We do some work at a sugar plant and they have "MCC" rooms that have motor controllers, circuit breakers, disconnects, and so on that all generate heat. A lot of heat. We are trying to do away with conventional AC with ducts and air handlers and stuff and go with refrigeration style evaps in the rooms...essentially treat each room as a walk in. How in the world do you figure heat gain for electrical controllers? We took an amp draw from one of the lines coming in and had 170 amps at 460 volts but the motors aren't actually in the room...just the controllers. They generate a lot of heat, but how do we figure how much?