Residential Time-of-Use TRREST - Three Phase
When does peak hit on Tucson Electric Power Co’s Residential Time-of-Use TRREST - Three Phase? Peak hits 6am–10am, 5pm–9pm, 9pm–6am, 10am–5pm in Oct–Apr; 3pm–7pm in May–Sep — every day.
- peak19.17¢
- mid13.14¢
- off-peak11.98¢
What does Residential Time-of-Use TRREST - Three Phase cost a year?
| Household | Uses | Per year | Works out to |
|---|---|---|---|
| Apartment One or two people, no central air, no electric heat | 4,866 kWh | $929 | 19.1¢ / kWh |
| Family home Three or four people with central air conditioning | 9,453 kWh | $1,548 | 16.4¢ / kWh |
| Home with an EV Same house, plus an electric car charging overnight | 13,103 kWh | $2,038 | 15.6¢ / 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 | 19.17¢ up to 500 kWh20.48¢ up to 1000 kWh21.21¢ | 3pm–7pm, May–September |
| mid | 13.14¢ up to 500 kWh14.44¢ up to 1000 kWh15.17¢ | 6am–10am, 5pm–9pm, October–April |
| mid | 12.28¢ up to 500 kWh13.58¢ up to 1000 kWh14.32¢ | 9pm–6am, 10am–5pm, midnight–midnight, October–April |
| off-peak | 11.98¢ up to 500 kWh13.28¢ up to 1000 kWh14.01¢ | 7pm–3pm, midnight–midnight, May–September |
Plus a fixed charge of $25.44 per month.
Should you be on Residential Time-of-Use TRREST - Three Phase?
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 19.2¢ a kWh; at the best hour, 12.0¢ — 1.6× 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 3pm to midnight is about $26 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.
There is a usage cliff to watch. The first 500 kWh each month are billed at 12.0¢; past that line the rate steps up to 13.3¢ — 11% more for every unit after. The last kilowatt-hour of a heavy month is the expensive one, which is why cutting a little off a big month saves more than cutting the same amount off a small one.
Before a single kilowatt-hour moves, this plan charges $305 a year in fixed fees. On the apartment above that is 33% of the whole bill; on the house with a car charging in it, 15%. 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 $178 in July and $100 in February — a $78 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.
How it compares to Tucson Electric Power’s other plans
Measured against the other residential plans this utility files, a family home lands 11th cheapest of 12. The cheapest option, Residential Demand Time-of-Use TRRESDT - Single Phase, would run about $551 a year less.
Against Residential Electric Service TRRES (Single Phase), which looks like the plan you land on by default, this one comes out $1 more per year (0%). We infer the default from the tariff structure rather than a flag in the data, so confirm it against your own bill before you switch.
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.
- What is a baseline allowance? Tiered electricity rates explained
A cheap allowance, then a cliff. Where the cliff sits is the whole game.
- 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.
Where this comes from
- Effective
- 2025-09-30
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://docs.tep.com/wp-content/uploads/102-TRREST.pdf