The "Seasonal" part of the description is not useful for developing diversity factor. The diversity factor is supposed to provide a measure of the maximum concurrent load. Maximum load will likely occur when the hotel is fully booked. Guessing that occupancy load will be "diverse" from the HVAC load due to season, is unlikely to lead to a useful conclusion.
If this is an IEC application see the applicable IEC standard
The Canadian cod uses "Demand Factors".
I looked at the section of our code (Circuit Loading and Demand Factors) and rather than summerise the many rules, I suggest that you obtain and study the relevant code.
It is not a difficult question, but neither is it a simple question.
-------------------- Ohm's law
Not just a good idea; It's the LAW!
On the marine side we have classification societies that outline how to use load factors to estimate capacity. Their rules don't work. Do not construct to their standards.
You said you have a tourist season. That's when you make money. You can't afford downtime. Estimate your loads based on tourist season (worst case). You can't make money when you don't have power.
