Understanding Seasonal Energy Efficiency Ratio and Heat Pumps

Understanding Seasonal Energy Efficiency Ratio and Heat Pumps

14 February 2021 |  News & Resources

Many people are hearing more about heat pumps and their efficiency these days. Since they use different types of efficiency ratings than most furnaces and boilers, it is important to understand those differences and the potential for savings.

What Is a SEER Rating?

To calculate seasonal energy efficiency ratio, experts divide the total ability of a unit in BTUs during normal use by the watt-hours of electricity required to power it. When a unit has a higher SEER number, it means that it is more efficient.

Just as purchasing a more efficient car that requires less gasoline to operate will cost less in fuel expenses over time, a heat pump that does not consume as much electricity to operate will help reduce electric costs over time. Today, many people still use furnaces or boilers that are less efficient, and many of those older heaters are powered by natural gas.

Since natural gas is slowly being phased out as an energy source for home heating, it is a good time to look toward the future and consider electric heat pumps instead of gas-powered furnaces or boilers. In addition to eliminating the worry of dangerous gas leaks, newer electric heat pumps tend to have high SEER and HSPF ratings.

Are SEER Ratings for Cooling or Heating?

SEER ratings are commonly used in advertising to show the efficiency of an air conditioner in a home. Unlike air conditioners, heat pump systems have both heating and cooling abilities. Because of this, heat pumps also have SEER ratings. Additionally, heat pump efficiency is measured by heating seasonal performance factor. Like the SEER rating, HSPF is calculated using BTU output and energy consumption in watt-hours.

What Are the Different SEER Ratings?

Recommended SEER ratings tend to raise over time. This is because household cooling and heating needs comprise a large percentage of the country's energy use. Many older systems have SEER ratings between 8 and 10. Heat pumps should have at least a 6.8 HSPF rating, and a minimum 13 SEER rating is required in Canada today for new units. However, a higher SEER rating is ideal. To be considered highly efficient, a unit should have a SEER rating of 18 or higher. Some heat pumps have ratings above 20.

To better understand the value of a new electric heat pump, it helps to understand the basic structure of SEER ratings and review some examples. Comparing the percentage in average savings to the SEER number provides a good perspective on the value that a homeowner can expect from a new heat pump system. These are the average annual energy savings and SEER ratings in comparison with a 10 rating:

  • A 13 SEER rating can save 23%.
  • A 14 SEER rating can save 28%.
  • A 15 SEER rating can save 33%.
  • A 16 SEER rating can save 37%.
  • A 17 SEER rating can save 41%.

As the numbers get higher, the savings also grow.

How Do Heat Pumps Compare for Efficiency?

To some homeowners, gas boilers are still favorable for their low maintenance demands, durability and decent efficiency. However, heat pumps have several advantages to consider. In addition to being better future investments as natural gas is eventually phased out, they tend to be environmentally friendly and are financially economical. For example, Mitsubishi mini heat pumps do not require extensive ductwork installation, providing a cost-effective solution.

Mitsubishi pumps have high SEER ratings. Some hold SEER ratings of 26. The M series pumps hold a SEER rating of 30.5, and the HSPF for these pumps is 13.5. In comparison, boilers are often rated for efficiency on how much energy they consume versus how much they waste. For example, a boiler with 96% AFUE is considered highly efficient for its product type class. AFUE is annual fuel utilization efficiency. The 96% rating means that it uses 96% of the energy it consumes and wastes 4%. Lower AFUE numbers mean lower efficiency.

As mentioned before, heat pumps function for both cooling and heating purposes in a home. However, a higher number certainly means that overall efficiency will be better. Since AFUE measures only heating efficiency using only BTUs, and SEER measures efficiency with BTUs and watt-hours, it can be difficult to make direct comparisons. A good way to determine which option is a better choice is to consider the potential savings, longevity, operating costs and installation costs.

An efficient heat pump, such as one of the Mitsubishi pumps mentioned before, is typically more expensive to install than a boiler. However, the operating costs are significantly lower, making it a better long-term investment. For example, a new 96% AFUE boiler may only save a small amount each month on heating costs for someone who currently uses a boiler rated at 80% AFUE. A new heat pump with even a 23 SEER rating can save up to 56% on energy costs for someone who currently has a unit with a 10 SEER rating.

While a 96% AFUE gas-powered unit may sound like an attractive upgrade because of the high percentage, keep in mind that many people who have a boiler often have a unit that operates at about 80% efficiency. Even with a heating unit that operates at just 60% AFUE, upgrading to 96% AFUE only saves between 37% to 40% in most cases.

Learn More About Efficient Heat Pumps in Toronto

The key idea to remember is that a higher SEER rating is better for long-term savings on energy costs. The numbers in this blog are estimates based on averages. Now is a good time to consider a new heat pump in the Toronto area. Our technicians can help you evaluate your current energy use and needs, and they can provide suggestions for better savings. Please give us a call to learn more.