Is a Time-of-Use Electricity Plan Worth It?

A time-of-use plan is cheaper when enough electricity is consumed in the lower-price hours to offset the expensive periods. It can be more expensive when air conditioning, cooking or charging remains concentrated at peak times. A low off-peak advertisement is only one part of the tariff.

SMUD’s current residential rates provide a real comparison with a fixed-rate alternative in the same service territory. Prices and hours below were checked in October 2026. They describe this utility’s standard residential options, rather than a national recommendation or rates available from every electricity supplier.

Key figures

• $0.1550 per kWh SMUD summer off-peak electricity charge
• $0.3765 per kWh SMUD summer peak electricity charge
• $0.2189 per kWh SMUD summer fixed-rate electricity charge

The summer tariff has three price periods

SMUD defines summer as June first through September thirtieth. Its standard time-of-day tariff has off-peak, mid-peak and peak energy charges. The fixed-rate option charges the same per-kilowatt-hour amount throughout the day within that season.

Source note: SMUD’s published residential-rate comparison, checked in October 2026. These are standard energy charges; the separate $27 monthly system infrastructure fixed charge and other applicable bill items are excluded. SMUD lists its current hydrogeneration adjustment at $0.00 per kWh.

• Time-of-day off-peak$0.1550
• Time-of-day mid-peak$0.2139
• Time-of-day peak$0.3765
• Fixed-rate option$0.2189

Source note: SMUD's published residential-rate comparison, checked in October 2026. These are standard energy charges; the separate $27 monthly system infrastructure fixed charge and other applicable bill items are excluded. SMUD lists its current hydrogeneration adjustment at $0.00 per kWh.

Peak hours are weekdays from five to eight in the evening. During summer, mid-peak runs from noon to midnight on weekdays except for the peak period. Other hours, including weekends and holidays, are off-peak. Confirm the utility’s holiday calendar rather than assuming every day off work changes the tariff.

The summer peak rate is 22.15 cents above off-peak. Moving one hundred kilowatt-hours from peak to off-peak therefore saves $22.15. Moving the same amount from mid-peak to off-peak saves $5.89. Both calculations shift consumption; neither requires a reduction in total energy use.

The same monthly use can produce opposite results

Consider a hypothetical summer month using one thousand kilowatt-hours. If six hundred are off-peak, two hundred fifty are mid-peak and one hundred fifty are peak, the time-of-day energy charge is $202.95. The fixed-rate energy charge is $218.90, so time-of-day saves $15.95 before common bill items.

Now keep total use at one thousand but move another one hundred fifty kilowatt-hours into peak time. Off-peak becomes four hundred fifty, mid-peak stays two hundred fifty and peak becomes three hundred. The time-of-day energy charge rises to about $236.18, which is $17.28 above the fixed option after rounding.

Including the common twenty-seven-dollar fixed charge gives $229.95 for the first time-of-day example and $245.90 for fixed. In the second example, time-of-day is about $263.18. The fixed charge changes the bill total but cancels out when comparing these standard plans because both carry it.

These examples do not predict a household’s distribution. Obtain interval data from the utility account and sort it into the tariff periods. Annual kilowatt-hours alone cannot show how much usage occurs during the most expensive three weekday hours.

Winter has a different break-even point

The non-summer standard time-of-day tariff has two periods. Off-peak is 12.85 cents and peak is 17.76 cents, while fixed is 13.71 cents. The difference between peak and off-peak is 4.91 cents per kilowatt-hour.

For the time-of-day energy charge to equal fixed, the peak fraction solves 0.1285 plus 0.0491 times the peak share equals 0.1371. That gives about 17.5 percent peak use. Below that share, the standard time-of-day energy charge is lower; above it, fixed is lower, assuming the published rates and excluding other differences.

This is a two-period non-summer calculation. It cannot be copied into summer, where mid-peak adds another price. Nor does a low winter peak share prove that an entire year’s time-of-day bill will be lower. Weight each season by the energy used in it.

The summer thermostat guide explains why changing a cooling schedule does not guarantee a fixed percentage saving. The appliance running-cost guide helps convert appliance energy into the tariff’s time periods.

Special rate options are separate comparisons

SMUD also offers a low-use option with different energy charges and a seventeen-dollar monthly fixed charge. Its published conditions include a panel rated at 125 amps or smaller and use below 270 kilowatt-hours per month. The lower fixed charge does not mean its energy rates equal the standard table.

The utility lists an electric-vehicle discount of 1.5 cents per kilowatt-hour between midnight and six in the morning for customers who register their qualifying plug-in vehicle. That discount has eligibility and plan conditions. Do not apply it to every customer merely because an overnight period exists.

Critical Peak Pricing is another separate option. SMUD’s comparison lists a fifty-cent-per-kilowatt-hour event addition on top of the price of the time period when the event occurs. It is not a total event rate of fifty cents. A plan with event charges requires its own event-hours and notification analysis.

Those options can change the result, but mixing their best features into one invented tariff produces a misleading comparison. Obtain the schedule for the offered plan, including enrollment conditions and switching rules. Keep standard, low-use, vehicle and critical-peak calculations separate.

The household schedule determines what can move

Move flexible consumption rather than assuming every load is flexible. Charging and laundry may shift, while occupied-hour cooling, meal preparation or medical equipment can be constrained. A timer should not create a safety problem just to capture a lower rate.

Solar exports introduce another distinction: export compensation is not automatically the avoided retail price. The solar ownership comparison explains why self-consumed generation and exported generation require separate values.

Run the previous year’s interval usage through both offered tariffs before switching, then model only changes the household can sustain. A tariff that saves fifteen dollars in a favorable sample month may lose more in hot peak-heavy months. The strongest comparison includes summer, non-summer, fixed charges and eligibility conditions together.

Questions people ask

How much does moving 100 summer kWh from peak to off-peak save?

At the cited SMUD standard rates, the difference is $0.2215 per kWh, so shifting 100 kWh saves $22.15 in energy charges.

Does the $27 monthly charge disappear on time-of-day pricing?

No. SMUD lists that system infrastructure fixed charge for the standard options. It remains in both example totals even when consumption moves between periods.

What is the non-summer break-even peak share?

Using the cited two-period rates, about 17.5% peak consumption makes the time-of-day energy charge equal to fixed. Summer has three periods and requires a different calculation.

Can I compare plans using only total monthly kWh?

Not reliably. Time-of-day billing depends on when those kilowatt-hours occur. Use interval data and the utility's exact periods, season dates and holiday rules.

Where these figures come from

1. Residential Rates: Standard and Special-Option Price Comparison Sacramento Municipal Utility District · smud.org
2. Time-of-Day 5–8 p.m. Rate Sacramento Municipal Utility District · smud.org
3. Residential Fixed Rate Sacramento Municipal Utility District · smud.org

Figures last checked October 2026.