Understanding Time-of-Use Rates and How to Optimize Your Home for Savings

What if you could cut your electricity bill by 15-25% just by shifting when you use power? That's the promise of time-of-use (TOU) pricing—electricity rates that vary based on the time of day, reflecting the actual cost of generating and delivering power during different periods. When demand is low, prices drop. When demand peaks, prices rise.

For Illinois residents willing to adjust their habits, time-of-use rates offer a genuine opportunity to save money while reducing stress on the electrical grid. But TOU pricing isn't right for everyone, and understanding the details is crucial to determining whether it makes sense for your household.

Paying More For Power After 4 PM? Decoding Illinois's Time-of-Use Rates

Time-of-use pricing reflects a fundamental reality of electricity: it costs more to generate and deliver power when everyone wants it simultaneously than during low-demand periods.

Why Electricity Prices Vary by Time

During peak demand periods—typically hot summer afternoons when air conditioners run full blast—utilities must activate their most expensive "peaker" power plants. They may also need to purchase expensive power from neighboring regions. All this drives up the wholesale cost of electricity.

During off-peak periods—nights, early mornings, and weekends—demand is lower, and utilities can rely on their most efficient, lowest-cost generation. The grid has spare capacity, and wholesale prices drop accordingly.

Time-of-use rates pass these cost variations through to customers, creating incentives to shift usage away from expensive peak periods.

TOU Rate Structures in Illinois

Illinois utilities and alternative suppliers offer various time-of-use options:

ComEd Hourly Pricing: Under this program, your electricity supply price changes every hour based on the real-time wholesale market. Prices are lowest in the middle of the night and highest during afternoon and evening hours on hot days. According to ComEd's hourly pricing program, participants who actively manage their usage have saved an average of 15% compared to fixed-rate supply.

Supplier Time-of-Use Plans: Some competitive energy suppliers offer structured TOU plans with set peak and off-peak rates, providing more predictability than hourly pricing while still offering savings opportunities.

Electric Vehicle Charging Rates: Special rate structures designed for EV owners often include very low overnight rates when vehicles typically charge.

The Secret Savings Schedule: Mapping Out Illinois's Peak vs. Off-Peak Energy Hours

To take advantage of TOU rates, you need to understand when prices are high and when they're low.

Typical Peak and Off-Peak Periods

While specific hours vary by program, typical patterns for Illinois TOU rates include:

Important: Always verify the specific hours for your rate plan. Periods can vary by program, season, and whether you're on utility service or a competitive supplier's plan.

How Much Can Prices Vary?

The price differential between peak and off-peak can be substantial:

• Typical off-peak rates: $0.03 - $0.06 per kWh
• Typical peak rates: $0.10 - $0.20 per kWh
• Extreme peak (during heat waves): $0.50 - $2.00+ per kWh with hourly pricing

This means running your dishwasher at 3 PM on a hot summer day could cost 3-10 times more than running it at 11 PM.

7 Genius Home Hacks to Crush Your Peak Hour Energy Costs Today

Ready to start saving with TOU rates? Here are practical strategies to shift your consumption to low-cost hours:

1. Master Your Thermostat Scheduling

Heating and cooling typically represent 40-50% of home energy use. Strategic thermostat management is your biggest lever:

• Pre-cool before peak: On hot days, drop your thermostat a few degrees before peak hours (around 1-2 PM). Your home will coast through peak periods while using less AC.
• Allow slight temperature drift: Let your home warm up a few degrees during peak hours, then cool back down in the evening.
• Night cooling: In summer, open windows during cool nights rather than running AC, then close up in the morning to retain the coolness.

2. Shift Laundry to Off-Peak Hours

Washers and especially dryers consume significant energy. Simple shifts make a big difference:

• Run loads before 6 AM or after 9 PM
• Take advantage of weekend off-peak rates for larger laundry sessions
• Consider air-drying during summer months

3. Delay the Dishwasher

Most dishwashers have delay-start features—use them:

• Load the dishwasher after dinner and set it to run after 9 PM or overnight
• Use the "delay start" button on your machine
• Avoid running during afternoon peak hours

4. Cook Strategically

Electric ovens and stovetops draw substantial power. Consider:

• Cook in batches: Prepare multiple dishes during off-peak hours and reheat during peak times
• Use efficient cooking methods: Microwaves, instant pots, and slow cookers use less energy than conventional ovens
• Grill outdoors: In summer, outdoor grilling avoids both cooking heat and AC load

5. Charge Electronics Overnight

Phones, tablets, laptops, and other devices can charge while you sleep:

• Plug in devices after 9 PM rather than when you get home
• Use power strips that can be switched off during peak hours
• Take advantage of device scheduling features

6. Manage Your Water Heater

Water heating is often the second-largest energy consumer in homes:

• Timer controls: Install a timer to heat water during off-peak hours only
• Tank storage: A well-insulated tank stores hot water for use during peak hours without running
• Heat pump water heaters: Highly efficient models reduce consumption regardless of timing

7. Pool Pump Scheduling

If you have a pool, the pump is a major electricity consumer:

• Run the pump during super off-peak hours (midnight to 5 AM)
• Many pool pumps have built-in timers—set them for optimal times
• Variable-speed pumps can run longer at lower power levels during off-peak hours

Beyond the Basics: Is Smart Home Tech Your Key to Ultimate TOU Savings?

While manual scheduling works, smart home technology can automate TOU optimization and maximize your savings with minimal effort.

Smart Thermostats

Devices like Nest, Ecobee, and Honeywell smart thermostats can:

• Learn your schedule and pre-condition your home before peak hours
• Integrate with utility programs to automatically respond to price signals
• Provide energy usage reports to help you understand consumption patterns
• Enable remote adjustments when your schedule changes unexpectedly

For more on these devices, see our guide on smart thermostats giving you control.

Smart Plugs and Outlets

Smart plugs allow you to:

• Schedule when devices receive power (perfect for chargers, small appliances)
• Monitor energy consumption of individual devices
• Control devices remotely via smartphone apps
• Integrate with voice assistants for convenient control

Smart Appliances

Newer appliances often include smart features:

• Smart washers and dryers: Can be scheduled to run during optimal hours
• Smart water heaters: Heat water only during off-peak periods
• Smart EV chargers: Automatically charge your vehicle during the cheapest overnight hours

Home Energy Management Systems

For comprehensive control, home energy management systems integrate multiple devices:

• Monitor whole-home and circuit-level energy usage in real-time
• Automatically adjust multiple systems based on TOU schedules
• Provide detailed analytics on consumption patterns and savings
• Integrate with solar and battery storage for maximum optimization

Is Time-of-Use Right for You?

TOU rates can deliver significant savings, but they're not ideal for everyone. Consider these factors:

Good Candidates for TOU Rates:

• Households where no one is home during peak afternoon hours
• People willing to shift laundry, dishwashing, and cooking to evenings/weekends
• EV owners who charge overnight
• Homes with smart thermostats and automation
• Highly engaged energy consumers who monitor their usage

TOU Rates May Not Be Ideal For:

• Households with daytime occupancy (work from home, retirees, stay-at-home parents)
• Homes without air conditioning (less flexibility to pre-cool)
• Families with fixed schedules that can't shift usage easily
• People who prefer bill predictability over potential savings
• Medical equipment users who can't shift usage times

How to Test Before Committing

Before fully committing to TOU rates:

1. Access your smart meter data through your utility portal
2. Analyze when you currently use the most electricity
3. Use utility calculators to estimate whether TOU would save you money based on your actual usage patterns
4. Consider a trial period if your utility offers one