If you’re one of the 51% of Garfield County residents who get their electricity from Xcel Energy, you probably received an email recently with the subject line “Time of use is here.”

I recommend that you go back and read that notice. It’s about an important change that can enable you to save some money on your electric bills if you play your cards right – or cost you more if you don’t.

Time-of-use rates are a smart policy, made possible by so-called smart meters. Glenwood Springs Electric and Holy Cross Energy customers have had smart meters for a while, and most Xcel customers in Garfield County have been switched over to them by the utility in the past few months.

These new meters record electricity usage in real time and transmit the data wirelessly, which allows utilities to make better use of grid resources and empowers customers to understand and control when they use energy. (And no, smart meters don’t let the utility control your electricity use. They just measure it.)

Starting with the April 1 billing cycle, Xcel residential customers with smart meters will be automatically signed up for time-of-use (TOU) pricing unless they opt out. Holy Cross also offers a TOU rate structure, but its customers have to opt into it. Glenwood Springs Electric doesn’t currently offer TOU rates despite their use of smart meters.

For electric utilities, time-of-use pricing is a useful tool. Their job is to balance power supply with demand 24/7, but demand varies considerably. It tends to be greatest in the early evening on weekdays, when lots of people come home from work and turn on home appliances, air conditioning, and so on. The effect is more pronounced in summer.

It costs more to deliver electricity during peak demand periods, so it’s in the interest of a utility to move away from flat rates to a variable structure that better reflects the true cost of the electricity. Time-of-use rates will also enable utilities to integrate more renewable energy into their grids.

Fortunately, Xcel’s new TOU rates don’t necessarily mean your electricity bills will go up. In fact, they’re structured so that the extra cost of using electricity at peak times is exactly offset by the extra savings of using electricity at off-peak times.

The way to profit from TOU is to shift more of your heavy-duty electrical loads to off-peak times. The heaviest power draws in your home are air conditioning, clothes drying and (if you have an EV) car charging, so they’re the ones to focus on. I wouldn’t worry so much about cooking with an electric stove or running a dishwasher or washing machine, as they use much less energy. Xcel has a helpful graphic about this.

So see if you can dry your clothes in the morning or on the weekends. Program your AC to cool the house down before the peak period, then to stay off until it’s off-peak again. Wait until the evening peak period is over to plug your EV in.

If you’re an Xcel customer and you decide to go with TOU, you’ll definitely want to familiarize yourself with the new schedule and maybe print it out and put it on your fridge. On weekdays, peak hours are 3 to 7 p.m., off-peak hours are 7 p.m. to 1 p.m., and there’s a “mid-peak” period from 1 to 3 p.m. Weekends and holidays are all off-peak. The schedule will change slightly for the summer season from June 1 to Sept. 30.

Holy Cross’s peak hours are slightly different – 4 to 9 p.m. – and there’s no mid-peak period. Xcel is expected to follow suit and eliminate its mid-peak period later this year.

If you have rooftop solar, time-of-use has extra implications. Your system generates most of its electricity in the middle of the day, which under TOU will earn you less credits. That means you’ll have an even greater incentive to shift your electricity use to your peak production times, and perhaps to invest in battery storage.

Thanks to smart meters, Xcel customers can now log into their account to track their energy usage over the previous eight hours in 15-minute intervals and see how much of it is peak vs. mid vs. non-peak. It can be kind of a fun challenge to experiment and see which changes shift your peak usage the most.

More customers shaving their peaks is indirectly beneficial to all ratepayers because it reduces the amount of high-priced peak energy in the mix, and it also reduces the risk that the utility will have to build more peak-period capacity in the future. A grid that’s making more efficient use of its resources is one that costs less to run, and that keeps rates down for everyone.

Have questions? Garfield Clean Energy offers free coaching on everything to do with home and business energy efficiency.

Dave Reed is communications director for CLEER (Clean Energy Economy for the Region), the nonprofit that manages the programs of Garfield Clean Energy.