If you have a machine dishwasher, I’ve got some bad news for you: You’re probably choosing the most expensive time of day to run it.
Assuming you’re like me, you probably prefer cleaning up right after dinner so you don’t forget, thus avoiding a large pile of dirty dishes. Or if you do forget, you might turn on the dishwasher first thing in the morning before work so you have clean dishes ready at the end of the day.
Unfortunately, most of the population has the same philosophy when it comes to using their dishwashers. The moments immediately after dinner and first thing in the morning are peak hours in many locations, and that means energy usage is more expensive.
To circumvent those busy, high-priced times, consider taking advantage of the timer feature on your dishwasher to delay the start time until off-peak hours (generally during the late morning or early afternoon).
According to the Pacific Gas and Electric Company (PG&E)—one of the largest combined natural gas and electric energy companies in the United States—peak pricing is either between 4 p.m. and 9 p.m. or 5 p.m. and 8 p.m. Monday through Friday, depending on location. Weekends and holidays are off-peak hours, as are most weekday hours before 5 p.m.
Depending on the peak hours in your location, you could save yourself some moolah by reducing your energy usage during those higher-priced hours.
PG&E suggests getting your dishes loaded and your clothes ready for the washer/dryer during those peak times, then waiting until lower-priced off-peak times to actually run your appliances. Those off-peak times, though, shouldn’t necessarily include overnight.
Scott Wolfson from the Consumer Product Safety Commission told The New York Times that running big appliances overnight isn’t a great idea because there’s a slight chance of fire. It’s common for appliances to feature fail-safe technology; in fact, your dishwasher probably has a cutoff switch to power down in case of overheating.
However, there’s always a slight risk with running appliances overnight. Wolfson warned that there may be times when fail-safes aren’t enough, and you may be required to personally intervene by unplugging the appliance or taking other direct measures.
The risk of fire may be rare, but it’s worth considering. For what it’s worth, PG&E offers conflicting advice, recommending that you run your dishwasher and washer/dryer overnight to save money. But our ultimate advice to save money and stay safe is to use your dishwasher’s timer feature.