A heat pump can be 100% more efficient. Yes indeed – here’s how

When you’re trying to lower your utility bills, you may be tempted to use a thermostat.

This is a good instinct. Adjust your thermostat strategically They can help reduce heating or cooling costs, but they’re not the only way to spend less on energy. There’s a big variable built into the HVAC system itself: energy efficiency.

“An efficient solution allows you to achieve the same result with less input,” he explains. Christy PedutoTrane and American Standard residential duct equipment portfolio manager.

One of the most efficient heating and cooling solutions on the market these days is a heat pump. In some circumstances, these units can actually reach over 100% efficiency – usually in the 200% to 400% range – allowing you to receive more power than you initially put in.

Here’s how it works, and why heat pumps are an effective way to heat and cool your home.

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What is energy efficiency?

Energy efficiency is a way to measure the relationship between how much energy you put into a system and how much you get out of it.

Let’s say you pay for a certain amount of gas to run a furnace in your home. When the system converts this gas into heat for your home, by burning it and then transferring the heat through ducts or radiators, some of it is lost along the way, essentially wasted. So, the more heat you get from this gas unit without losing it, the higher your furnace’s efficiency rating will be.

“Simply put, the more efficient we are with the energy we consume, the less energy we need” to heat the same home, Peduto says.

What is the typical energy efficiency of a fossil fuel heating system?

Traditional fossil fuel heating systems can have a range of efficiency ratings, depending on the age of the equipment and your home’s setup.

A typical gas oven, for example, usually has… Efficiency between 80% and 98%. Peduto says 80% is the minimum efficiency rating now required for furnaces sold in the United States, a threshold Which will jump to 95% In 2028.

But this rating can be pushed down in two ways.

For example, if heat from the furnace is forced through the air ducts, the air may lose heat as it travels to the heater vent. That depends Gwendolyn van der Lindena lead algorithm engineer at a San Francisco heat pump startup Quilt. The electricity used to operate fans or blowers is not included in standard gas furnace efficiency calculations, Peduto says.

feature	Fossil fuel heating system (gas furnace)	Electric heat pump
Measure efficiency	Annual Fuel Utilization Efficiency (AFUE)	Coefficient of performance (COP)
Typical efficiency range	80% to 98% (AFUE)	100% to 400% (COP 2 to 4)
mechanism	Heat is generated by burning gas	It transfers heat from one place to another (extracts heat from the outside air).
Why can it exceed 100%?	Its efficiency cannot exceed 100% because it generates heat	It moves energy rather than creating it, requiring less electrical energy input than thermal energy delivered.
Minimum efficiency (US)	80% (minimum required for new ovens, scheduled to rise to 95% in 2028)	Older models can provide a COP of 2 (at 200% efficiency). Ministry of Energy States that the minimum for newer models is 3.1 COP
Efficiency warnings	Efficiency rating can be lower due to heat loss in ductwork or electricity used for fans/blowers	Efficiency can decrease at very cold temperatures (COP efficiency can drop below 1/100%). Newer models are better at maintaining efficiency

What is the typical efficiency of an electric heat pump?

When we discuss the efficiency of electric heat pumps, we can use an analogy known as “Performance coefficient“, or COP. This measures the amount of electricity required to operate the system compared to the amount of energy (heat or cooling) being delivered to your home.

Even an older heat pump may have a COP of two, meaning it transfers twice as much energy to your home as it does to operate. “It’s amazing what it can do,” Peduto says.

But newer heat pump systems can go even higher, van der Linden says. Her company model Average COP of fourBasically, 400% efficiency.

However, at some extremely cold temperatures, the COP of the heat pump It can actually go down to less than oneWhich means they are less than 100% efficient and consume more energy to operate than they ultimately transmit into your home. Newer heat pumps can maintain efficiency at lower temperatures. Quilt pattern, for example, COP reports of two At 5 degrees Fahrenheit.

How can the efficiency even exceed 100%?

The answer lies in the fundamental innovation of heat pumps. They do not generate heat like a furnace by burning gas. Instead, simply heat pumps It moves temperature from one place to another.

In the winter, a heat pump extracts heat from the outside air (yes, there is… some The heat is there even in the dead of winter) and the refrigerant is used to extract that energy and blow it into your home as hot air. As Peduto explains, “You’re not producing heat, you’re capturing it from the outside and moving it inside.”

This allows heat pumps to have higher efficiency ratings: it often takes less energy to move heat than to generate heat.

However, the efficiency of a heat pump varies depending on the outside temperature. If there is a large difference between the desired indoor temperature and the current outdoor temperature (on a very cold winter day, for example), the heat pump will have to work harder to extract heat from the outside air, and its efficiency will be reduced to a minimum.

But the opposite is also true. If it’s a mild winter day, there’s more heat energy floating outside, which means your heat pump won’t be working as hard to extract it.

Why is energy efficiency important to you?

Most consumers will care about efficiency for a simple reason: it can lower their utility bills. The more efficient your HVAC system is, the less energy you’ll need (to pay for) to keep your home at a comfortable temperature.

However, switching from a gas-powered system to an electric heat pump system (even with its high efficiency) will not work. always Saves you money. If you live in a state where gas prices are better than electricity prices, or where you have many very cold winter days, it may be cheaper for you to run a gas furnace.

Of course, price isn’t the only reason to switch. Burning less fossil fuels is good for the environment and can help reduce greenhouse gas emissions, even if it doesn’t immediately help your wallet.