Smell rubber burning? It's my brain... Here's the thing. Commercial building. We are using on average 280,000 Kwh per month. 480V, 277V, 120V, 240V, single and three phase scattered about the building. I'm trying to figure out what reserve capacity we may or may not have on the standby generator when running in the emergency mode. I have the panel calculations from the prints and some panels aren't on generator power. Not much has changed in the building since the original build-out, and I have redlined the prints as the changes occured. I need just a general ball park caculation to let the powers that be know when we need to upgrade. I recomended that we have a load survey performed, but $$$ is always a problem .... until they have to throw it at a problem that could have been solved or at least identified much earlier. Can I add up the panel loads, subtract the non supplied panels and get close? The Generator is 1875 kVA 1500KW 277/480.