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:
As heat waves get worse, these fixes will help keep your home cool and energy efficient.
July 2023 will almost certainly be declared the hottest month ever recorded, but it is unlikely to hold that record for long. Climate change is making heat waves more frequent, intense, and longer-lasting across the U.S.
Adapting to this hotter future is often discussed at the scale of a city; measured in early warning systems, green spaces, and cooling centers. But there’s also a lot that individual homeowners can do to help their communities and protect themselves.
While the vast majority of American households — some 88% — use air conditioning for relief, homeowners would be wise to consider a variety of additional, “passive” cooling techniques. These are strategies that can keep your home at a safe temperature during a heat wave if the power goes out, an increasingly likely scenario. They will also save you a bit of money on energy bills. In a sense, adapting your home to extreme heat is just another way of thinking about how to make it more energy efficient.
These retrofits also have wider benefits. Since air conditioners work by transferring heat from inside your house outdoors, these fixes can cool down your neighborhood. They’ll cut carbon emissions and air pollution by lowering demand for electricity. If widely adopted, they’ll also help prevent blackouts and could shrink the amount of renewable energy projects that need to be built to replace fossil fuels, alleviating pressure on conservation.
I spoke with Steve Easley, a building science consultant who specializes in energy efficiency, and Shawn Maurer, technical director of the Smart Energy Design Assistance Center at the University of Illinois, about how homeowners should prioritize their options when it comes to passive cooling.
“I always recommend that people do a home energy audit from a certified HERS rater,” Easley told me, referring to the Home Energy Rating System, a nationally recognized system for inspecting and calculating a home’s energy performance. The auditor will tell you how leaky your house is, and how well your roof insulation, windows, and other parts of your house are working to keep out heat, and help you figure out what to attack first. (Easley also recommends getting at least three quotes for any of these solutions, because different contractors bid this work out very differently.)
Below are five things you can do to improve your home’s resilience to heat. Depending on a number of factors — such as where you live, how your house is constructed, and the condition it's in — the mileage you can get out of each of these measures will vary. The good news is that the federal government and many state governments offer tax credits and rebates for most of these solutions. The Inflation Reduction Act created the Energy Efficient Home Improvement tax credit, which offers homeowners up to $1,200 per year to spend on energy efficiency improvements. As part of that, you can claim $150 simply for getting an energy audit.
Maurer said the very first thing he would do to improve the efficiency of a home is to seal up any cracks where air can get in — for example, along the edges of the floors, around the windows, and in the ceiling around light fixtures. “That carries in moisture, heat, and everything from outdoors into the house. It's going to offset any air conditioned air you got inside the house. So air leakage is usually the place we recommend to start,” he said. “And then from there, it's what your budget can handle as far as adding more insulation to your house.”
Insulation comes in a wide range of materials, such as fiberglass and rock wool, blown cellulose, and rigid foam boards. It can be blown into your walls, installed on the floor of the attic, or underneath your roof deck. It’s a jack-of-all-trades when it comes to energy efficiency, since it keeps heat inside in the winter and blocks it from entering in the summer. That means it’s a great option for those in colder climates that also want to prepare their homes for hotter summers.
A 2021 study by a group of researchers at Lawrence Berkeley National Lab modeled the efficacy of a wide array of passive cooling measures in low-income homes in Fresno, California. It found that roof insulation, along with solar-control window films, which we’ll get to in a moment, were the two most effective ways to keep heat from entering the buildings. However, the authors note that roof insulation is an expensive major retrofit, and recommend that it only be done when the roof needs replacement.
A good first step might be finding out what kind of insulation you already have. The most important metric when it comes to insulation is called “R-value,” and the higher the number, the more effective it is. Older homes may have attic insulation as low as R-13, whereas modern building codes typically require insulation between R-38 and R-60.
The new federal tax credit offers up to 30% of the total cost of a project for air sealing and insulation, maxing out at $1,200 total. (Labor costs are not covered by the credit.)
