Residential Service Time-of-Day (Single-Phase) ERTD
When does peak hit on Superior Water and Light Co’s Residential Service Time-of-Day? Peak hits 9am–9pm on weekdays, all year.
- peak15.98¢
- mid15.14¢
- off-peak7.60¢
Weekends are off-peak all day — the cheapest time to run anything you can schedule.
What does Residential Service Time-of-Day cost a year?
| Household | Uses | Per year | Works out to |
|---|---|---|---|
| Apartment One or two people, no central air, no electric heat | 4,866 kWh | $680 | 14.0¢ / kWh |
| Family home Three or four people with central air conditioning | 9,453 kWh | $1,209 | 12.8¢ / kWh |
| Home with an EV Same house, plus an electric car charging overnight | 13,103 kWh | $1,487 | 11.3¢ / kWh |
Estimates, not quotes. We run three made-up but realistic households through this tariff hour by hour for a full year — including the way air conditioning loads the afternoon and an EV loads the small hours. Your own bill depends on when you actually use electricity, which is exactly the thing a per-kWh number hides.
What you actually pay
| Period | Rate | Applies when |
|---|---|---|
| peak | 15.98¢ | 9am–9pm, March–October |
| mid | 15.14¢ | 9am–9pm, November–February |
| off-peak | 7.60¢ | 9pm–9am, midnight–midnight |
Plus a fixed charge of $12 per month.
Should you be on Residential Service Time-of-Day?
This is a time-of-use plan, which means the clock decides your bill as much as the meter does. At the worst hour you pay 16.0¢ a kWh; at the best hour, 7.6¢ — 2.1× apart for identical electricity.
That gap is worth real money only if you can move load into it. Every kilowatt-hour a day you shift from 9am to midnight is about $31 a year. A dishwasher run is roughly 1.5 kWh; an EV commute charge is 8 to 12. If your day is fixed — you are home in the evening and the air conditioner runs when it runs — a plan like this costs you more, not less.
Before a single kilowatt-hour moves, this plan charges $144 a year in fixed fees. On the apartment above that is 21% of the whole bill; on the house with a car charging in it, 10%. Fixed charges are invisible in a cents-per-kWh comparison and they punish small users hardest — if you use very little electricity, the headline rate is the least important number on this page.
Expect the bill to move with the calendar. The same family home costs about $142 in July and $76 in February — a $65 spread driven by heating and cooling far more than by anything you chose. Budget against the July figure, not the average, and a summer bill stops being a surprise.
If this is new to you
- What is a time-of-use electricity rate?
The same kilowatt-hour, priced differently depending on when you use it.
- Should you switch to a time-of-use electricity plan?
A wide peak-to-off-peak gap is a lever, not a saving. Levers need something to move.
- When should you charge an electric car at home?
The single biggest load most homes can move, and the easiest to automate.
- Why is my electric bill so high in summer?
Usually three causes at once, and only one of them is your air conditioner.
Where this comes from
- Effective
- 2025-01-01
the date this tariff took effect
- Covers
- delivery + supply
우편번호 매핑에서 이 지역 서비스 종류가 Bundled — 배달과 공급을 함께 판다
- Enrollment
- open to new customers
Tariff document: https://www.swlp.com/customerservice/electricratesextensionrules