Heat Pump Efficiency: How to Understand It and Lower Your Energy Bill

When homeowners start researching new heating systems, one term comes up again and again: heat pump efficiency. It sounds technical, but understanding it does not have to be complicated. In fact, learning how heat pump efficiency works can help you choose the right system, stay comfortable year-round, and keep your energy bill under control.

Heat pumps are considered one of the most energy-efficient options for both heating and cooling. The reason is simple. Instead of generating heat the way a furnace does, a heat pump moves heat from one place to another. That difference has a major impact on energy use, operating costs, and long-term savings.

This guide explains how heat pump efficiency is measured, what the ratings really mean, and how to choose a highly efficient system that fits your home.

How Heat Pumps Work and Why Efficiency Matters

To understand heat pump efficiency, it helps to understand how a heat pump works.

Traditional heating systems generate heat by burning fuel or by using electric resistance heating. Electric resistance systems turn electricity directly into heat, which is reliable but not very efficient.

A heat pump works differently. It transfers heat rather than creating it. During winter, it pulls heat from the outdoor air or the ground and moves it inside. During summer, it removes heat from inside your home and sends it outdoors. Because moving heat requires less energy than generating it, heat pumps can deliver more usable heat than the electricity they consume.

This is why heat pumps are widely recognized by organizations like the Department of Energy as a high-efficiency solution for space heating and cooling.

The Most Important Heat Pump Efficiency Ratings

Heat pump efficiency is measured using standardized ratings that allow homeowners to compare systems fairly. The two most important ratings are HSPF and SEER.

Heating Seasonal Performance Factor (HSPF)

HSPF stands for Heating Seasonal Performance Factor. It measures how efficiently a heat pump provides heat over an entire heating season.

HSPF is calculated by dividing the total amount of heat produced during the season by the total electricity used. The higher the HSPF number, the more heat you get for each unit of electricity.

For perspective:

• Older or less efficient systems may have an HSPF of around 6 or 7
• Modern high-efficiency heat pumps often have HSPF ratings of 8 to 10 or higher
• Electric resistance heating has a much lower efficiency by comparison

A higher HSPF usually leads to a lower winter energy bill, especially in regions where heating is used frequently.

Seasonal Energy Efficiency Ratio (SEER)

SEER stands for Seasonal Energy Efficiency Ratio. This rating measures cooling efficiency instead of heating efficiency.

SEER works similarly to HSPF but applies to air conditioning performance. It reflects how efficiently the system removes heat from your home during the cooling season.

Since heat pumps provide both heating and cooling, SEER and HSPF together give a complete picture of year-round efficiency.

Other Efficiency Terms You May See

Energy Efficiency Ratio (EER)

EER measures cooling efficiency at a specific outdoor temperature rather than across an entire season. While SEER is usually more useful for homeowners, EER can offer insight into performance during very hot conditions.

Coefficient of Performance (COP)

COP compares how much heat a system delivers to how much electricity it uses at a given moment. Higher COP values indicate better efficiency. COP is more common in technical discussions, but helps explain why heat pumps can outperform electric resistance heating.

Types of Heat Pumps and Their Efficiency

Different types of heat pumps achieve efficiency in different ways. Choosing the right type matters just as much as choosing the right rating.

Air Source Heat Pumps

Air source heat pumps transfer heat between your home and the outdoor air. They are the most common option and typically the most affordable. Advances in technology have made modern air source heat pumps much more effective in colder weather than older models.

Ground Source Heat Pumps

Ground source heat pumps, also called geothermal systems, pull heat from the earth rather than the air. Because ground temperatures are more stable year-round, these systems can achieve very high efficiency. They usually cost more to install but can deliver long-term energy savings.

How Heat Pump Efficiency Affects Your Energy Bill

Heat pump efficiency has a direct impact on how much you pay for heating and cooling.

A system with a higher HSPF uses less electricity to produce the same amount of heat. That means lower operating costs during the heating season. A higher SEER reduces cooling costs in summer.

Actual savings depend on several factors:

• Climate and outdoor temperatures
• Home insulation and air sealing
• Thermostat settings and usage habits
• Proper system sizing and installation

A highly efficient heat pump that is poorly sized or installed incorrectly may not deliver the savings you expect. Professional evaluation is essential.

Cold Weather Performance and Backup Heating

In very cold conditions, some air source heat pumps rely on electric resistance heating as a backup. Electric resistance heating is reliable but less efficient, which can increase energy use during extreme cold.

Cold climate heat pumps and ground source systems are designed to reduce reliance on backup heating. If you live in an area with long or harsh winters, this is an important consideration when evaluating heat pump efficiency.

Choosing the Right Efficiency Level for Your Home

Higher efficiency systems typically cost more upfront, but they often save money over time through reduced energy bills. The right balance depends on your climate, budget, and how long you plan to stay in your home.

An HVAC professional can perform a load calculation, review your home’s insulation, and recommend a system that matches your heating and cooling needs without overspending on unnecessary capacity.

Final Thoughts on Heat Pump Efficiency

Heat pump efficiency is about more than just a number on a label. It reflects how effectively a system transfers heat, how much electricity it uses, and how it performs in real-world conditions.

By understanding HSPF, SEER, and the different types of heat pumps available, you can make a confident decision that supports comfort, reliability, and long-term energy savings.

Frequently Asked Questions

What is heat pump efficiency?

Heat pump efficiency measures how effectively a heat pump transfers heat using electricity. Higher efficiency means more heating or cooling output for less energy input.

What is a good HSPF rating?

Most modern systems have an HSPF of 8 or higher. Higher ratings generally indicate better heating efficiency and lower energy costs.

Is a higher efficiency heat pump worth the cost?

In many cases, yes. While high-efficiency systems cost more upfront, they often reduce energy bills enough to offset the initial investment over time.

Do heat pumps work in cold climates?

Yes. Modern cold-climate heat pumps and ground-source systems are designed to perform efficiently even in low temperatures.

What matters more, SEER or HSPF?

SEER is more important for cooling-focused climates, while HSPF matters more in areas with longer heating seasons.

Editor’s note: Our team of experts is always on the lookout to bring you the most up-to-date and comprehensive information about our industry. This post was originally published in January  2024 and has been updated to reflect current best practices.