Palo Alto residents can opt into an electricity rate that charges less during daytime hours and more in the evening, but the city's own data shows average households would pay more unless they change when they use power.

City of Palo Alto Utilities opened enrollment for the Time-of-Use rate, designated E-1-TOU, on Jan. 1. The utility promoted the option on X on Sept. 17, encouraging residents to shift energy use to midday hours. The rate differs from the standard E-1 plan's tiered pricing, which charges the same rate regardless of time of day but increases per kilowatt-hour at higher usage levels.

Under the TOU rate, electricity costs the most during peak hours of 4 p.m. to 9 p.m. daily and the least during "super off-peak" hours of 9 a.m. to 3 p.m., when excess solar power floods California's grid. A mid-range "off-peak" rate applies from 3 to 4 p.m. and 9 p.m. to 9 a.m.

Here's the trade-off. CPAU's bill comparison data shows a household using 450 kilowatt-hours per month, roughly the city average, would pay about $3.77 more per month on the TOU rate without changing habits. Higher-use households fare better. A home using 800 kWh monthly would save $1.61, and a home at 1,600 kWh would save $13.91.

The savings hinge on running dishwashers and laundry so they finish before 4 p.m. or start after 9 p.m., and charging EVs during the 9 a.m. to 3 p.m. window for the biggest savings, and avoiding heavy electricity use between 4 p.m. and 9 p.m.

Unlike PG&E and many other California utilities, CPAU has no plan to make time-of-use rates mandatory, according to the utility's rate page. The program remains voluntary.

CPAU says the environmental case goes beyond individual bills. Palo Alto's electricity supply is carbon neutral on an annual basis, but the city buys from the state's hourly market in real time. Shifting demand to midday, when solar generation peaks, means the statewide grid relies less on fossil-fuel plants during the evening.

Not every household qualifies. Residents must live in a separately metered single-family home, have an Advanced Metering Infrastructure smart meter installed and not be on a net-energy-metered rate with rooftop solar or battery storage.

Customers who enroll must stay on the TOU rate for at least six months. After switching back to E-1, they must wait 12 months before re-enrolling.

CPAU will run a personalized bill analysis for residents considering the switch. Customers can email their address to [email protected], and the utility will review six to 12 months of usage data to estimate the impact. Exact per-kilowatt-hour rates vary by season; the full rate schedule is posted on the CPAU enrollment page.

Enrollment is open with no announced end date. Residents can sign up through the online form on the city's rate page or call CPAU at (650) 329-2161.