Get one great climate story in your inbox every day:
Having a light-colored roof and exterior will most certainly keep your home cooler than darker options, but not all light colors are created equal. “Cool” roofs and walls are made with special materials that reflect solar energy back into space, preventing it from being absorbed by the building. They also have high “thermal emittance,” meaning they release a lot of the heat that they do absorb, rather than sending it indoors.
All kinds of materials have been developed with these properties. For roofs, there are tiles, shingles, membranes, liquid coatings, and products made of slate, wood, and metal.
Cool roofs don’t necessarily have to be white, although the color does work very well. According to a database maintained by the Cool Roof Ratings Council, the most effective products tend to be bright white coatings, but there are also gray, green, blue, brown, and tan products that are rated highly.
For reflective walls, the most effective products similarly come in white and other light-colored paints, which can reflect 60 to 90 percent of sunlight when new. An extensive 2019 study of reflective wall paints by the same group at Lawrence Berkeley National Lab found that cool walls can reduce annual energy use in single-family homes in warmer U.S. climates by 2% to 8.5%.
Easley said it’s worth considering a cool roof if you have a central air conditioning system in your attic. Otherwise, attics in places like Arizona can get upwards of 130 degrees, taxing the equipment and forcing it to work harder. If your attic isn’t home to your AC, it may only make financial sense to do this kind of retrofit if your house is already in need of a new paint job or your roof needs work.
But it’s probably not worth considering a cool roof if you live in a colder climate, like the Northeast and upper Midwest, since cool roofs can actually make it colder inside in the winter.
There’s no federal incentives for cool roofs, but several states and utilities offer rebates.
This is a big category, and it’s easy to get overwhelmed by the options. Starting with those that will likely cost the most to the least, you can:
• Replace your windows altogether.
• Add storm windows to the interior or exterior of your existing glass.
• Purchase films that can be applied to the existing glass to increase its reflectivity.
• Install external shutters or awnings that block the sun.
• Install interior blinds and curtains that block the sun.
Here’s a rundown of each option.
New windows: Replacing your windows can cost tens of thousands of dollars, so unless they are already in need of repair, you may want to hold off on that option. But when the day does come around, you’ll want to look for “Low-E” windows, which stands for low emissivity. The inside of the glass is coated with microscopic layers of silver that reflect heat while still allowing light to pass through.
Within that category, you’ll also want to look for windows that have what’s called a low “solar heat gain coefficient.” This measures how much heat is absorbed by the glass and transferred inside. It’s rated on a scale of 0 to 1. If you live somewhere that’s sunny year round like Arizona, you ideally want one rated 0.25 or lower.
Through 2032, homeowners can claim up to $600 in federal tax credits for purchasing Energy Star rated windows.
Storm windows: Rather than replacing your windows entirely, it’s far cheaper to install storm windows with Low-E glass, which basically involves bolting another window to the outside of your house. Storm windows have an added benefit of improving air sealing, eliminating drafts.
Film: An even lower-cost option is to look into films with low solar heat gain coefficients that can be applied to existing windows. However, Easeley warned that many manufacturers will void your warranty if you add films to your windows.
Shutters, awnings, blinds, and curtains: Exterior shutters and overhangs that block the sun from ever reaching your windows will generally be more effective than interior shades or blinds, but all of these measures can help. “Window blinds and curtains are really dirt cheap ways to control energy,” said Maurer. “It’s not a very good buffer, but it’s something.”
The Berkeley study on passive cooling measures notes that blinds moderately improve how much heat from the sun enters your home, but they can feel more effective by reducing the sensation of sunlight streaming into your house.
If you still have any incandescent lights, they can also be a significant source of heat. They should be replaced with LED lights.
Planting trees, climbing ivy, and other vegetation can also passively cool your house by shading both your house and any surrounding pavement. However, if you have solar panels, or plan to get them in the future, do not plant trees on the south side of your home as it may reduce the solar system’s effectiveness.
Maurer cautioned that if you do a bunch of work in your home to reduce your cooling needs, you’ll want to keep that in mind if you ever have to replace your air conditioner. He advised having a contractor come in to re-measure what size system you need, since doing a like-for-like replacement will probably be overkill and could result in it malfunctioning.
