and wireless networks online during natural disasters, the FCC is now requiring telecom and wireless companies to provide backup power for cell sites and remote telecom facilities.