Load difference between the same type of Gas turbines against same compressor discharge temperature and pressure.

we have two westinghouse W250B11 gas turbines with each 50MW rating.
we named one as GT-1 and the other as GT-2.
GT-1 reach load upto 47MW
While GT-2reach up to 50MW at the same ambient temperature and pressure.
both compressor efficiency is the same.
compressor discharge pressure and temperature is also the same.
Exhaust temperature is also same.
only blade path temperature difference is 10F.
GT1 has lower Blade path temperature..

please tell me why GT-1 produce 3 MW low load?

[email protected]