In the average home, heating expenses account for 29% of annual energy costs. That means most homeowners constantly look for ways to improve their heating efficiency. The venerable natural gas furnace was the de-facto heating efficiency champion for decades. It combined fairly good efficiency with the lowest heating fuel cost. However, gas furnaces were never the most efficient heating solutions available. In reality, various electric heating systems could always claim higher energy efficiency. Today, electric heating systems are finally taking their place on top of the efficient heating market. Here’s everything you need to know.
Understanding the Heating Efficiency Status Quo
Currently, approximately 59.6% of homes in our state rely on natural gas furnaces for heat. Most of those are standard furnaces, achieving approximately 80% energy efficiency. There are also some high-efficiency models in service, and those average between 90% and 95% efficiency. While that may not sound very high, gas furnaces enjoy another advantage: cheap natural gas. The United States is the leading producer of natural gas. That keeps the fuel readily available and thus inexpensive. As a result, the average home in Missouri pays about $90 per month in natural gas costs. Even that number may be misleading, as most homes with natural gas also use it for cooking and water heating.
Electricity and Heating Efficiency
It may surprise most homeowners to know that electric heating systems have always been more efficient than gas models. Electric furnaces, for example, always operate at 100% energy efficiency. That’s because they depend on electric resistance heating elements. Those convert electricity into usable heat with no losses.
However, electric furnaces are expensive compared to natural gas. Even with perfect efficiency, running an electric furnace is costly, making them a nonviable option in our region. The good news is that electric furnaces aren’t the most efficient electric heating systems available.
The Emergence of Heat Pumps
Today, the most efficient electric heating system is a heat pump. However, heat pumps are not a new technology. Heat pumps date back to the 1850s, with early models keeping conditions habitable in salt mines. By the mid-1940s, heat pumps were already becoming common elsewhere, especially in large commercial buildings. The United States even experienced a significant uptick in adoption in the 1970s as an oil crisis drove up fuel costs.
Heat Pump Operating Basics
A heat pump is unlike any other kind of electrical heating system. Heat pumps don’t convert electricity to heat like an electric furnace does. Instead, they take advantage of the heat energy found in the outdoor air. While that may sound unusual, it makes more sense when you understand how the process works.
Heat pumps use refrigerants as a working fluid to absorb and transport heat. They do this by controlling the refrigerant’s pressure, which controls its temperature and boiling point. Generally speaking, raising the pressure of a refrigerant increases its temperature and boiling point, while lowering the pressure has the opposite effect.
To collect heat outside, a heat pump reduces its refrigerant temperature to as low as -15 degrees Fahrenheit. Once at that temperature, the refrigerant can absorb heat from any warmer substance. That includes the outdoor air, even on a cold winter day. When the refrigerant absorbs enough heat while passing through an outdoor heat exchanger, it boils. That transforms the refrigerant into a warm gas.
Next, the heat pump uses a compressor to increase the pressure of the warm refrigerant, which increases its temperature to between 110 and 140 degrees Fahrenheit. The now-hot refrigerant travels to the heat pump’s indoor unit, which houses another heat exchanger and a blower fan. The indoor unit transfers the heat into the home’s air.
How Efficient Are Heat Pumps?
A modern air-source heat pump delivers efficiency levels virtually no other heating system can. They can reach efficiencies as high as 400% in mildly cold temperatures. That blows away both gas and electric furnaces. It’s also high enough to overcome the high cost of electricity, making heat pumps financially viable anywhere.
Heat pumps are also the main component of geothermal HVAC systems. In these systems, heat is collected through an underground loop. Heat pumps achieve even higher average efficiency than air-source models. Plus, they sustain their high efficiency year-round, no matter the weather. Air-source heat pumps, by contrast, progressively lose efficiency as outdoor temperatures drop.
It’s worth pointing out that some of today’s air-source heat pumps employ advanced technology to retain their efficiency. For example, some use inverter technology and variable-speed compressors. Those let heat pumps conserve energy by scaling their capacity up or down as needed. Some also use a process known as flash injection to enhance their efficiency. That involves a secondary refrigerant loop that minimizes wasted heat energy. With those, any still-warm refrigerant gets rerouted for a second pass through the system’s indoor unit. That maximizes heat extraction while simultaneously lowering outdoor refrigerant temperatures to improve heat collection efficiency.
The Significance of Efficient Electric Heat
The emergence of heat pumps as a viable heating option isn’t only significant due to potential energy savings. It’s also important due to the technology’s impact in fighting climate change. The average gas furnace emits up to 6,400 pounds of CO2 annually. By switching to a heat pump, you can eliminate almost all of that carbon footprint. Electrical-powered heating systems only have carbon footprints stemming from electricity generation. A heat pump can cut household CO2 emissions by up to 64%, even with fossil fuel-generated electricity. When paired with renewable energy, a heat pump’s carbon footprint is essentially zero.
The environmental advantages of heat pumps are why they’re subject to various tax credits and subsidies. Right now, you can claim a federal tax credit worth up to 30% of a new heat pump’s cost. Soon, a point-of-sale rebate program will also begin in our state, using federally allocated funds. It will offer up to $8,000 off the price of a heat pump, depending on your income. Together, the programs will help make heat pumps cost-competitive with furnaces, improving adoption rates.
Local Residential Electrical Specialists
As the leading electrical services company serving the St. Louis and Kansas City area, we know energy efficiency. If you’re interested in switching to an electric heating system, we can help. Our electricians can make whatever upgrades or modifications your home’s electrical system needs to support one. We also offer complete electrical services, from repairs and rewiring to generators and smart home installations.
Potts Electric is a family-owned and -operated company that puts customers’ needs first. Customer satisfaction is our top priority on every project. Our team of electricians has extensive training and years of experience. We also offer financing options on approved credit to help you cover the cost of larger electrical projects. We are proud to be Better Business Bureau accredited with an A+ rating. For all your electrical needs in Fenton, contact our team at Potts Electric!
