Midwest Energy Cooperative is urging customers to dial back air conditioners and reduce energy use in other ways. A spokeswoman said on Thursday, July 21st, that some parts of the region are under a "power emergency event" due to high demand caused by the lingering heat wave. She says if demand isn't reduced voluntarily, some customers may lose power as utilities cut loads to protect the region's power grid.

In a news release, Consumers Energy is asking its customers to limit energy use so it can meet the demand to run air conditioning in response to high heat and humidity.

A spokesman for Indiana and Michigan Electric says it always recommends energy conservation. But he says the utility isn't asking customers to limit power use yet.

Consumers Energy hasn't said if it is having any problems keeping up with demand.