When the Heat is On

A Letter from the President

Simon S. Whitelocke is the Vice President of ITC Holdings Corp., and President of ITC Michigan.

Remember those late September days when temperatures in Michigan soared above 90 degrees for nearly a week? It was unseasonably warm for the first few days of fall, and that contributed to some unique system conditions for the grid. I’m pleased to say that ITC’s transmission systems performed exceptionally well under these conditions, despite a number of challenges:  significantly higher than forecasted load (electricity use), a large amount of unavailable generation and a significant number of planned outages.

September loads are typically lower than peak summer loads, ranging anywhere from 12,000 to 15,000 megawatts. Transmission and generation owners often take this opportunity to schedule system maintenance activities. In early September, ITC engineers studying the late September timeframe estimated a load of ~15,200 megawatts, and planned our maintenance outages accordingly.

On Sept. 26, when the thermometer hit 90 degrees in Metro Detroit, there were ~40 planned maintenance outages in progress across our Michigan systems, including the tie-lines connecting the regional and Michigan systems to Ontario, which significantly reduced our ability to import power. At the same time, there were ~2,600 megawatts of generation on planned outage. And actual load came in 3,000 megawatts higher than originally estimated.

As expected on any hot day, there was market congestion encountered throughout the region. ITC took action to help mitigate this congestion by putting some lines and equipment back into service. We worked closely with the Midcontinent Independent System Operator (MISO) throughout the heat wave and imported anywhere from 3,800 to 5,335 megawatts of electricity into Michigan to meet demand.

These unique conditions demonstrated that once again, whether faced with fluctuating temperatures, changing consumer demands, or intermittent resources such as wind or solar generation, the flexibility of a strong, regional transmission system is key to delivering reliable and economic energy to Michigan.  


Simon S. Whitelocke
Vice President, ITC Holdings Corp. and President, ITC Michigan