I am not an expert, but it's a fact that any electricity consumed by the games will eventually turn into heat. Looking at your game list, I would guess that their total average power consumption is about 6 kW. The internet says 1 ton of cooling is about 3.5 kWh, which means the games should require nearly 2 tons of cooling. Another 2 tons for people, 1 ton for whatever else, and you're good to go.
This is a very rough estimate, but it's how I would look at it.