The Cheapest Time to Run Appliances: Time-of-Use Rates Explained

On a flat-rate plan, a kilowatt-hour costs the same at 5 pm as at 3 am, and this guide can’t save you a dime — beyond helping you check whether a time-of-use plan would. But tens of millions of U.S. households are now on time-of-use (TOU) rates, where the same load can cost two to three times more at dinnertime than overnight. California put most residents on TOU by default; Arizona, Texas, Colorado, Michigan, and many others offer or default to them.

How TOU pricing works

Utilities pay wildly different wholesale prices across the day — demand peaks in late afternoon and early evening when everyone gets home, cooks, and cools the house. TOU plans pass that shape on to you, typically as:

• Peak: weekday late afternoon/evening, commonly 4–9 pm. The expensive window.
• Off-peak: overnight and often midday. The cheap window — sometimes half the peak price or less.
• Some utilities add a super off-peak (deep overnight, aimed at EV charging) or seasonal variations.

The gap is the whole game. A plan with 45¢ peak / 25¢ off-peak means a task shifted overnight costs 45% less. Check your utility’s exact windows — they vary enormously.

Which appliances are worth shifting

Shiftability is about two things: does it use a lot of energy per session, and do you care when it runs?

Prime candidates:

• EV charging — the biggest and easiest win. 250–400 kWh/month, fully schedulable from the car or charger. On many TOU plans this alone justifies switching plans.
• Dishwasher — has a delay-start button; nobody cares when dishes wash. 1–1.5 kWh per load, every day, forever.
• Laundry — 3–4 kWh per dryer load. Weekend mornings or after 9 pm.
• Electric water heater — the sleeper hit. A tank stores heat beautifully; a simple timer heating water off-peak can shift 300+ kWh/month without changing a single shower. Some utilities give rebates for controllable water heaters.
• Pool pump — completely schedulable, and one of the biggest loads at homes that have one.

Semi-shiftable:

• Pre-cooling with AC — cool the house harder before the peak window, coast through it a few degrees higher. Works best in well-insulated homes.
• Oven cooking — batch-bake on weekends; use the air fryer or microwave during peak.

Not shiftable, don’t bother: refrigeration, electronics, lighting, and anything tied to when you’re actually using it.

The one-evening setup

1. Find your plan’s exact peak window (bill or utility app).
2. Set the EV to charge starting at the off-peak hour — one-time setting.
3. Make delay-start the default dishwasher habit: load after dinner, start at midnight.
4. Put the water heater on a timer if you’re handy (or ask about utility programs).
5. Shift laundry to weekends/late evening.

Households that shift EV charging plus laundry, dishes, and hot water routinely move 40–60% of their total usage off-peak — often $20–60/month on plans with a wide peak/off-peak spread, for close to zero lifestyle change.

Should you choose a TOU plan?

If you have an EV, almost certainly yes. If you’re home all day running AC at 5 pm and can’t shift anything, possibly not. Pull your hourly usage data from your utility’s portal (most provide it), and compare what last month would have cost on each plan — utilities frequently offer this comparison themselves, and it beats guessing. If your market is deregulated, see our guide to switching providers.