Running the dishwasher at midnight to save money is one of the most repeated pieces of household advice, and for a large share of households it saves exactly nothing. Whether it works depends entirely on one thing that has nothing to do with the appliance: what kind of electricity tariff you are on.
The question that decides everything
Electricity is billed in one of two broad ways. On a flat rate, every kilowatt hour costs the same at every hour of the day. On a time of use tariff, the rate changes according to the clock, typically with an expensive block covering late afternoon and early evening and a cheaper block overnight.
If you are on a flat rate, shifting a load to 2am changes your bill by zero. The energy is the same, the price is the same, and the only thing you have altered is when the noise happens. That is a legitimate reason to do it, but it is not a saving.
Check your bill for more than one rate line, or for a plan name containing words such as time of use, time of day, or peak and off peak. Many utilities offer these as an opt in rather than a default, so you may be eligible and not enrolled. Some also run a separate demand charge based on your highest fifteen minute draw in the month, which rewards not running several heavy appliances at once regardless of the hour.
The arithmetic, worked as an illustration
The rates below are round illustrative figures chosen to make the calculation legible. They are not a quotation of any real tariff, and your own numbers are on your bill.
| Energy per run | Cost at 30 cents peak | Cost at 10 cents off peak | Saving per run | Saving over 300 runs |
|---|---|---|---|---|
| 0.1 kWh | 3 cents | 1 cent | 2 cents | about 6 dollars |
| 1.0 kWh | 30 cents | 10 cents | 20 cents | about 60 dollars |
| 2.5 kWh | 75 cents | 25 cents | 50 cents | about 150 dollars |
| 4.0 kWh | 1.20 dollars | 40 cents | 80 cents | about 240 dollars |
The shape of the table is the lesson. The saving is proportional to the energy in the run, so shifting a coffee maker is pointless and shifting a dryer is not. Anything that heats water or air is worth moving. Anything that does not is noise.
What is actually worth shifting
In descending order of energy per run, and therefore of payoff:
- Electric dryers. The largest single shiftable load in most homes, since the entire cycle is a heating element and a blower.
- Washing machines on a warm or hot cycle. The heating is the cost, so a cold wash has much less to shift.
- Dishwashers. Water heating plus heated drying, and they run unattended by design.
- Electric water heating and vehicle charging. Not appliances in this catalog, but they dwarf everything above.
- Everything else. Coffee makers, microwaves, blenders and kettles use too little per run for the timing to matter.
Which machines here can actually do it
A delayed start needs to be a feature of the appliance, and it is reported unevenly across these listings. On the dishwasher side, the Sharp SDW6757ES lists a delay function alongside its touch panel, which is the straightforward version: set a number of hours, walk away.
On laundry, the capability usually arrives through connectivity rather than a dedicated dial. The LG WashTower is listed with app control as its controller type, the LG WKGX201HBA lists a remote controller, and the LG WM4500HBA is listed with smart connectivity, as is the GE GFW850SPNRS. The GE GFD55ESSNWW dryer lists Wi-Fi. What none of the listings state is whether the app offers a true scheduled start or only a remote start you trigger yourself, and that distinction decides whether the feature is useful for tariff shifting at all. It is worth confirming before buying on that basis. The broader set of washers here divides fairly cleanly between connected and mechanical models.
Delay timers that are not about money
Two categories here carry prominent timers that have nothing to do with electricity rates, and it is worth not confusing them.
Bread machines use a delay timer so the loaf finishes at breakfast. The Zojirushi BB-PDC20BA, listed at 700 watts with seven programs, and the Breville custom loaf machine at 830 watts with thirteen programs, are both built around that pattern. The energy involved is small, so the timer is a convenience feature. It also carries a genuine caution that has nothing to do with cost: a delayed start leaves the ingredients sitting in the pan for hours, and recipes containing milk, eggs, cheese or fresh dairy should not be left at room temperature that way. Use the timer with dry ingredients and water, not with perishables.
Programmable coffee makers are the same idea with even less energy at stake. The Cuisinart 14 cup programmable machine and the Bella 35203, which lists auto shut off and a cup warmer, will not move your bill by scheduling. What does move a coffee maker’s annual consumption is the warming plate running for two hours after the brew, and that is an auto shut off setting rather than a start time. Across the bread machines here, timers are standard and energy figures are rarely given.
The reasons not to
Unattended overnight operation is not free of risk, and the honest advice is that this is a judgment call rather than a clear win.
- Dryers and lint. A blocked vent or a full lint filter is a fire risk, and a dryer running while everyone sleeps is running with nobody to notice a problem. If you shift one load to overnight, shift the vent cleaning schedule with it.
- Washer and dishwasher leaks. A hose failure at 3am floods for hours before anyone sees it. Steel braided hoses and a periodic look at the connections cost less than the alternative.
- Damp laundry. A wash that finishes at 4am and sits in the drum until morning develops a smell that costs you a rewash, which wipes out the saving completely.
- Noise. Everything in the article on washer and dryer noise and vibration applies with more force when the house is quiet and neighbors are asleep.
- Manufacturer guidance. Some manuals advise against unattended operation. That is worth reading before building a routine around it.
If you have solar, the advice inverts
For a household with rooftop panels and an unfavorable export rate, the cheap electricity is the power you generate and use yourself, and that arrives in the middle of the day. Shifting the dishwasher and the dryer to midday rather than midnight is the right move, and running them overnight is the expensive option. This is the clearest case of generic advice being wrong for a specific household, and it is worth checking which situation you are in before setting any timer.
The short version
Find out whether your rate varies by time. If it does not, off peak running saves nothing and you should schedule on convenience and noise instead. If it does, move the dryer first, the hot washes second and the dishwasher third, and leave everything else alone. Then spend the attention you saved on the settings that reduce the energy itself, because a load that never gets heated costs nothing at any hour.
