You’re out of free articles.
Log in
To continue reading, log in to your account.
Create a Free Account
To unlock more free articles, please create a free account.
Sign In or Create an Account.
By continuing, you agree to the Terms of Service and acknowledge our Privacy Policy
Welcome to Heatmap
Thank you for registering with Heatmap. Climate change is one of the greatest challenges of our lives, a force reshaping our economy, our politics, and our culture. We hope to be your trusted, friendly, and insightful guide to that transformation. Please enjoy your free articles. You can check your profile here .
subscribe to get Unlimited access
Offer for a Heatmap News Unlimited Access subscription; please note that your subscription will renew automatically unless you cancel prior to renewal. Cancellation takes effect at the end of your current billing period. We will let you know in advance of any price changes. Taxes may apply. Offer terms are subject to change.
Subscribe to get unlimited Access
Hey, you are out of free articles but you are only a few clicks away from full access. Subscribe below and take advantage of our introductory offer.
subscribe to get Unlimited access
Offer for a Heatmap News Unlimited Access subscription; please note that your subscription will renew automatically unless you cancel prior to renewal. Cancellation takes effect at the end of your current billing period. We will let you know in advance of any price changes. Taxes may apply. Offer terms are subject to change.
Create Your Account
Please Enter Your Password
Forgot your password?
Please enter the email address you use for your account so we can send you a link to reset your password:
Five findings from an extremely thorough study by the National Renewable Energy Lab.
Some Americans install heat pumps because they care about climate change. But most people aren’t going to make the switch until it makes sense economically. Pinpointing where and for whom heat pumps are a good investment is surprisingly tricky because U.S. housing is so diverse, with a wide range of building sizes and ages, situated in different local climates with different utility rates.
But for the first time, researchers at the National Renewable Energy Lab have sorted through much of this complexity to get deeper to the truth about the costs, benefits, and challenges of deploying heat pumps in the U.S.
Ultimately, they found that heat pumps are a cost-effective choice in roughly 65 million U.S. homes, or about 60% of the country — and that’s before taking into account available subsidies. But there are substantial economic barriers to widespread adoption.
It’s hard to overstate how detailed the study is. The authors started with a model of 550,000 statistically representative households — basically housing archetypes that typify different combinations of building size, age, occupancy level, local climate, heating usage patterns, and existing heating systems. Each one represents about 242 real-world households. Then the authors looked at how switching to a heat pump would affect greenhouse gas emissions and energy bills across all of these different homes in a wide range of scenarios. They considered heat pumps with lower and higher efficiency ratings, and whether or not the building owner pursued insulation upgrades. They looked at different scenarios for how quickly the grid would decarbonize, how sensitive the results were to energy prices, and how subsidies from the Inflation Reduction Act affect the economics.
The paper has many interesting findings beyond the top-line result. Here are five things that stood out.
Eric Wilson, a senior research engineer at NREL and the study’s lead author, told me one of his motivations was to try to settle the question of whether heat pumps reduce emissions.
“I see a lot of people saying, well, the grid is still dirty in this state, and maybe it makes sense to wait five years to put in a heat pump because it could increase emissions,” he said.
But he found that in each of the 48 contiguous U.S. states, switching to a heat pump reduces emissions today, even if that heat pump is one of the cheaper, less-efficient models. Heat pumps are just so much more efficient than other options that they still reduce emissions despite today’s relatively dirty grid.
On average, each home could cut between 2.5 to 4.4 tons of carbon over the approximately 16 years the equipment lasts, meaning widespread adoption could result in a 5% to 9% drop in national economy-wide emissions. The effect is much more pronounced in some states, like those in the Northeast, where a lot of homes currently use fossil fuels for heating. A household in Maine that installs a high efficiency model, combined with completing insulation upgrades, would reduce emissions by an average of 11 tons per year — or about the equivalent of taking two cars off the road for a year.
The study breaks down the costs of switching to a heat pump in a few different ways.
First, there’s the up-front costs of upgrading to a heat pump, which are relatively high. A lower-rated, less efficient heat pump system may be a cheaper option than a new furnace or boiler for about 43% of households. But a higher-performing heat pump is almost always more expensive, costing an extra $8,000 to $13,000 before government subsidies (more on them later). That alone might keep heat pumps out of reach for many households.
