On Hourly Pricing, not all hours are equal, and a small number of them carry most of the risk and most of the opportunity. Those hours are hot summer weekday afternoons, and they matter for two separate reasons at once.
When are ComEd hourly prices highest?
For most of the year, prices on Hourly Pricing stay relatively low. Fall, winter, and spring are usually calm, with occasional spikes during extreme weather. The exception is summer. When it is hot across the region and air conditioners run everywhere at once, wholesale prices climb, and the highest prices of the year tend to land on weekday afternoons, roughly between 2 and 6 p.m. A single hot afternoon can cost more than many ordinary days combined.
How the ComEd capacity charge is set
Starting in June 2026, those afternoons matter a second way. The capacity charge on Hourly Pricing bills is tied to how much power your home draws during the grid's highest demand summer hours. Like a commercial demand charge, it is set by your draw at the peak, not by your total monthly energy. So the same summer afternoons that carry the highest energy prices also decide a separate line on your bill.
What that means for the shape of the year
The practical consequence is that your Hourly Pricing outcome is decided by a thin slice of the year, not spread evenly across it. Doing well in the mild months is easy and matters little. What separates a home that saves from a home that pays more is almost entirely what happens on those summer afternoons: how much load lands in that window, and whether any of it is flexible.
Does this apply to your home?
None of this tells you what to do, because the answer depends on your house. A home with little summer-afternoon load may barely notice these hours. A home running heavy air conditioning through them may be exposed on both the energy price and the capacity charge. The only way to know which one you are is to look at your own usage during those hours against what they actually cost, which is a reconstruction of what already happened, not a guess. We are building an independent tool to do exactly that on your ComEd data, with no commission and nothing to sell.
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