When you're sizing an office with a lot of computers, you include the BTU/hr specs given by computer manufacturers.

Every watt going into any device produces a watt of heat.

Let's say you have two computers always going consuming a total of 400W, which comes out to 288kWh/mo.

For the purpose of calculating expense contribution, how much additional kWh do you allocate for each kWh of heat produced? Is it reasonable to assume COP is around 3 and use 1 to 3 ratio?