Next, there's the potential for bill savings — which is significant. Using state average electricity and gas rates in the winter of 2021 to 2022, the study found that 86% of households can save money on their utility bills by switching to a medium-efficiency heat pump, and a whopping 95% of households will see their bills go down if they install the highest efficiency system.
So in theory, if homeowners do have the extra cash to put down, there’s a chance they could make up for high up-front costs in bill savings over time. But how good a chance?
Putting this all together, the authors looked at what percentage of households that upgraded to heat pumps would see a positive cash flow, calculated as the “net present value,” from the initial investment. Here, the results were less rosy. In many cases, high up-front costs cancel out potential savings. For example, despite the near-certain bill savings from buying one of the most efficient heat pump models, only 21% of households would see an overall economic benefit from the switch.
Still, more than half of all homes would see a positive cash flow by switching to a cheaper, minimum-efficiency heat pump.
Distribution of energy bill savings, upgrade costs, and unsubsidized net present value, relative to a reference equipment replacement scenario, using energy prices from winter 2021 to 2022 Courtesy NREL / Wilson et al., Heat pumps for all? Distributions of the costs and benefits of residential air-source heat pumps in the United States, Joule (2024), https://doi.org/10.1016/j.joule.2024.01.022
These findings underscore the importance of bringing down the cost of more efficient heat pump models, which are out of reach for many Americans but can provide significant energy bill savings. The authors suggest that policymakers can help by deploying incentives more strategically and pursuing research on “lower-cost, higher performance, and easier to install equipment.” There also may be opportunities for bulk purchasing and aggregating installations across an apartment building or neighborhood.
When it comes to bill savings, the study found that those who have systems that run on propane, fuel oil, or electric resistance heaters will pretty much always lower their bills by switching to a heat pump, no matter how efficient it is. But those who use natural gas are far more likely to lower their bills if they can afford to switch to one of the pricier, better-performing heat pumps — which cuts into the value proposition.
The following maps show the percentage of homes in each state that would see a positive cash flow from switching to a heat pump, looking at those switching from natural gas, electric resistance, or fuel oil and propane, illustrating how the value proposition is most challenging for those using natural gas.
Percentage of homes that currently have air conditioning that will see a positive cash flow from switching to a heat pump from natural gas, electricity, and fuel oil and propane. Courtesy NREL / Wilson et al. 2024
The authors also note that fixed charges on natural gas bills can play a significant role in the economics of switching to a heat pump. Most natural gas utilities charge customers a fixed amount each month, regardless of how much gas they use. If a homeowner switches to heat pumps but continues using gas for cooking, they’ll still have to pay the full fee, which can be as high as $34 a month, whereas homes that fully electrify can avoid these fees.
The results I described in the previous two sections include homes both with and without existing air conditioning systems of some kind. (With the exception of the maps, which only consider homes that have air conditioning already.)
But since heat pumps provide both heating and cooling, the economics are actually quite different for those households who already have air conditioners versus those who don't. If a household already has A/C, heat pumps appear more favorable, because a family would be able to replace two systems — an air conditioner and a furnace — with just one. If there is no pre-existing air conditioner, the heat pump will not only have higher up-front costs, but it’s more likely to increase energy bills, since the family might start using the heat pump for cooling in addition to heating.
Here are the same maps included in the previous section, but looking just at homes that do not have air conditioning.
Percentage of homes that do not have air conditioning that will see a positive cash flow from switching to a heat pump. The first column is homes that currently use natural gas, the second column is those that us electricity, and the third is those that use fuel oil and propane. Courtesy NREL / Wilson et al. 2024
There are basically zero cases where a house with natural gas heating, and no A/C, will save by switching to a heat pump. However, that result doesn’t take into account the benefits of getting air conditioning for the first time.
“They didn't include the new value that someone has, especially in a warming world and a world with more heat waves, of now having an air conditioner in your home,” Kevin Kircher, an assistant professor of mechanical engineering at Purdue University, told me. “So if you add that in, I think the economics look better.”
