How Reflective Paint Brings Down Scorching City Temperatures
Communities fight urban heat islands with technologies shielding roofs and pavement
Communities fight urban heat islands with technologies shielding roofs and pavement
Cities across the U.S. have found relief from this summer’s record-setting heat with the help of technologies that shield roofs, pavement and other surfaces from the sun’s scorching rays.
Some of these technologies have been around for more than a decade but are experiencing greater demand as global temperatures rise. Washington, D.C., for example, has built more than 3,200 green roofs covering 9 million square feet—up from about 300,000 square feet in 2006, according to federal and city officials.
Other technologies, such as super-reflective coatings for pavement, streets and windows, are just now becoming effective and affordable enough for widespread use.
The Los Angeles neighbourhood of Pacoima, a densely packed location sandwiched between freeways and an industrial area, has created a partnership with GAF, a New Jersey-based roofing manufacturer, to paint a basketball court, local park and neighbourhood streets with a reflective coating.
“There’s a lot of asphalt and lack of investment for tree canopies,” said Melanie Paola Torres, 24 years old, a community organiser with the group Pacoima Beautiful. “Given the fact that we are in an industrial zone, that contributes to the urban heat-island effect.”
The reflective coating has reduced air temperatures in the test area at 6 feet above ground by 3.5 degrees Fahrenheit during extreme heat days, and surface temperatures by 10 degrees, according to Jeff Terry, GAF’s vice president of corporate social responsibility and sustainability.
Sweltering conditions are worse in urban heat islands, which can be 10 degrees hotter than surrounding suburbs and occur as buildings, roads and other infrastructure absorb and re-emit the sun’s energy.
Cooling technologies mitigate this. Green roofs absorb heat before it penetrates the buildings beneath. Super-reflective coatings reflect the sun’s visible light and invisible infrared radiation away from surfaces to keep them cooler. And an ultra-white paint developed at Purdue University promises even more protection, although the product isn’t commercially available yet. Each strategy helps reduce energy use.
“The important thing is to help people cool their homes and workplaces affordably,” said Jane Gilbert, chief heat officer for Miami-Dade County, which experienced a record 46 straight days of a 100-degree-plus heat index this summer. “The more efficient we can make both the buildings and the AC systems themselves, the less we’re contributing both to greenhouse gases and also waste heat that goes to our urban heat islands.”
Miami is one of the most vulnerable cities to the urban heat-island effect, along with San Francisco, New York, Chicago and Seattle, according to an analysis by Climate Central, a New Jersey-based nonprofit that researches the effects of climate change. Its analysis found that 41 million people living in 44 cities face an urban heat-island effect of at least 8 degrees. Nine U.S. cities had at least one million people exposed to urban heat of 8 degrees or higher because of the local built environment.
To fight the heat, some cities are leveraging federal money and other incentives to persuade local builders to turn office buildings greener and cooler.
In Miami-Dade County, officials used federal funds to outfit 1,700 public housing units with new low-energy air-conditioning units. Local officials also offered a successful amendment to the Florida state building code requiring cool reflective roofs on all new commercial buildings beginning in 2024, and enrolled 150 structures in a voluntary energy-audit program to track improvements to cut energy use and keep temperatures down.
New York, Chicago, Philadelphia, Toronto and other cities are pushing green roofs with tax breaks and other incentives in an effort to lower energy bills and reduce ambient temperatures, according to Steven Peck, president of Green Roofs for Healthy Cities, a Toronto-based green-roof and -wall industry association. Peck said green roofs can be 30 to 40 degrees cooler than a similar-size blacktop roof, while also cutting waste heat from air-conditioning units.
In the Los Angeles neighbourhood of Pacoima, Torres says residents tell her the streets and playgrounds feel cooler since the reflective coating was completed in August 2022.
“The number-one thing that always comes up is the heat waves when you’re looking down the street,” Torres said. “They don’t see those anymore.”
The next step is to install reflective roofing material on a handful of homes as part of the neighbourhood cooling effort. “We want to keep stacking the solutions to overall create a cool community with multiple strategies,” Torres said.
Altering the urban landscape to adapt to extreme heat requires money and technical know-how, according to city leaders and academic experts. But they also acknowledge the need to keep people safe as global temperatures rise.
“Any one solution is not going to necessarily be able to address the entire problem, but by systematically applying solutions that work in each individual location, we can make a dent in the urban heat-island effect,” said David Sailor, professor of geographical sciences and urban planning at Arizona State University.
Consumers are going to gravitate toward applications powered by the buzzy new technology, analyst Michael Wolf predicts
Chris Dixon, a partner who led the charge, says he has a ‘very long-term horizon’
Concern about electric vehicles’ appeal is mounting as some customers show a reluctance to switch
Auto dealers across many parts of the country say electric vehicles are becoming too hard a sell for buyers worried about the range, reliability and price of these models.
When Paul LaRochelle heard Ford Motor was coming out with an electric pickup truck, the dealer was excited about the prospects for his business.
“We thought we could build a million of them and sell them,” said LaRochelle, a vice president at Sheehy Auto Stores, which sells vehicles from a dozen brands in Virginia, Maryland and Washington, D.C.
The reality has been less positive. On Sheehy’s car lots, LaRochelle says there is a six- to 12-month supply of EVs, compared with a month of gasoline-powered vehicles.
With automakers set to release a barrage of new electric models in the coming years, concerns are mounting among auto retailers about whether the technology will have broader appeal given that many customers are still reluctant to make the switch.