Read another helpful guide about heat:
Log in
To continue reading, log in to your account.
Create a Free Account
To unlock more free articles, please create a free account.
CEO Mark Zuckerberg confirmed the company’s expanding ambitions in a Threads post on Monday.
Meta is going big to power its ever-expanding artificial intelligence ambitions. It’s not just spending hundreds of millions of dollars luring engineers and executives from other top AI labs (including reportedly hundreds of millions of dollars for one engineer alone), but also investing hundreds of billions of dollars for data centers at the multi-gigawatt scale.
“Meta is on track to be the first lab to bring a 1GW+ supercluster online,” Meta founder and chief executive Mark Zuckerberg wrote on the company’s Threads platform Monday, confirming a recent report by the semiconductor and artificial intelligence research service Semianalysis that
That first gigawatt-level project, Semianalysis wrote, will be a data center in New Albany, Ohio, called Prometheus, due to be online in 2026, Ashley Settle, a Meta spokesperson, confirmed to me. Ohio — and New Albany specifically — is the home of several large data center projects, including an existing Meta facility.
At the end of last year, Zuckerberg said that a datacenter project in Northeast Louisiana, now publicly known as Hyperion, would take 2 gigawatts of electricity; in his post on Monday, he said it could eventually be as large as 5 gigawatts. To get a sense of the scale we’re talking about, a new, large nuclear reactor has about a gigawatt of capacity, while a newly built natural gas plant could supply only around 500 megawatts.
As one could perhaps infer from the fact that their size is quoted in gigawatts instead of square feet or number of GPUs, whether or not these data centers get built comes down to the ability to power them.
Citing information from the natural gas company Williams, Semianalysis reported that Meta “went full Elon mode” for the New Albany datacenter, i.e. is installed its own natural gas infrastructure. Specifically, Williams is building two 200-megawatt facilities, according to the gas developer and Semianalysis, for the Ohio project. (Williams did not immediately respond to a Heatmap request for comment.)
Does this mean Meta is violating its commitments to reach net zero? While the data center buildout may make those goals more difficult to achieve, Meta is still investing in new renewables even as it’s also bringing new gas online. Late last month, the company announced that it was procuring almost 800 new megawatts of renewables from projects to be built by Invenergy, including over 400 megawatts of solar in Ohio, roughly matching the on-site generation from the Prometheus project.
But there’s more to a data center’s climate footprint than what a big tech company does — or does not — build on site.
The Louisiana project, Hyperion, will also be served by new natural gas and renewables added to the grid. Entergy, the local utility, has proposed 1.5 gigawatts of natural gas generation near the Meta site and over 2 gigawatts of new natural gas in total, with another plant in the southern part of the state to help balance the addition of significant new load. In December, when the data center was announced, Meta said that it planned to “bring at least 1,500 megawatts of new renewable energy to the grid.” Entergy did not immediately respond to a Heatmap request for comment on its plans for the Hyperion project.
“Meta Superintelligence Labs will have industry-leading levels of compute and by far the greatest compute per researcher. I'm looking forward to working with the top researchers to advance the frontier!” Zuckerberg wrote.
A new report from the American Council for an Energy-Efficient Economy has some exciting data for anyone attempting to retrofit a multifamily building.
By now there’s plenty of evidence showing why heat pumps are such a promising solution for getting buildings off fossil fuels. But most of that research has focused on single-family homes. Larger apartment buildings with steam or hot water heating systems — i.e. most of the apartment buildings in the Northeast — are more difficult and expensive to retrofit.
A new report from the nonprofit American Council for an Energy-Efficient Economy, however, assesses a handful of new technologies designed to make that transition easier and finds they have the potential to significantly lower the cost of decarbonizing large buildings.
“Several new options make decarbonizing existing commercial and multifamily buildings much more feasible than a few years ago,” Steven Nadel, ACEEE’s executive director and one of the authors, told me. “The best option may vary from building to building, but there are some exciting new options.”
