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.
A conversation with VDE Americas CEO Brian Grenko.
This week’s Q&A is about hail. Last week, we explained how and why hail storm damage in Texas may have helped galvanize opposition to renewable energy there. So I decided to reach out to Brian Grenko, CEO of renewables engineering advisory firm VDE Americas, to talk about how developers can make sure their projects are not only resistant to hail but also prevent that sort of pushback.
The following conversation has been lightly edited for clarity.
Hiya Brian. So why’d you get into the hail issue?
Obviously solar panels are made with glass that can allow the sunlight to come through. People have to remember that when you install a project, you’re financing it for 35 to 40 years. While the odds of you getting significant hail in California or Arizona are low, it happens a lot throughout the country. And if you think about some of these large projects, they may be in the middle of nowhere, but they are taking hundreds if not thousands of acres of land in some cases. So the chances of them encountering large hail over that lifespan is pretty significant.
We partnered with one of the country’s foremost experts on hail and developed a really interesting technology that can digest radar data and tell folks if they’re developing a project what the [likelihood] will be if there’s significant hail.
Solar panels can withstand one-inch hail – a golfball size – but once you get over two inches, that’s when hail starts breaking solar panels. So it’s important to understand, first and foremost, if you’re developing a project, you need to know the frequency of those events. Once you know that, you need to start thinking about how to design a system to mitigate that risk.
The government agencies that look over land use, how do they handle this particular issue? Are there regulations in place to deal with hail risk?
The regulatory aspects still to consider are about land use. There are authorities with jurisdiction at the federal, state, and local level. Usually, it starts with the local level and with a use permit – a conditional use permit. The developer goes in front of the township or the city or the county, whoever has jurisdiction of wherever the property is going to go. That’s where it gets political.
To answer your question about hail, I don’t know if any of the [authority having jurisdictions] really care about hail. There are folks out there that don’t like solar because it’s an eyesore. I respect that – I don’t agree with that, per se, but I understand and appreciate it. There’s folks with an agenda that just don’t want solar.
So okay, how can developers approach hail risk in a way that makes communities more comfortable?
The bad news is that solar panels use a lot of glass. They take up a lot of land. If you have hail dropping from the sky, that’s a risk.
The good news is that you can design a system to be resilient to that. Even in places like Texas, where you get large hail, preparing can mean the difference between a project that is destroyed and a project that isn’t. We did a case study about a project in the East Texas area called Fighting Jays that had catastrophic damage. We’re very familiar with the area, we work with a lot of clients, and we found three other projects within a five-mile radius that all had minimal damage. That simple decision [to be ready for when storms hit] can make the complete difference.
And more of the week’s big fights around renewable energy.
1. Long Island, New York – We saw the face of the resistance to the war on renewable energy in the Big Apple this week, as protestors rallied in support of offshore wind for a change.
2. Elsewhere on Long Island – The city of Glen Cove is on the verge of being the next New York City-area community with a battery storage ban, discussing this week whether to ban BESS for at least one year amid fire fears.
3. Garrett County, Maryland – Fight readers tell me they’d like to hear a piece of good news for once, so here’s this: A 300-megawatt solar project proposed by REV Solar in rural Maryland appears to be moving forward without a hitch.
4. Stark County, Ohio – The Ohio Public Siting Board rejected Samsung C&T’s Stark Solar project, citing “consistent opposition to the project from each of the local government entities and their impacted constituents.”
5. Ingham County, Michigan – GOP lawmakers in the Michigan State Capitol are advancing legislation to undo the state’s permitting primacy law, which allows developers to evade municipalities that deny projects on unreasonable grounds. It’s unlikely the legislation will become law.
6. Churchill County, Nevada – Commissioners have upheld the special use permit for the Redwood Materials battery storage project we told you about last week.
Long Islanders, meanwhile, are showing up in support of offshore wind, and more in this week’s edition of The Fight.
Local renewables restrictions are on the rise in the Hawkeye State – and it might have something to do with carbon pipelines.
Iowa’s known as a renewables growth area, producing more wind energy than any other state and offering ample acreage for utility-scale solar development. This has happened despite the fact that Iowa, like Ohio, is home to many large agricultural facilities – a trait that has often fomented conflict over specific projects. Iowa has defied this logic in part because the state was very early to renewables, enacting a state portfolio standard in 1983, signed into law by a Republican governor.
But something else is now on the rise: Counties are passing anti-renewables moratoria and ordinances restricting solar and wind energy development. We analyzed Heatmap Pro data on local laws and found a rise in local restrictions starting in 2021, leading to nearly 20 of the state’s 99 counties – about one fifth – having some form of restrictive ordinance on solar, wind or battery storage.
What is sparking this hostility? Some of it might be counties following the partisan trend, as renewable energy has struggled in hyper-conservative spots in the U.S. But it may also have to do with an outsized focus on land use rights and energy development that emerged from the conflict over carbon pipelines, which has intensified opposition to any usage of eminent domain for energy development.
The central node of this tension is the Summit Carbon Solutions CO2 pipeline. As we explained in a previous edition of The Fight, the carbon transportation network would cross five states, and has galvanized rural opposition against it. Last November, I predicted the Summit pipeline would have an easier time under Trump because of his circle’s support for oil and gas, as well as the placement of former North Dakota Governor Doug Burgum as interior secretary, as Burgum was a major Summit supporter.
Admittedly, this prediction has turned out to be incorrect – but it had nothing to do with Trump. Instead, Summit is now stalled because grassroots opposition to the pipeline quickly mobilized to pressure regulators in states the pipeline is proposed to traverse. They’re aiming to deny the company permits and lobbying state legislatures to pass bills banning the use of eminent domain for carbon pipelines. One of those states is South Dakota, where the governor last month signed an eminent domain ban for CO2 pipelines. On Thursday, South Dakota regulators denied key permits for the pipeline for the third time in a row.
Another place where the Summit opposition is working furiously: Iowa, where opposition to the CO2 pipeline network is so intense that it became an issue in the 2020 presidential primary. Regulators in the state have been more willing to greenlight permits for the project, but grassroots activists have pressured many counties into some form of opposition.
The same counties with CO2 pipeline moratoria have enacted bans or land use restrictions on developing various forms of renewables, too. Like Kossuth County, which passed a resolution decrying the use of eminent domain to construct the Summit pipeline – and then three months later enacted a moratorium on utility-scale solar.
I asked Jessica Manzour, a conservation program associate with Sierra Club fighting the Summit pipeline, about this phenomenon earlier this week. She told me that some counties are opposing CO2 pipelines and then suddenly tacking on or pivoting to renewables next. In other cases, counties with a burgeoning opposition to renewables take up the pipeline cause, too. In either case, this general frustration with energy companies developing large plots of land is kicking up dust in places that previously may have had a much lower opposition risk.
“We painted a roadmap with this Summit fight,” said Jess Manzour, a campaigner with Sierra Club involved in organizing opposition to the pipeline at the grassroots level, who said zealous anti-renewables activists and officials are in some cases lumping these items together under a broad umbrella. ”I don’t know if it’s the people pushing for these ordinances, rather than people taking advantage of the situation.”