None of the results in the previous sections take into account the various subsidies that states and the federal government offer for heat pumps. For example, the Inflation Reduction Act included a $2,000 tax credit for heat pumps and an additional $11,500 in rebates for low- and moderate-income households. Both will increase the percentage of households for whom the investment will pencil out.
The study also doesn’t take into account the potential for homes to use smart controls that optimize their systems, or the opportunity for households to participate in demand response programs which will pay them to turn down their thermostats by a few degrees when the grid is taxed. Kircher, the Purdue professor, recently published a study of a real-world house in a cold climate where smart controls reduced heating energy costs by 23-34%.
Finally, one big takeaway from the study was that the results are very sensitive to the price ratio between natural gas rates and electricity rates, and there are reasons to believe that may become more favorable. For example, as more renewable energy is deployed, electricity could become more affordable. Meanwhile, if the U.S. increases exports of liquified natural gas, the cost of domestic natural gas could go up. The study cites a 2022 survey of oil and gas executives which found that 69% expect ‘‘the age of inexpensive U.S. natural gas to end by year-end 2025.”
“Big modeling like this entails a lot of assumptions about the future that are really hard to pin down with any real precision,” said Kircher. “But I think there's cause for optimism there.”
Log in
To continue reading, log in to your account.
Create a Free Account
To unlock more free articles, please create a free account.
Whichever way you cut it, this has been an absolute banner year for nuclear deals in the U.S. It doesn’t much matter the metric — the amount of venture funding flowing to nuclear startups, the number of announcements regarding planned reactor restarts and upgrades, gigawatts of new construction added to the pipeline — it’s basically all peaking. Stock prices are up across all major publicly traded nuclear companies this year, in some cases by over 100%.
“This year is by far the biggest year in terms of nuclear deals that has occurred, probably, since the 70s,” Adam Stein, the director of nuclear innovation at The Breakthrough Institute, told me. “It’s spanning the gamut from bringing a 40-year-old reactor back to things that have not even been proven scientifically yet.”
To name just a few announcements from this year: planning for a 4.4-gigawatt nuclear power complex is now underway in Texas; South Carolina’s state-owned utility is seeking buyers to restart construction on two partially built AP1000 reactors; New York governor Kathy Hochul is looking to build a new reactor in upstate New York; The Tennessee Valley Authority submitted a construction permit for a small modular reactor; Google signed a power purchase agreement with Commonwealth Fusion Systems; and another fusion company, Helion Energy, raised a whopping $425 million round of venture capital. On top of all that there’s the Palisades nuclear power plant in Michigan, which is targeted to restart by year’s end, bringing 800 megawatts of new nuclear power online.
Heading into the second Trump term, there were plenty of indications that the administration would support this technology with increasingly bipartisan appeal. So it wasn’t exactly a surprise that while the One Big Beautiful Bill eviscerated tax credits for solar and wind, it preserved them for both existing and new nuclear facilities. Now that this support is assured, Stein expects the nuclear announcements to keep rolling in. “We might have seen more deals earlier this year if there wasn’t uncertainty about what was going to happen with tax credits. But now that that’s resolved, I expect to hear more later this year,” he told me.
How much of this is, I asked him, is due to data centers and their seemingly insatiable demand for clean, firm power? “Most of it,” he said simply. By way of example, he pointed out how data center load growth has changed the outlooks for two small modular reactor companies in particular. “NuScale has been trying to find their first project for a long time now, after they had to cancel their [Utah Associated Municipal Power Systems] project. Kairos didn’t have a clear buyer for its first-of-a-kind, even though it was building two test reactors,” Stein explained. “Then all of a sudden, they all had additional deals in the works because of data center demand.”
Last year, Kairos inked a 500-megawatt deal with Google to meet the hyperscaler’s growing data center needs, while this year, Texas A&M selected the company — along with three others — to build a reactor at the university’s research and development campus. And while NuScale infamously canceled its first project in 2023 due to rising costs, this year it received approval from the Nuclear Regulatory Commission for a new and improved reactor design. Now the company’s CEO, John Hopkins, told Reuters that NuScale is in talks to deploy its tech with five unnamed “tier one hyperscalers.” Its stock is up more than 150% on the year.
