Quote Originally Posted by Russix View Post
When my brother worked at the then GM Building in New Center, Detroit Edison would call up on hot days during the summer and ask them to close down for the day because all the window ac units were taxing the hell out of the electrical grid.
Correct and incorrect.

The reason this occurred is that many mfg companies with a number of facilities work out deals with the utility companies. They receive a reduced rate for their electricity but the provider also has the right to request that they shed load during peak usage. Essentially DTE could request that they shut down any non-critical facilities to reduce load. This deal applied to all facilities that receive electricty from the provider. It was not unique to that building.