How does cold weather affect your bill?

It takes more energy to heat your home when the temperature drops.

The more difference there is between the temperature outside and the thermostat setting inside, the harder your heating system will work and the more energy it will use, even if you don’t turn the thermostat higher.

This is especially true for homes that don’t have enough insulation, homes with single-paned or aluminum-framed windows, and homes with a lot of air leaks around windows, doors, and plumbing & electrical boxes.

Ways to minimize your energy use during a cold snap: 

  1. Turn your thermostat down a few degrees. Each degree you lower it can save up to 2% on your heating bill. Set it even lower when you are away or asleep but be sure to keep your house at least 55 degrees at all times to prevent pipes from freezing and to avoid moisture problems.
  2. Use portable space heaters wisely. If you spend most of your time in one or two rooms, using space heaters to keep those rooms warmer, and turning your furnace down to let the rest of the house stay cooler, can help save energy. This works best if you can close off the rooms you are using, and if you only use one or two space heaters. A typical space heater uses 1,500 watts of electricity and an electric furnace uses 10 times that much. Read more about using space heaters efficiently.
  3. Get rid of drafts. If you feel cold air coming in, warm air is escaping. Keep windows and doors closed, and use caulk or weather stripping to seal leaks around windows, doors, and plumbing penetrations.
  4. Cover your windows. Tight fitting, insulated window coverings can help minimize heat loss through the windows. Keep curtains and blinds closed unless the sun is shining directly on the glass.
  5. Check your furnace filters to see if they need to be cleaned or replaced. Dirty or clogged filters make your furnace work harder, increasing energy usage.

  6. Check your insulation levels. If your home is poorly insulated, adding insulation will lower your energy bills. If you heat with electricity, ask us about rebates for insulation upgrades.
  7. Upgrade your heating system. If you heat your home with electric resistant heat (electric furnace, baseboards, plug-in heaters, etc.), consider upgrading to a much more efficient heat pump or ductless heat pump.

See More Tips for Saving Energy in Winter

Discover free and low-cost ways to reduce your energy use and cut your bill during winter months.

Learn answers to some common questions about winter electric bills.

Two ways to compare temperatures: Average temperature & degree days

Average temperature:

If your energy use is higher than you expect, it might be weather-related. Comparing the average temperature during the month to the same month last year is one quick way to tell if the increase is weather-related.

You can calculate the average temperature for your specific billing period on Weather Underground.

Month Average
Temperature
Average Temp for
Same month last year 
10-Year Average
for the Month
Mar 2021 45 44 46
Feb 2021 41 41 42
Jan 2021 44 43 40
Dec 2020 41 42 39
Nov 2020 46 44 45
Oct 2020 55 49 54
Sep 2020 64 61 63
Aug 2020 68 72 70
Jul 2020 68 71 68
Jun 2020 62 66 63
May 2020 58 62 58
Apr 2020 54 55 51
Mar 2020 44 47 46
Feb 2020 41 38 41
Jan 2020 43 43 40
Dec 2019 42 43 39
Nov 2019 44 46 45
Oct 2019 49 54 53
Sep 2019 61 61 62
Aug 2019 72 69 69
Jul 2019 71 70 68
Jun 2019 66 62 62
May 2019 62 60 57
Apr 2019 55 51 51
Mar 2019 47 44 46
Feb 2019 38 40 42
Jan 2019 43 44 40

For example, the average temperature during January 2018 was 44 degrees, which is 11 degrees warmer than the average of 33 degrees in January 2017. This is likely to have resulted in lower energy usage for you in January 2018 than in January 2017.

Degree days:

For a more precise look at how temperature affects your bill, you should use degree days.

A Degree Day (DD) is the difference between the average temperature for a day and 65 degrees Fahrenheit. If the difference is positive (if it’s warmer than 65), it’s called a Cooling Degree Day. If the difference is negative (if it’s cooler than 65), it’s a Heating Degree Day.

In our area, we have more Heating Degree Days than Cooling Degree Days because the average temperature is below 65 more often than it is above 65.

Here’s an example: On February 12, 2021, the average temperature in Scappoose was 26 degrees. Taking 65 and subtracting 26, we get 39, so that day had 39 Heating Degree Days.

If you know the degree days in a month, you can compare it to other months to get a feel for how much warmer or colder it was. During months with a large number of heating degree days, you can expect your heating bills to be higher. 

Month Average
Temperature
Heating
Degree Days
Cooling
Degree Days
Mar 2021 45 636 0
Feb 2021 41 856 0
Jan 2021 44 637 0
Dec 2020 41 745 0
Nov 2020 46 634 0
Oct 2020 55 317 0
Sep 2020 64 90 67
Aug 2020 68 15 122
Jul 2020 68 25 123
Jun 2020 62 197 35
May 2020 58 250 25
Apr 2020 54 336 0
Mar 2020 44 658 0
Feb 2020 41 699 0
Jan 2020 43 650 0
Dec 2019 42 730 0
Nov 2019 44 599 0
Oct 2019 49 476 0
Sep 2019 61 126 38
Aug 2019 72 4 152
Jul 2019 71 3 176
Jun 2019 66 107 36
May 2019 62 109 28
Apr 2019 55 312 0
Mar 2019 47 562 0
Feb 2019 38 732 0
Jan 2019 43 682 0

We’re here to help

If your bill is unexpectedly high, give us a call at (503) 397-0590 to discuss it. We can review your energy usage patterns and talk with you about payment arrangements that you might qualify for. We can also help you figure out if a home weatherization evaluation would be a good step to take.