That’s a big turnaround for a company that, less than two years ago, was widely considered a cautionary tale — and it’s not the only one in the industry with this type of comeback story. Right before NuScale’s project failed, another nuclear company, X-energy, announced that it would no longer go public due to “challenging market conditions” and “peer company trading performance.” But while X-energy still has yet to IPO, it appears to be doing just fine. In February, the company announced the close of a $700 million Series C follow-on round, coming on the heels of Amazon’s strategic investment last year.
“I think every company has their stories about how things are changing,” Seth Grae, CEO of the advanced nuclear fuel company Lightbridge, told me. Things have moved a lot faster, Grae said, since Trump released a series of executive orders aimed at accelerating nuclear energy deployment. “Just since May, we’ve received this highly enriched uranium [from the Department of Energy], made these fuel samples, got them qualified already at Idaho National Lab. We expect they’ll be in the reactor this year. Grae told me. “Things didn’t used to happen that fast in nuclear.”
Trump’s plans to fast track nuclear development have also raised serious concerns, however, as critics worry that acceleration could lead to laxer safety standards The executive orders call for, among other things, cutting staff at the Nuclear Regulatory Commission, just as the industry enters a period of intense activity. In June, the President fired one of the agency’s commissioners, Christopher Hanson, without cause. Another commissioner, Annie Caputo, resigned in July.
But right now, the nuclear industry is mostly basking in optimism. Grae credits the government’s strong support for the surge in nuclear stocks — Lightbridge’s own stock price has jumped 180% this year, while another nuclear fuel company, Centrus Energy, is up even more. The small modular reactor company Oklo is up 285% for the year, on the heels of last year’s 12-gigawatt non-binding deal with the data center company Switch — one of the largest corporate clean power agreements to date.
Last year’s slew of deals involving Oklo, X-energy, and Kairos show that the sector’s momentum had been building well before Trump took office. By 2023, the writing was already on the wall in terms of data center load growth, as grid planners began to predict a sharp rise in electricity demand after over a decade of stagnation. But when I asked Erik Funkhauser of the Good Energy Collective whether the prior two years compared with this one, he concurred with Stein. “Nope,” he told me. “We’re seeing capital infusion at a really, really high pace, as high of a pace as the company’s suppliers can keep up with on projects”
Still, the party may not go on forever. “I see a potential for a Valley of Death,” Stein told me, similar to what many startups go through when they’re trying to raise later-stage funding rounds.
“If things don’t start to actually move forward with real progress, either getting licenses or building prototypes on time, then all of that investment will be pulled back.” That’s what the U.S. saw during the last so-called “nuclear renaissance” in the late 2000s, he explained, when a rash of large reactors were proposed with only two actually reaching completion.
These were the notorious Vogtle reactors 3 and 4 in Georgia, which finally came online in 2023 and 2024 respectively, running billions over budget and years behind schedule. In order for this latest round of nuclear enthusiasm to avoid the same fate, Stein told me it’s critical that leading projects demonstrate enough early success to maintain developer confidence in the economic and technical viability of new — and old — nuclear technologies
That being said, the sector will inevitably contract. “Back when we saw this last scale-up, there were three designs that were really competing for attention, and now there are 75. So we’re going to see a lot of failures,” Stein said. The question for venture investors, he told me, is “how many failures of startups that you didn’t invest in are you willing to tolerate before you start to think the whole segment has trouble?”
The second main way this could all fall to pieces, he told me, is if “somebody tries to move too fast,” and that recklessness leads to “either a bankruptcy or an accident or something like that that will send ripples or shock waves through the whole sector.”
Indeed, a metaphorical or literal meltdown in the sector could put a quick halt to this year’s frenzied momentum. But within the next few years, as these announced projects begin to line up their licenses and come online — or fall apart— we’ll soon see whether this latest nuclear revival is a true turning point or just another bubble.
On the Senate’s climate whip, green cement deals, and a U.S. uranium revival.
Current conditions: Flash flooding strikes the Southeastern U.S. • Monsoon rains unleash landslides in southern China • A heat dome is bringing temperatures of up to 107 degrees Fahrenheit to France, Italy, and the Balkans.