To date, big, multifamily buildings have generally had two flavors of heat pumps to consider. They can install a large central heat pump system that delivers heating and cooling throughout the structure, or they can go with a series of “mini-split” systems designed to serve each apartment individually. (Yes, there are geothermal heat pumps, too, but those are often even more expensive and complicated to install, especially in urban areas.)
While these options have proven to work, they often require a fair amount of construction work, including upgrading electrical systems, mounting equipment on interior and exterior walls, and running new refrigerant lines throughout the building. That means they cost a lot more than a simple boiler replacement, and that the retrofit process can be disruptive to residents.
In 2022, the New York City Housing Authority launched a contest to try and solve these problems by challenging manufacturers to develop heat pumps that can sit in a window just like an air conditioner. New designs from the two winners, Gradient Comfort and Midea, are just starting to come to market. But another emerging solution, central air-to-water heat pumps, also presents an appealing alternative. These systems avoid major construction because they can integrate with existing radiators or baseboard heaters in buildings that currently use hot water boilers. Instead of burning natural gas or oil to produce hot water, the heat pump warms the water using electricity.
The ACEEE report takes the cost and performance data for these emerging solutions and compares it to results from mini-splits, central heat pumps, geothermal heat pumps, packaged terminal heat pumps — all-in-one devices that sit inside a sleeve in the wall, commonly used in hotels — and traditional boilers fed by biogas or biodiesel.
While data on the newer technologies is limited, so far the results are extremely promising. The report found that window heat pumps are the most cost-effective of the bunch to fully decarbonize large apartment buildings, with an average installation cost of $9,300 per apartment. That’s significantly higher than the estimated $1,200 per apartment cost of a new boiler, but much lower than the $14,000 to $20,000 per apartment price tag of the other heat pump variations, although air-to-water heat pumps came in second. The report also found that window heat pumps could turn out to be the cheapest to operate, with a life cycle cost of about $14,500, compared to $22,000 to $30,000 for boilers using biodiesel or biogas or other heat pump options.
As someone who has followed this industry for several years with a keen interest in new solutions for boiler-heated buildings in the Northeast — where I grew up and currently reside — I was especially wowed by how well the new window heat pumps have performed. New York City installed units from both Midea and Gradient in 24 public housing apartments, placing one in each bedroom and living room, and monitored the results for a full heating season.
Preliminary data shows the units performed swimmingly on every metric.
On ease of installation: It took a total of eight days for maintenance workers to install the units in all 24 apartments, compared to about 10 days per apartment when the Housing Authority put split heat pump systems in another building.
On performance: During the winter, while other apartments in the building were baking in 90-degree Fahrenheit heat from the steam system, the window unit-heated apartments maintained a comfortable 75 to 80 degree range, even as outdoor temperatures dropped to as low as 20 degrees.
On energy and cost: The window unit-heated apartments used a whopping 87% less energy than the rest of the building’s steam-heated apartments did, cutting energy costs per household in half.
On customer satisfaction: A survey of 72 residents returned overwhelmingly positive feedback, with 93% reporting that the temperature was “just right” and 100% reporting they were either “neutral” or “satisfied” with the new units.
The Housing Authority found that the units also lowered energy used for cooling in peak summer since they were more efficient than the older window ACs residents had been using. Next, the agency plans to expand the pilot to two full buildings before deploying the units across its portfolio. The pilot was so successful that utilities in Massachusetts, Vermont, and elsewhere are purchasing units to do their own testing.
The ACEEE report looked at a handful of air-to-water heat pump projects in New York and Massachusetts, as well, only two of which have been completed. The average installation cost per apartment was around $13,500, with each of the buildings retaining a natural gas boiler as a backup, but none had published performance data yet.
Air-to-water heat pumps have only recently come to market in the U.S. after having taken off in Europe, and they don’t yet fit seamlessly into the housing stock here. Existing technology can only heat water to 130 to 140 degrees, which is hot enough for the more efficient hot water radiators common in Europe but too cold for the U.S. market, where hot water systems are designed to carry 160- to 180-degree water, or even steam.
