What Is Time-of-Day (Flexible) Pricing for Household Electric Rates?
Time-of-Use Power Rates
With the advent of "smart" power meters, electric companies are now often capable of reading your meter from a remote location and at any time they wish, and computers make it easy for them to keep track of just when you are using power.
Large industrial users have long had the ability to have their electricity charges based on the time of day they actually use that electricity. They try to perform their high energy tasks late at night when the charge is less. With the smart meters, many electric utilities are now making that option available to the homeowner as well. It is to their advantage; if they can convince people to use power when the demand is lower, the utility will need less generating capability.
While not available everywhere by any means, the option is becoming more popular throughout the country. Often termed "Time of Day" or "Flexible Pricing" these plans are worth checking into to see if they will fit your needs and there are any savings possible. Saving electricity at home is a great goal; it can not only help you personally but the country as a whole.
Flexible Pricing for the Home
It would be impossible to discuss all the various rate schedules in use through the country here, but we can look at one utility schedule and how a similar plan might affect you in your own home. From that point, you will have to contact your own electric utility to see just what their plan is (if they have one) and how it might affect you. Some locations in Texas, for example, have free power when off-peak, but charge a fixed monthly fee in addition to usage fees to use the service.
Below is the flexible pricing schedule for Idaho Power in Boise, Id., followed by their regular schedule. The flexible schedule charges vary by season and time of day while the regular schedule varies by season and the amount used over the entire month.
Flexible Rate Schedule
Time of Day, weekdays
1 p.m.–9 p.m.
9 p.m.–1 p.m.
Time of Day, Weekdays
7 a.m.–9 p.m.
9 p.m–7 a.m.
Weekends and certain holidays are all off peak with the time of use schedule.
Now for the regular schedule:
Regular Rate Schedule
Summer Rates, July-Aug
Non Summer, Sept-May
tier 1, 0-800 kWh
tier 2, 801-2000 kWh
tier 3, over 2,000 kWh
As an example let's look at a day in November, where we'll assume the usage was 1400 kWh (Kilo Watt Hours) off-peak and 1000 kWh on peak.
The flexible pricing plan gives us 1400X7.32 + 1000X9.43 = $196.91
The regular pricing plan gives us 800X7.97 +1200X8.78 + 400X9.73 = $208.04
A savings of $11.13, or a little over $130 per year if we did the same thing each month. At the same time, though, if we had used 1400 kWh On peak and 1000 off-peak the results would have been much different. So how can we shift our usage to nighttime rather than daytime?
Making Flexible Spending Work For You
The first step will be to at least make an educated guess as to when you are using power. This writer uses an electric heat pump for heat, and that will be the biggest electric user in the house. Also to consider is the hot water tank, range, electric clothes dryer, and any other large user you have. Lighting (especially if CFL's or LED bulbs) won't matter too much for most homes, and neither will a flat-screen TV. The older TV's did matter as they pulled considerably more current, but the newer flat TV's are much more energy efficient. It's the big items that are going to matter, then, and not all the small things that use power most of the time.
Below is a graph of a single day's use for this writer, provided by the utility company:
We see a big jump at 6 a.m.—that's when the programmable thermostat installed years ago begins to heat the house up. It then turns the heat back down at 7 AM, to remain down until 11 a.m., whereupon it turns the heat on again, this time until 10 PM.
There is a surge around 11–12 noon, when the furnace comes back on and lunch is cooked. Usage then remains fairly constant until 9 p.m. when the electric car begins to charge its battery. At the same time, the dishwasher is started and, if necessary, the clothes washer and dryer are run. This task is generally saved for the off-peak hours of the weekend, but sometimes it has to be done during the week. We can also see a small jump around 5 p.m. when dinner is cooked.
As we see here, most heavy use can be shifted to evening hours and/or weekends if we wish. There are still several electric appliances that have not been well controlled—an electric baseboard heater on its own thermostat and the hot water heater come to mind—but overall there is more being used at night than in the day even with the electric furnace keeping the house warm whenever the owner is home (they are gone from 8 a.m. to 11 a.m. each day).
If you have an empty house during weekdays, then, you may be a good candidate for the time of use pricing from your utility. If, on the other hand, you are home all day and using electricity while there, it will probably cost more than it saves.
Some utilities charge a "changeover" fee that can make experimentation difficult, and most will require that a change be left alone for several months. My own utility has no fee, but requires that if I go back to the regular schedule I must leave it there for at least one year. I cannot, then, change back and forth on a whim, but have to choose and live with it for a year or more. Care is needed to make sure that any change won't cost you an arm and a leg; my utility offered a free analysis which indicated I should save about $100 per year. As the new electric car will only add to that savings (presuming I only charge at night), it was worth a try.
My own experience is that the savings are a little more than what I use to charge the car; I can thus do most of my driving for free, without buying any gas and with the electricity necessary "paid" for by making a few simple, painless changes in my work schedule at home.
© 2015 Dan Harmon