An August 5 chart showing last month's record electricity demand peaks.EIA
The United States’ demand for electricity broke records twice last month. Air conditioners cranking on hot days, combined with surging demand from data centers, pushed the peak in the Lower 48 states to a high of 758,053 megawatts on July 28, between 6 p.m. and 7 p.m. EST, data from the U.S. Energy Information Administration’s Hourly Electric Grid Monitor shows. The following day, peak demand set another record, hitting 759,180 megawatts. That’s nearly 2% above the previous record set on July 15, 2024.
The EIA predicted demand to grow by more than 2% per year between 2025 and 2026. Forecasts are even higher in areas with large data centers and factories underway, such as Texas and northern Virginia. The milestone comes as the Trump administration cracks down on solar and wind energy, two of the fastest-growing and quicker-to-build sources of new generation. On Tuesday, The New York Times reported that the Environmental Protection Agency is moving to eliminate $7 billion in spending on grants for solar energy, though when Heatmap’s Emily Pontecorvo asked the agency, it said only that, “With the passage of the One Big Beautiful Bill, EPA is working to ensure Congressional intent is fully implemented in accordance with the law.”
Senator Brian Schatz, a Democrat from Hawaii, locked down enough votes on Tuesday to replace Illinois Senator Dick Durbin as the Democrats’ whip in the chamber. Durbin, who is retiring next year, has served in the Senate Democrats’ No. 2 position since 2005. In his endorsement on Tuesday, Senate Minority Leader Chuck Schumer of New York called Schatz “a close friend and one of my most valued allies.”
Schatz crusaded for the Inflation Reduction Act and told Heatmap he supported last year’s failed bipartisan permitting reform deal, even as progressive greens campaigned against its giveaways to fossil fuels. In a Shift Key podcast interview with my colleague Robinson Meyer and his co-host, Princeton professor Jesse Jenkins, in February, Schatz pitched a big tent for climate action. “We all have to hang together. It’s the American Clean Power Association. It’s the energy company that does both clean and fossil energy. It’s the transmission and distribution companies. It’s the manufacturers. It’s labor. It’s Wall Street. It’s K Street. Everyone has to hang together and say, not only is this good for business, but there’s something that is foundationally worse for business than any individual policy decision.”
Get Heatmap AM directly in your inbox every morning:
The Trump administration may be clawing back funding for cleaning up heavy industry, but Big Tech is still inking deals. On Monday, Amazon agreed to buy low-carbon cement from the startup Brimstone. Then on Tuesday, the data center developer STACK Infrastructure announced the completion of “a pilot pour” of green cement from rival startup Sublime. The moves highlight the growing demand for cleaner industrial materials amid increased scrutiny of the energy and pollution linked to server farms.
America’s uranium enrichment went out of business in the early 2000s after the Clinton-era megatons-to-megawatts program essentially ceded the industry to cheap Russian imports made from disassembled atomic weapons. Since banning imports from Russia last year, the U.S. has been ramping up funding for nuclear fuel again, especially as the industry looks to build new types of reactors that rely on fuel other than the low-enriched uranium that virtually all the country’s operating 94 commercial reactors use. On Monday, the Department of Energy announced its first pilot project for advanced nuclear fuels, giving the startup Standard Nuclear the first federal deal. On Tuesday, the agency signed a $1.5 billion deal to restore the so-called Atomic City on the 100-acre parcel of federal land at the former Paducah Gaseous Diffusion Plan in Kentucky.
The Trump administration gave permission to the National Weather Service to hire up to 450 meteorologists, hydrologists, and radar technicians after sweeping cuts from the Department of Government Efficiency, CNN’s Andrew Freedman reported. The agency, which was partly blamed for its warnings going unheeded ahead of the deadly Texas floods last month, also received an exemption from the federal hiring freeze.
The move came the same day as a federal judge blocked the administration from diverting billions of dollars in Federal Emergency Management Agency funding for disaster resilience and flood mitigation. The injunction warned FEMA against spending the money on anything else.
