By Jordyn Ederer, class of ’26 Washington University
Traditional heating and cooling mechanisms, such as HVAC units or gas furnaces, are found to be the largest direct use of fossil fuels in U.S. buildings (Leung 2018). In a recent RMI analysis, the transition to air-source heat pumps in residential buildings has resulted in a significant and immediate decrease in carbon pollution, in some states up to 93% over a 15-year lifetime (Stone 2020). In addition to drastic reductions in emissions, households using heat pumps benefit from 2x more efficiency and significantly lower-costing heating and cooling systems compared to traditional furnaces or AC units (Department of Energy 2023; Stone 2020). As evidence surrounding heat pumps becomes increasingly more corroborative, why are American households still hesitant to make the switch?
Heating, Ventilation, and Air Conditioning (HVAC) units are mechanically similar to heat pumps in the way that they cool homes. Both forms of cooling transfer heat from inside of the home to the outside, using a refrigerant (Matson 2022). However, when it comes to heating, a heat pump differs from a furnace significantly. HVACs are commonly paired with traditional furnaces, which are found in approximately 50% of American homes in 2015 (Magill 2014). Furnaces work by burning natural gas or propane to generate energy before moving through a heat exchanger. In this system, combustion gasses are transferred out of the home and into the atmosphere, where about 20% of the energy produced is lost as exhaust, meaning standard efficiency furnaces operate at around 80% efficiency (Peavey 2022).
Heat pumps have the ability to both heat and cool, which negates the need for two separate units, like an AC unit and furnace. The key difference in heating with a heat pump is the mechanism in which the heat is sourced. Instead of fossil fuel combustion or electric resistance, the heat pump moves heat through a reversal of the cooling process (Matson 2022). Because there is no combustion, there is no efficiency lost in the process, allowing heat pumps to operate at up to 400% efficiency (Crownhart 2023).
Coping with Extreme Heat
Even with AC units operating at a maximum of 80% efficiency, they are often unreliable when facing the worsening heat waves driven by climate change. In situations of extreme heat, utility corporations choose to intentionally cut power to thousands of residential homes in order to “protect the integrity of the energy system” (Wilson 2022). Our current electrical grid cannot support the increasing cooling needs as extreme heat plagues over half of the country almost daily (Cappucci 2023). In a 2021 study done by RMI comparing typical AC units (Figure 1), high-capacity AC units (Figure 2), and heat pumps (Figure 3), they found that the heat pump consistently met their setpoint temperature of 75℉, while using up to 18.6% less energy than the high-capacity AC unit (Slanger 2021). Heat pumps are efficient, reliable, and serve as a key element in confronting the current heat crisis in the United States.
Figure 1– Typical AC Unit
Source: RMI, 2021
Figure 2 – High-Capacity AC Unit
Source: RMI, 2021
Figure 3 – Heat Pump
Source: RMI, 2021
Urban heat islands disproportionately plague communities based on certain demographics, like race and income (US EPA 2019). Various studies reviewed by the EPA show that, “some communities in the United States, particularly those that are low-income and with higher populations of people of color, have neighborhoods with higher temperatures relative to adjacent neighborhoods in the same city” (US EPA 2019). In some cases, the temperature difference between communities of color and adjacent white neighborhoods is significant and deadly. The residents condemned to these heat islands through historically racist zoning practices are now forced to choose between eating or cooling (Bedayn 2023).
Although heat pumps lessen energy costs in the long run, significant up-front installation costs serve as barriers to low-income residents. These residents are facing the worst of the heat and are left to cope with little to no defense. Federal funding initiatives targeting home energy efficiency are often inaccessible for most eligible residents. Michelle Graff, Assistant Professor of Urban Affairs at Cleveland State University, finds that a mere 16% of the country’s eligible population actually accesses these funds. In order to adequately cope with the disproportionate energy burden facing these communities, federal subsidies and grants need to be made less restrictive and more accessible to those they intend to aid.
Federal Funding Attempts
As President Biden’s Administration continues to allocate billions of dollars in federal grants towards climate change mitigation, the switch to cleaner, more efficient forms of energy seems more likely than ever. In an effort to support low-income communities, the Department of Health and Human Services expanded the Low Income Home Energy Assistance Program, promoting accessibility of air conditioned public spaces (Megerian, Costley, and Daly 2023). There are a plethora of energy efficiency rebate and subsidy programs aimed at the state, industry, nonprofit, and residential levels.
At the root of the home energy efficiency dilemma is the disconnect between new technology and contractor training. When contractors are ill-equipped, untrained, and uncomfortable with installation and maintenance of newer forms of energy, installation becomes another barrier to access. In order to encourage participation from this sector, the Department of Energy has released the State-Based Home Energy Efficiency Contractor Training Grants, where states receive federal funds to finance the training, certification, and testing of residential energy efficiency and electrification contractors (Department of Energy 2023). Once contractors are aware of the mechanisms behind newer home energy sources such as heat pumps, hesitancy will turn to confidence in and advocacy for cleaner, cheaper, and more efficient home energy systems.
Traditional HVAC units and furnaces are outdated, inefficient, and unreliable. As climate change increases the demand for energy amidst higher stakes with deadly heat waves, residents face insurmountable energy costs or inability to cool their homes altogether. Standard heat pumps require less energy, provide stable temperatures year-round, and significantly lower home energy costs. In order to remove the barriers to access these resources, substantial changes need to be made at the federal level acknowledging inaccessibility of funds, disproportionate burden of heat, and a lack of capacity in the contracting sector.
Bedayn, Jesse. 2023. “Record Heat Waves Illuminate Plight of Poorest Americans Who Suffer without Air Conditioning.” AP News. https://apnews.com/article/heat-wave-low-income-race-death-air-conditioning-f897e336d6d99ee2a53024f42ad7b8b5 (July 31, 2023).
Cappucci, Matthew. 2023. “Five Things to Know about the Brutal U.S. Heat Wave.” Washington Post. https://www.washingtonpost.com/weather/2023/07/18/heat-wave-southern-us-record-temperatures/ (July 31, 2023).
Crownhart, Casey. 2023. “Everything You Need to Know about the Wild World of Heat Pumps.” MIT Technology Review. https://www.technologyreview.com/2023/02/14/1068582/everything-you-need-to-know-about-heat-pumps/ (July 26, 2023).
Megerian, Costley, and Daly. 2023. “Biden Looks to Provide Relief from Extreme Heat as Record High Temperatures Persist across the US.” AP News. https://apnews.com/article/biden-extreme-heat-climate-change-osha-d24be7fe0c7bb79bede655db10fe2e00 (July 31, 2023).