ComEd Hourly Pricing: Turning Daily Wholesale Rates Into Savings

Most utilities use time-of-use pricing: fixed price blocks that are the same every day. ComEd’s Hourly Pricing program is different and it’s worth understanding, because it rewards automation more than almost any rate in the country. Instead of a few fixed blocks, you pay the actual wholesale market price, and that price changes every hour, every day.

This guide explains how Hourly Pricing works, why it’s a great fit for a smart home, and how to capture the savings you can’t realistically chase by hand.

How ComEd Hourly Pricing works

On the standard fixed rate, you pay one supply price no matter when you use power. On ComEd’s Hourly Pricing program, you pay the hourly wholesale market price set by the regional grid operator (PJM), plus the same delivery charges, taxes, and fees every ComEd customer pays — roughly 8¢/kWh on top of the wholesale price.

Two things make this different from time-of-use:

• The price changes daily. Tomorrow’s hourly prices are published the afternoon before, so a cheap 2 a.m. tonight might be a different number tomorrow. There’s no fixed schedule to memorize.
• The swings can be large. Overnight and midday hours are often just a few cents per kilowatt-hour of wholesale cost; hot summer evenings can spike well above that. The shape of the curve is different every day.

A single day on ComEd Hourly Pricing (June 29, 2026): overnight power costs about 2¢/kWh, then the 7–8 p.m. spike jumps to 44¢ and past 60¢. The cheapest and most expensive hours are only hours apart.

Tomorrow’s hourly prices are published the afternoon before. July 1’s day-ahead curve peaks above 60¢/kWh at 6–8 p.m. — seeing that in advance is exactly what lets a schedule plan around it.

That’s the opportunity and the problem in one sentence: the savings are real, but they move.

Where the savings are

Because the cheapest hours shift day to day, the wins come from reacting to each day’s price curve:

• EV charging during whatever the cheapest overnight stretch happens to be tonight. Not a fixed “after midnight” rule, but the actual low point.
• Pre-cooling or pre-heating ahead of the hours your forecast says will be expensive, so your HVAC coasts through the spike.
• Water heating and battery charging timed to the day’s troughs and away from its peaks.

On a fixed time-of-use plan, “off-peak” is the same every day and you can set a static timer. On Hourly Pricing, the best schedule is genuinely different tomorrow than it was today, which is exactly why a static timer leaves money on the table.

How to capture it: by hand vs. automatically

By hand, you’d check tomorrow’s published hourly prices each afternoon, cross-reference the weather, and reprogram your thermostat, EV charger, and water heater accordingly — every day. Almost nobody sustains that. And even if you did, you’d still be eyeballing how much pre-cooling your house actually needs.

Automatically is the whole point of a rate like this. Hungry Machines pulls the next day’s hourly prices, combines them with tomorrow’s forecast plus a custom model of your home, then builds an optimized schedule each night. It charges the EV in the genuine overnight trough, pre-cools just enough to skate past the expensive hours, and times your water heater and battery to the day’s cheapest energy. Then it does everything again tomorrow against tomorrow’s new prices.

Against a day with a steep evening spike, Hungry Machines pre-cools in the cheap morning hours (blue line) and lets the room drift up through the expensive evening — staying inside the comfort band the whole time. Result: 63% off that day’s cooling cost.

A milder day with a smaller spike calls for a gentler pre-cool right before the evening peak. Same limits, same automation, 33% saved. The right amount of pre-cooling changes every day, which is why a static timer leaves money on the table.

In this situation, automation is the only realistic way to capture what the rate offers.

Common questions

Is ComEd Hourly Pricing risky?

Your price follows the market, so a rare price spike could cost more in that hour. The flip side is that you also capture the many cheap hours, and shifting flexible load away from spikes is exactly what reduces your exposure. Automation that reacts to each day’s prices is the best hedge.

How is this different from time-of-use?

Time-of-use has fixed daily price blocks (e.g., expensive 4–9 p.m. every day). Hourly Pricing has a brand-new price for every hour, published a day ahead. There’s no fixed schedule, and the optimal plan changes daily.

Do I need an EV or battery to benefit?

They help most because they’re big, flexible loads, but pre-cooling a home with AC against the daily curve captures meaningful savings on its own.

Next steps

If your utility uses fixed time-of-use blocks instead, the approach is a little different — see our guides for PG&E and SDG&E.

To let your home react to ComEd’s prices automatically, see how Hungry Machines works and sign up now.