Beyond Meat is finally getting beyond meat. The company plans to shed the flesh reference in its name this week as it launches its new Beyond Ground product that promises more protein than ground beef. “With this launch,” Fast Company’s Clint Rainey reported, “Beyond Meat is becoming merely Beyond and turning its focus away from only mimicking animal proteins to letting plant-based proteins speak for themselves. The radical move is cultural, agricultural, and financial.”
Rob and Jesse talk through the proposed overturning of the EPA’s “endangerment finding” on greenhouse gases with Harvard Law School’s Jody Freeman.
The Trump administration has formally declared that carbon dioxide and other greenhouse gases are not dangerous pollutants. If the president gets his way, then the Environmental Protection Agency may soon surrender any ability to regulate heat-trapping pollution from cars and trucks, power plants, and factories — in ways that a future Democratic president potentially could not reverse.
On this week’s episode of Shift Key, we discuss whether Trump’s EPA gambit will work, the arguments that the administration is using, and what it could mean for the future of U.S. climate and energy policy. We’re joined by Jody Freeman, the Archibald Cox Professor of Law at Harvard and the director of Harvard’s environmental and energy law program. She was an architect of the Obama administration’s landmark deal with automakers to accept carbon dioxide regulations.
Shift Key is hosted by Jesse Jenkins, a professor of energy systems engineering at Princeton University, and Robinson Meyer, Heatmap’s executive editor.
Subscribe to “Shift Key” and find this episode on Apple Podcasts, Spotify, Amazon, YouTube, or wherever you get your podcasts.
You can also add the show’s RSS feed to your podcast app to follow us directly.
Here is an excerpt from our conversation:
Robinson Meyer: I just want to make a related question, which is, you can actually say some of the sentences in the DOE report — you can believe tornadoes don’t show any influence from climate change and still believe heatwaves do, and still believe extreme rainfall events do. In fact, you could believe the cost of heat waves getting worse could justify the entire regulatory edifice.
Jody Freeman: What I love about you, Rob, right now, is you’re kind of incensed about little points that might individually sort of be right, maybe each one separately, but none of it adds up to even a chink in the armor. Right? And what’ll have to happen is the scientific community writ large, en masse, is going to have to come back and say, even if one or two or three of these sentences could possibly, plausibly be actually accurate, it does nothing to change the overwhelming —
Jesse Jenkins: It doesn’t matter.
Freeman: Right. What I think is happening is we’re all getting poked and distracted and tweaked into outrage over science, when in fact, the first argument they’re making is the one where they could actually attract some judges and justices to say, Oh wait, maybe you have a little more discretion here to set a threshold level. You know, Maybe it matters that you’re saying nothing we do here in the U.S. will make a difference in the end to global warming, and maybe that is a reason you don’t want to regulate. Hmm, maybe we’ll accept that reason. And that’s what we need, I think, to be more concerned about.
Jenkins: You’re saying, don’t get distracted by the fight over the climate science. That fight is very clear. It’s this legal argument that this isn’t an air pollutant because it’s not a local air pollutant, it mixes globally with all the other CO2, and we can’t, you know, each class of cars is a tiny contributor to that, and so we shouldn’t worry about it —
Freeman: And much of this is a replay, or a rehash of arguments that the George W. Bush administration lost in Massachusetts vs. EPA. So a lot of this is like, let’s take another run at the Supreme Court.
Mentioned:
The EPA Says Carbon Pollution Isn’t Dangerous. What Comes Next?
The EPA on its reconsideration of the endangerment finding
Jody’s story on the change: Trump’s EPA proposes to end the U.S. fight against climate change
Jesse’s upshift (and accompanying video); Rob’s sort of upshift.
This episode of Shift Key is sponsored by …
Accelerate your clean energy career with Yale’s online certificate programs. Gain real-world skills, build strong networks, and keep working while you learn. Explore the year-long Financing and Deploying Clean Energy program or the 5-month Clean and Equitable Energy Development program. Learn more here.
Join clean energy leaders at RE+ 25, September 8–11 in Las Vegas. Explore opportunities to meet rising energy demand with the latest in solar, storage, EVs, and more at North America’s largest energy event. Save 20% with code HEATMAP20 at re-plus.com.
Music for Shift Key is by Adam Kromelow.