What Are Time-of-Use Rates?

Time-of-Use (TOU) electricity pricing charges different rates depending on when you use electricity. During peak demand hours — typically weekday afternoons and evenings when everyone gets home from work — rates are higher. During off-peak hours — nights, early mornings, and weekends — rates are lower.

The spread between peak and off-peak rates varies significantly by utility and state:

  • California (PG&E EV2-A): Off-peak $0.12/kWh, Peak $0.58/kWh — spread of $0.46/kWh
  • Connecticut (Eversource): Off-peak $0.14/kWh, Peak $0.42/kWh — spread of $0.28/kWh
  • Texas (ERCOT): Off-peak $0.08/kWh, Peak $0.28/kWh — spread of $0.20/kWh
  • National average: Off-peak $0.10/kWh, Peak $0.26/kWh — spread of $0.16/kWh

How Plug-In Solar + TOU = Maximum Savings

Standard plug-in solar saves you money by generating electricity from sunlight and using it instead of grid power. With TOU optimization, you can do much better:

  1. Charge the battery during off-peak hours (midnight to 6am) at $0.10/kWh
  2. Discharge the battery during peak hours (4–9pm) to avoid paying $0.26–$0.58/kWh
  3. Solar generation during the day charges the battery for free (after amortizing system cost)

In California with PG&E's EV2-A rate, a system that charges at $0.12/kWh and displaces $0.58/kWh peak power effectively earns $0.46/kWh in savings — nearly 4x the national average rate.

Which Systems Have TOU Scheduling?

All major plug-in solar systems now include TOU scheduling in their apps:

  • Premium systems: Excellent TOU scheduling with automatic peak/off-peak optimization
  • Mid-range systems: Good TOU scheduling, may require more manual configuration
  • Grid-interactive systems: Strong TOU features with grid interaction capabilities
  • Basic systems: Standard TOU scheduling — functional but may require more manual setup

How to Check If You Have TOU Rates

Log into your utility's online portal and look for "Rate Plan" or "Rate Schedule." Most utilities now offer TOU as an option, and some are making it the default for new customers.

If your utility offers TOU, switching is usually free and can be done online. Most plug-in solar system apps include a TOU configuration screen where you enter your specific peak/off-peak hours and rates.

Is TOU Right for You?

TOU rates work best if you can shift significant electricity consumption to off-peak hours. If you work from home and use electricity heavily during peak hours, TOU might not save you money without a battery system to buffer the peak charges.

With a plug-in solar system, TOU almost always makes sense — the battery handles the peak/off-peak arbitrage automatically.