Battery-powered models have been piling up on car lots, dealers say, as EV sales growth has slowed in the U.S. this year. Car companies have been offering a combination of discounts and lower interest-rate deals in an effort to juice demand. But it hasn’t been enough, because buyer reticence extends beyond the price tag, dealers say.
“I’m not hearing the consumer confidence in the technology,” said Mary Rice, dealer principal at Toyota of Greensboro in North Carolina. “People aren’t beating down the door to buy these things, and they all have a different excuse why they aren’t buying one.”
Customers cite concerns about vehicles burning through a battery charge faster in cold weather or not being able to travel as far as they expected on a single charge, dealers say. Potential buyers also worry that chargers aren’t as readily accessible as gas stations or might be broken.
Franchise dealerships fear that the push to roll out new models will inundate them with hard-to-sell vehicles. Research firm S&P Global Mobility said there are 56 EV models for sale in the U.S. this year, and the number is expected to nearly double to 100 next year.
“I start to think, you know maybe we should just all pump the brakes a little bit,” Rice said.
A group of dealers expressed their concerns about the government’s role in pushing electric vehicles in a letter last month to President Biden.
A Toyota Motor spokesman said the majority of dealers have become “increasingly more confident in their ability to sell Toyota EV products.”
At Ford, the company’s electric-vehicle sales are rising, including for its F-150 Lightning pickup, but demand isn’t evenly spread across the country, according to a spokesman.
Dealers say that after selling an EV, they sometimes hear complaints about charging and the vehicles not always meeting their advertised range. In some cases, customers seek to return them to the dealer shortly after buying them.
“We have a steady number of clients that have attempted to or flat out returned their car,” said Sheehy’s LaRochelle.
While EVs remain a small but rapidly expanding part of the new-car market, the pace of growth has slowed this year. Electric-vehicle sales increased 48% in the first 11 months, compared with a 69% jump during the same period in 2022, according to Motor Intelligence. Sales remain concentrated in a few states, with California accounting for the largest chunk, S&P Global Mobility data found.
The cooling growth has raised broader questions in the industry about whether car companies face a temporary hurdle or a longer-term demand challenge. Automakers have invested billions of dollars to bring more EV models to the market, and many analysts and car executives say they remain optimistic that sales will continue to expand.
“Although the rate of growth has slowed recently, EV demand is clearly moving in the right direction,” said General Motors Chief Executive Mary Barra on a recent conference call with analysts. A combination of more affordable model options and better charging infrastructure would help encourage more people to buy electric vehicles, she said.
There are also varying views within the dealer community about how quickly buyers will adopt the technology.In hot spots for electric-vehicle demand, such as Los Angeles, dealers say their battery-powered models are some of their top sellers. Those popular EV markets also tend to have more mature public charging networks.
Selling an electric car or truck outside of those demand centres is proving more difficult.
Longtime EV owner Carmella Roehrig thought she was ready to go full-electric and sold her backup gasoline vehicle. But after the 62-year-old North Carolina resident found herself stranded last year in a rural area of South Carolina, she changed her mind. Roehrig’s Tesla Model S got a flat tire, but none of the stores in the area carried tires for a Tesla. She ended up paying a worker at a nearby shop to drive her home.
Roehrig still has her Tesla but bought a pickup truck for long road trips.
Tesla didn’t respond to a request for comment.
“I have these conversations with people who say we’ll all be in EVs in 15 years. I say: ‘I’m not so sure. I’ve tried to do it,’” Roehrig said. “I think you need a gas backup.”
Customers who want to ditch their gas vehicle for environmental reasons are sometimes hesitant, said Mickey Anderson, president of Baxter Auto Group, which owns dealerships in Kansas, Nebraska and Colorado.
“We’re in the Colorado Springs market. If this is your sole mode of transportation, and you’re in a market in extremes of elevation and temperature, the actual range is very limited,” Anderson said. “It makes it extremely impractical.”
Dealers representing around 4,000 stores across the U.S. signed the letter in November addressed to Biden, saying the administration’s proposed auto-emissions regulations designed to promote electric-vehicle sales are unrealistic. The signatories ranged from stores owned by family businesses to publicly held giants such as AutoNation and Lithia Motors.
“Some customers are in the market for electric vehicles, and we are thrilled to sell them. But the majority of customers are simply not ready to make the change,” the letter said.
Some carmakers are pushing back EV-rollout plans. GM said in mid-October that it would delay the opening of an electric pickup plant by a year to late 2025. In response to weaker-than-expected consumer demand, Ford said in late October that it would defer $12 billion of planned spending on electric-vehicle investment.
Since September, dealers on average took more than two months to sell an EV, compared with 40 days for all vehicles, according to car-shopping website Edmunds.
While discounts have helped boost sales of some electric vehicles, they also have led to repercussions for some current owners because it reduces the value of their vehicles, dealers say.
“Most people don’t have the confidence to buy an EV and know what it will be worth in 10-15 years,” said Rice from the Toyota dealership.
It may take some time for the industry to adjust because it is still in an early stage of switching to electric vehicles, Sheehy’s LaRochelle said.
“We’re asking for this market to grow organically,” he said.
Consumers are going to gravitate toward applications powered by the buzzy new technology, analyst Michael Wolf predicts
Chris Dixon, a partner who led the charge, says he has a ‘very long-term horizon’