Need help with calculating the 30‐min annual maximum demand on the substation transformer. One of the distribution transformers of a substation supplies three primary feeders. The 30‐min annual maximum demands per feeder are,

Feeder Demand, kW PF
1 2800 0.95
2 3000 0.85
3 3000 0.90

A diversity factor of 1.15 among the three feeders for both real power (P) and reactive power (Q). I need to calculate the 30 min annual max demand on the Substation TX.