These heat pumps can still work in U.S. buildings, but they require either new radiators to be installed or supplemental heat from a conventional boiler or electric resistance unit. The other downside to an air-to-water system is that it can’t provide cooling unless the building is already equipped with compatible air conditioning units.
One strength of these systems over the window units, however, is that they don’t push costs onto tenants in buildings where the landlord has historically paid for heat. They also may be cheaper to operate than more traditional heat pump options, although data is still extremely limited and depends on the use of supplemental heat.
It’s probably too soon to draw any major conclusions about air-to-water systems, anyway, because new, potentially more effective options are on the way. In 2023, New York State launched a contest challenging manufacturers to develop new decarbonized heating solutions for large buildings. Among the finalists announced last year, six companies were developing heat pumps that could generate higher-temperature hot water and/or steam. One of them is now installing its first demonstration system in an apartment building in Harlem, and two others have similar demonstrations in the works.
The ACEEE report also mentions a few other promising new heat pump formats, such as an all-in-one wall-mounted heat pump from Italian company Ephoca. It’s similar to the window heat pump in that it’s contained in a single device rather than split into an indoor and outdoor unit, so it doesn’t require mounting anything to the outside of the building or worrying about refrigerant lines, although it does require drilling two six-inch holes in the wall for vents. These may be a good option for those whose windows won’t accommodate a window heat pump or who don’t like the aesthetics. New York State is also funding product development for better packaged terminal heat pumps that could slot into wall cavities occupied by less-efficient packaged terminal air conditioners and heat pumps today.
Gradient and Midea are not yet selling their cold-climate window heat pumps directly to consumers. Gradient brought a version of its technology for more moderate climates to market in 2023, which was only suitable for heating at outdoor temperatures of 40 degrees and higher. But the company has discontinued that model and is focusing on an “all-weather” version designed for cold climates, which is the one that has been installed in the New York City apartments. Gradient told me it is currently selling that model in bulk to multi-family building owners, utilities, and schools. Midea did not respond to my inquiry.
One big takeaway is that even the new school heat pumps designed to be easier and cheaper to install have higher capital costs than buying a boiler and air conditioners — a stubborn facet of many climate solutions, even when they save money in the long run. Canary Media previously reported that the Gradient product would start at $3,800 per unit and the Midea at $3,000. Experts expect the cost to come down as adoption and demand pick up, but the ACEEE report recommends that states develop incentives and financing to help with up-front costs.
“These are not just going to happen on their own. We do need some policy support for them,” Nadel said. In addition to incentives and building decarbonization standards, Nadel raised the idea of discounted electric rates for heat pump users, an idea that has started to gain traction among climate advocates that a few utilities have piloted.
“To oversimplify,” Nadel said, “in many jurisdictions, heat pumps subsidize other customers, and that probably needs to change if this is going to be viable.”
Editor’s note: This story has been updated to include comment from Gradient.
Current conditions: Two people are missing after torrential rains in Catalonia • The daily high will be over 115 degrees Fahrenheit every day this week in Baghdad, Iraq • The search for victims of the Texas floods is paused due to a new round of rains and flooding in the Hill Country.
Homeland Security Secretary Kristi Noem defended the Federal Emergency Management Agency after The New York Times reported it failed to answer nearly two-thirds of the calls placed to its disaster assistance line by victims of the Central Texas floods. Speaking on NBC’s Meet the Press on Sunday, Noem repudiated reports by the Times and Reuters that her requirement that she personally approve expenses over $100,000, as well as the deployment of other critical resources, created bottlenecks during the crucial hours after the floodwaters receded. “Those claims are absolutely false,” she said.
