TL;DR
Get backup power and energy gear delivered free with Prime
- Fast, free delivery on millions of items
- Prime Video, Amazon Music and more included
- Member-only deals all year
An RMI study says adding heat pumps in states with spare winter grid capacity could spread fixed grid costs across more electricity use, potentially lowering residential rates. Its estimates are directional, not forecasts, and lower rates do not guarantee lower bills for households switching from gas.
A new study from clean-energy think tank RMI finds that adding heat pumps in states with unused winter grid capacity could spread fixed electricity-system costs across more usage and potentially lower residential electricity rates. The analysis covers 24 states and Washington, D.C., but its savings figures are directional estimates, not predictions of what utilities or households will pay.
Electric grids are generally built to meet periods of peak demand, which in much of the country occur on hot summer afternoons. RMI’s analysis finds that roughly half of U.S. states have spare capacity in winter. In those places, heat pumps could add electricity use during lower-demand periods without necessarily requiring costly new grid infrastructure. The study also reasons that heat pumps used for cooling would largely replace less efficient air conditioners, rather than adding equivalent new summer demand.
Electricity rates pay for both the energy consumed and fixed system costs, including poles, wires, power plants and transformers. RMI says that when more electricity is used across existing infrastructure, those fixed costs can be spread over more kilowatt-hours. Under the study’s scenario of maximizing heat pump deployment without expanding the grid, residential rates could average 13% lower than they otherwise would be, accounting for inflation. The report equates that average rate difference to about $200 per customer annually.
The potential varies by state, as it does for heat pump adoption. RMI estimates that Michigan could accommodate 3.6 million home heat pumps and see residential rates fall by as much as 27%. The study also finds that hybrid systems—heat pumps paired with existing fossil-fuel furnaces or boilers for the coldest periods—could allow more homes to adopt heat pumps within available grid capacity. In Illinois, the analysis says only 30% of households could have a heat pump as their sole heating appliance within the studied headroom; its modeled optimal mix was 79% hybrid systems and 21% all-electric heat pump systems.
How More Use Could Lower Rates
The findings challenge the broad argument that widespread heat pump adoption must strain the grid and force major upgrades everywhere. In states with winter headroom, additional electricity use could make existing infrastructure work harder without adding a matching peak, while spreading its fixed costs across more consumption. That could affect residential rates for customers beyond heat pump adopters, according to the study’s analysis.
The distinction between rates and bills matters. A lower price per kilowatt-hour does not automatically mean that a household will spend less overall. A home’s total bill depends on how much energy it uses, the efficiency of its equipment and insulation, the fuel it replaces, and the local prices of electricity and gas. RMI did not estimate the bill changes for households switching to heat pumps, so the study is not a guarantee of household savings.
The hybrid-system finding also offers a possible near-term route to emissions reductions in places where a heat pump alone could push winter demand beyond available capacity. Keeping a furnace or boiler for the coldest hours could limit peak electricity needs while allowing a heat pump to handle much of the heating season. RMI says this approach could support more installations within the grid’s existing headroom; it does not mean every home or state has the same capacity or economics.
Products Worth Considering
Philips Hue Bridge Pro Smart Lighting Hub
Samsung 42-Inch Class OLED S90F 4K Smart TV (2025)
Bose TV Speaker (2nd Gen) Compact Soundbar with Bluetooth and HDMI-ARC, Black
As an affiliate, we earn on qualifying purchases.
Winter Headroom and Hybrid Systems
Heat pumps provide heating and cooling by moving heat rather than generating it through combustion. Their electricity use can rise during cold weather, and some installations use electric-resistance backup strips when the unit cannot meet demand. Those strips can consume substantially more electricity, a factor relevant to the grid-capacity question examined by RMI.
The study’s central comparison is seasonal: peak electricity demand often arrives in summer, while winter demand is lower in many states. That pattern leaves capacity that may be used by heat pumps, though the amount differs across regions. RMI’s estimates apply to the 24 states and Washington, D.C. it analyzed, not automatically to every utility or household. Study co-author Ryan Shea described the grid as an underused resource during lower-demand periods, using a toll bridge with too few users as an analogy for fixed costs spread across customers.
RMI’s proposed hybrid mix reflects the limits of relying on grid-wide averages. In some places, a heat pump operating alone—particularly with resistance backup—could use more of the available winter capacity than a heat pump paired with a fossil-fuel system for extreme cold. The study says more installations, including hybrid systems, could still cut emissions compared with having fewer heat pumps, but the emissions and cost outcomes depend on local conditions.
“The larger the reduction in electricity rates, the higher likelihood that someone’s energy bill will decrease with a heat pump.”
— Ryan Shea, RMI study co-author
What the Estimates Cannot Show
RMI did not have access to utility-specific data that could refine its results. The reported rate reductions are directional estimates, not forecasts, and the analysis does not establish that a particular utility will lower rates or avoid grid investment. Local peak demand, equipment choices and utility costs may alter the results.
The study also did not calculate how much individual households would pay after switching to a heat pump. University of Michigan researcher Parth Vaishnav pointed to a 2024 Michigan study he co-authored, which found that switching from gas to a heat pump could raise annual bills for some households by more than $1,000 under the fuel prices then in effect. That finding is specific to its study conditions; it does not settle the costs for other homes or current prices.
Whether a household saves depends on what system it replaces, home insulation, heat pump efficiency, heating demand and the relative prices of gas and electricity. The source material also does not specify when RMI’s analysis was published or provide utility-by-utility outcomes, limiting the ability to assess how quickly the modeled rate effects might appear.
Local Data Will Shape Outcomes
The next step for evaluating the study’s estimates is to compare them with utility-specific capacity, peak-demand and cost data. RMI says such information would refine the state-level results; the source material does not identify a utility review, policy decision or implementation schedule that is already underway.
Policymakers could use the analysis to consider incentives for heat pumps, including hybrid systems, in places with spare winter capacity. Any such decisions would still need to account for local grid conditions and household economics. For consumers, the study points to potential system-wide rate effects, but it does not provide a personal bill estimate: that requires comparing a home’s current heating costs, electricity and fuel prices, equipment performance and expected energy use.
Key Questions
What did the RMI study find about heat pumps and electricity rates?
RMI found that in 24 states and Washington, D.C., heat pumps could make use of spare winter grid capacity and spread fixed system costs over more electricity use. Its modeled scenario estimated average residential rates could be 13% lower than they otherwise would be, but that is a directional estimate, not a forecast.
Does a lower electricity rate mean a heat pump will lower my bill?
No. A lower rate is a lower price per kilowatt-hour; a household’s total bill also depends on how much energy it uses and the cost of the fuel it is replacing. RMI did not estimate individual household bill changes.
Why might a hybrid heat pump use less grid capacity?
A hybrid system keeps a gas or other fossil-fuel furnace or boiler for the coldest periods, so the heat pump need not meet all heating demand at times of high need. RMI’s analysis says this could allow more homes to install heat pumps within existing grid headroom.
Are the estimated savings certain for every state or utility?
No. The study’s estimates are directional, and RMI lacked utility-specific data to refine them. Available winter capacity and potential rate effects differ by place, so the reported state-level results should not be treated as guaranteed outcomes for a particular utility or customer.
Source: canarymedia.com
