As we transition from the often-oppressive heat of an Alabama summer to the cold and sometimes frigid temperatures of an Alabama winter, it’s time to make sure your heat pump system is ready to keep your family warm.

Preparation not only includes winterizing your home, practicing energy efficiency and properly maintaining your heating unit, but it also includes bracing for the potential high bills that can come with keeping your home comfortable throughout the winter.

Many factors can impact heating costs, according to Mark Gallier, an Alabama Power HVAC trainer, who has worked at the company for 11 years.

Those factors include the size of your house, insulation, air leakage (windows and doors), large windows on the north side of your house that could impact the heating load, whether you have single- or double-pane windows, the floor over a crawl space isn’t insulated and the efficiency of the heating system, etc.

Anthony Cook is the media relations principal for Alabama Power Company.

Some of these factors are why “older homes typically take more energy to heat vs. newer homes built to current energy codes,” Gallier said.

A hidden factor that can drive up winter power bills is strip heating. On your thermostat, it might show up as “Auxiliary Heat” or “Emergency Heat.” On your bill, it shows up as expensive, potentially increasing your heating costs by hundreds of dollars above and beyond the heat pump alone.

The strip heating system is inside your heat pump. You can manually turn on Emergency Heat with the controls on your thermostat, but that should be done only when the heat pump is not functioning properly, Gallier said.

Auxiliary Heat, on the other hand, automatically engages when your heat pump needs help warming your home.

The difference between the outdoor temperatures and the indoor thermostat settings determines when your strip heating automatically kicks on. Operating outside a 1.5- to 2-degree range between the temperature and the thermostat setting will cause your strip heating to automatically engage.

For instance, if the indoor temperature is 62 degrees and you set your thermostat to 70, the strip heating will automatically engage to help your heat pump warm your home to the desired temperature. But that helping hand from the strip heating adds to your heating costs.

“Stage 1” indicates the heat pump is working on its own to raise the temperature a single degree from 68 to 69. When the unit is asked to raise the temperature two degrees — from 68 to 70 — strip heating automatically engages to assist the heat pump, indicated by “Stage 1 & 2” on the thermostat. (Anthony Cook / Alabama News Center)

To prevent the strip heating from engaging, instead set your thermostat to 63. Once your home reaches that temperature, bump the thermostat up to 64, and so on, until the thermostat reaches the desired 70 degrees.

It might be a little annoying, but it’s a lot more affordable.

However, be aware that when the temperature outside is near, at or below freezing, your heat pump might need the help of strip heating to warm your home regardless of where you set the thermostat.

This is why homeowners sometimes see heating bills rise during cold weather, even when you don’t adjust the thermostat settings.

To help customers monitor their energy use, Alabama Power offers Electronic Home Energy Reports (eHERS). This free report is generated each month to compare a customer’s home energy usage over time and provides energy insights based on usage and characteristics. The report also offers tips and recommendations for reducing energy use. For more information or to sign up, visit ehers.AlabamaPowerPrograms.com.

So, what exactly is strip heating? How does it work? Why is it more expensive?

To get some answers, I recently emailed Jim Goolsby, a training analyst at Alabama Power’s HVAC training center in Jasper who has worked at the company for 26 years. Here’s what he shared:

Jim Goolsby, a training analyst at Alabama Power’s HVAC Training Center in Jasper, demonstrates how strip heating works. (Anthony Cook / Alabama News Center)

What is strip heating?

Goolsby: Strip heating is electric resistance coils that provide additional heat to a heat pump (similar operation to a space heater).

How long has that technology been around?

Goolsby: Since the 1800s … but more specifically, it’s been installed in heat pumps since the 1970s.

How does it work?

Goolsby: Electricity is delivered to a coil of highly resistant materials (typically nichrome) that becomes red hot and produces heat.

Do all heat pumps have them?

Goolsby: Not necessarily. … A large majority of heat pumps do have them, but there are some models that use a gas furnace as the auxiliary heat source. Some high-efficiency units that utilize variable refrigerant flow technology don’t require auxiliary heat.

What are the advantages of a heat pump that doesn’t have heat strips?

Goolsby: The simple answer is higher efficiency. However, the heat pumps that don’t require auxiliary heat already operate at a much higher level of efficiency.

Walter Lawson has worked with Coolray Heating and Air for seven years and trained recently at the HVAC Training Center in Jasper. The best way to make sure your unit is working as efficiently as possible is to have it checked by a professional like Lawson once or twice a year. (Anthony Cook / Alabama News Center)

When the temperature is below 32 degrees, how difficult is it for a heat pump to heat your home without heat strips?

Goolsby: Not all heat pumps are created equal. Performance levels and heating capacities can vary depending on the efficiency rating of each system. All heat pump systems have a “thermal balance point.” This is the calculation of BTU output and heating efficiency and capacity.

Are there different sizes or wattages of heat strips?

Goolsby: Yes, most heater kits are available in increments of 5 kw. Each heat pump requires a different size heater kit based on the size or capacity of the system. For example, a 2-ton system would usually have a 5-kw heater. A 3-ton system would potentially have a 10-kw heater kit. And a 4- or 5-ton system would likely have a 15-kw heater. (These are all estimated applications.)

Why does using strip heating make such a difference on your power bill?

Goolsby: The heat strip is significantly less efficient than the heat pump! The resistance heating element consumes approximately three or four times the energy that a heat pump consumes to produce the same amount of heating capacity.

How can customers mitigate the impact of strip heating on their bill?

Goolsby: Improving the energy efficiency of the structure (home) will always reduce energy consumption! The other way to reduce the use of auxiliary heat is to keep your system running at peak performance by properly maintaining the system.

To learn more about how to save energy and money this fall and winter, including tips and other helpful resources, visit the Alabama Power website at AlabamaPower.com/Winterize and AlabamaPower.com/WinterBill.

Between the Lines is a monthly column by Alabama Power’s Anthony Cook, sharing energy education that powers our daily lives.