Noem additionally denied reports that FEMA’s failure to renew the contracts of call-center contractors created a slowdown at the agency. Per the Times’ reporting, FEMA allowed its call center contract extension to expire on the night of July 5, in the midst of the unfolding disaster. During the day on July 5, FEMA answered the calls of 99.7% of survivors seeking one-time assistance for their immediate needs, the Times’ reporting shows; after FEMA failed to renew the contracts and hundreds of contractors were fired, the answer rate dropped to just 35.8% on July 6, and 15.9% on July 7. “Those contracts were in place, no employees were off of work,” Noem told Meet the Press. (Reuters reports that an internal FEMA document shows Noem approved the call center contracts as of July 10.)
At least 120 people died in the flash floods in Texas’ Hill Country over the Fourth of July weekend, with more than 160 people still missing. FEMA has fired or bought out at least 2,000 full-time employees since the start of the year, though since the floods, the Trump administration has reframed its push to “abolish” FEMA as “rebranding” FEMA, instead.
The Trump administration last week fired the final handful of employees who worked at the Office of Global Change, the division of the State Department that focused on global climate negotiations. Per The Washington Post, the employees were the final group at the department working on issues of international climate policy, and were part of bigger cuts to the agency that will see nearly 3,000 staffers out of work. “The Department is undertaking a significant and historic reorganization to better align our workforce activities and programs with the America First foreign policy priorities,” the State Department told the Post in a statement about the shuttering of the office.
Grand Canyon Lodge employees pictured on July 20, 1930. NPS/George Grant
The historic Grand Canyon Lodge burned down in the nearly 6,000-acre Dragon Bravo Fire in Arizona over the weekend. The rustic lodge, located on the Canyon’s remote North Rim, had stood since 1937, when it was rebuilt after a kitchen fire, and was the only hotel located inside the boundaries of the national park.
Arizona Governor Katie Hobbs called for an investigation into the National Park Service’s handling of the fire, which destroyed an additional 50 to 80 structures on the park’s North Rim. “An incident of this magnitude demands intense oversight and scrutiny into the federal government’s emergency response,” she said, adding that “Arizonans deserve answers for how this fire was allowed to decimate the Grand Canyon National Park.” The Dragon Bravo Fire is one of two wildfires burning on the park’s north side and began after a lightning strike on July 4. The famous Phantom Ranch, located inside the canyon, and popular Bright Angel Trail and Havasupai Gardens, were also closed to hikers as of Sunday due to the fires.
Late last week, the local government of Nantucket reached a settlement with GE Vernova for $10.5 million to compensate for the tourism and business losses that resulted from the July 2024 turbine failure at Vineyard Wind 1. The town will use the money to establish a Community Claims Fund to provide compensation to affected parties.
The incident involved a 350-foot blade from a GE Vernova turbine that split off and fell into the water during construction of Vineyard Wind. Debris washed up onshore, temporarily closing some of the Massachusetts island’s iconic beaches during the height of tourist season. “The backlash was swift,” my colleague Emily Pontecorvo reported at the time. “Nantucket residents immediately wrote to Nantucket’s Select Board to ask the town to stop the construction of any additional offshore wind turbines.” Though significant errors like blade failures are incredibly rare, as my colleague Jael Holzman has also reported, the disaster could not have come at a worse time for Vineyard Wind, which subsequently saw its expansion efforts stymied by the Trump administration.
Nineteen states and the territory of Guam moved last week to intervene in a May lawsuit claiming the Trump administration has violated young people’s right to good health and a stable environment. The original complaint was filed in May by 22 plaintiffs represented by Our Children’s Trust — the same Oregon group that brought Held v. Montana, which successfully argued that the state violated young people’s constitutional right to a clean and healthful environment, as well as the groundbreaking climate case Juliana v. United States, which the Supreme Court declined to hear this spring.
In the new Montana-led move, the coalition of states represented by their respective attorneys general is seeking to join the lawsuit as defendants. Per Our Children’s Trust, the plaintiffs will file a formal response to the motion to intervene in the coming weeks.
More than half of all the soybean oil produced in the United States next year will be used to make biofuel, according to a new outlook by the U.S. Department of Agriculture.
Editor’s note: This story has been updated to reflect the current state of the youth climate lawsuit.