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How a panther habitat became a battleground for the state’s environmental groups

About 27 miles inland from Florida’s southwestern coast sit three empty swaths of land among a sea of green. This undeveloped area represents both the future of Florida’s development and the culmination of a 20 year fight between the state’s environmentalists.
“What happens here will change the face of Collier County forever,” April Olson, a researcher at the Conservancy of Southwest Florida, told me.
Home to affluent Naples and its fast-growing population of retirees, the county recently approved plans for four new villages to be built in one of Florida’s last undeveloped areas, which is sandwiched between some of the state’s biggest and most important nature reserves. The region hasn’t enjoyed official protection, per se, but it has enjoyed a special status. But with almost half a million people having moved to Florida just last year, and more on the way, the county of 300,000 inhabitants and counting has decided to keep building.
Yet if this sounds like a typical story of developers versus environmentalists, it isn’t. Instead, it has become a unique point of tension among environmental groups in Florida. While one group believes it’s their responsibility to be a part of this conversation and help manage unavoidable development, the other side believes it’s their role to fight against it.
“I’m very surprised environmentalists are taking this pragmatic approach,” said Matthew Schwartz, executive director of the South Florida Wildlands Association. “This isn’t what environmentalists do.”
The result is a rift among the guardians of Florida’s wildlife.
The environmentalists all agree on what they’re trying to protect: the panthers. From a conservation perspective, the region has acted as a corridor for the state’s remaining endangered panthers, of which there are only 120-230 adults left in the wild, to travel.
The area is surrounded by protected nature reserves. To the north is a complex of wildlife, bird sanctuaries, and wetlands; to the northeast are two different wildlife management areas, and to the south is the Florida panther national wildlife refuge, another wildlife management area that is home to bears, a state forest, a state preserve, and a national preserve that ultimately extends into the Everglades.
“This area is a mosaic of habitat types that allows the panther to live,” said Schwartz. “What they are doing essentially fragmented those complexes from one another.”
But to understand how the area has become a battleground of environmentalist groups, you’ll first have to dive into the area’s weird regulatory history.
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The villages being constructed amid this remarkably untouched land are the most recent outcome of a partnership between developers, land owners, and environmental groups. Called the Rural Lands Stewardship Area (RLSA) program, this partnership changed zoning over 20 years ago to allow for more dense development in exchange for environmental protections.
“At the end of the day, the RLSA is a compromise,” said Meredith Budd, who worked on this project when she was a policy director at the Florida Wildlife Federation. (She is now the director of external affairs for the Live Wildly Foundation.)
The RLSA was born way back in 1999, when then-Florida Governor Jeb Bush put a moratorium on development in Collier County. He claimed that urban sprawl in Naples, the state’s fastest growing city at the time, had gotten out of hand and that everyone needed to figure out a better solution for development that preserved agricultural lands and protected the environment.
When the RLSA was first discussed and proposed in 2002, most environmentalist groups, including the Conservancy of Southwest Florida, were on board. The battle that has emerged among these groups has its roots in some imprecise wording from the original proposal that almost tripled the amount of land that developers could build on.
The total area was — and still is — about 198,000 acres. Just over half of the acreage is protected nature reserves, with the rest mostly agricultural land available for development. But there’s a catch. Prior to the RLSA, the zoning only allowed for a single house, called a “ranchette,” to be built every five acres on the developable land. While some of these solitary homes exist today on farms, the majority of the area is still uninhabited, therefore serving as a wildlife corridor as well as porous land to absorb heavy rainfall or storm surges.
That’s where the RLSA was supposed to come in. Published in 2002, it proposed to change the allotment, swapping denser housing for more protected land. It indicated that 16,805 acres of the 98,000 available could be built on if developers earned allowances by restoring other land, although what would count as restoration was a little hazy. The language around these numbers was also very vague, critically leaving room to increase the amount of credits able to be earned and, subsequently, the acres developed. It ultimately increased the amount of land up for development to 45,000 acres. Many of the conservancies didn’t realize this change until the five-year review in 2007.
“We were supportive of RLSA,” said Olson. “But we believe the goals are not being met. The public was promised that 16,000 acres would be developed and that 91% of the area would be preserved.”
But those working with the RLSA think what’s done is done. “There’s no point in going back and figuring out what happened,” said Budd. “The allowable footprint is over 40,000 acres. We have to move forward and figure out whether wildlife connections can be made.”
The intent of the 1999 moratorium was to curb development for the benefit of conservation. The RLSA is still attempting to do that, but it’s a voluntary program, and much of the power lies with the landowners.
But in the past few years, Florida’s real estate market has boomed and land use planning regulations have been weakened. This combination made landowners restless to start building, more able to do so, and more impatient when it comes to making concessions to conservationists. Pro-RLSA environmentalists say playing hardball in negotiations with developers just won’t fly anymore.
“These organizations trying to save habitat by killing these programs aren’t helping, they’re making it worse,” said Elizabeth Fleming, a representative at Defenders of Wildlife, which supports the RLSA.
The four new villages, which are cumulatively known as “The Town of Big Cypress,” are only the most recent developments in the RLSA. The first, called Ave Maria, began building in 2005 but construction paused for a while after the recession. Big Cypress is one of the first cohesive plans out of the RLSA to keep building since then, but six more are in development. Though not nearly finished yet, the website for the Town of Big Cypress promises to fulfill all the expectations of the American dream. “Families strolling along storefronts with ice cream cones in hand … on-street parking for easy access to the hair salon, dog groomer, dry cleaner, and local grocer,” the website says. It promises happiness, community, convenience — even good weather and “responsible growth.”.
Today, both sides agree that no development would be the best way forward. “In a perfect world, I would love to see no more of it developed,” said Budd. “If I was Queen, I would say you no longer have property rights.”
Bradley Cornell, policy associate at the Audubon Society of the Western Everglades, helped make the RLSA a reality. “I’d much rather build a wall at the Georgia line and tell everyone to go home,” he said. “But we’re expected to get another 15 million people in Florida over the next 50 years. All of these people are moving to Florida. Where in the hell are we going to put them without ruining Florida’s nature?”
Between July 2021 and 2022, 444,500 people moved to Florida, according to the Tampa Bay Economic Council. Despite the increase in hurricanes and flooding and the decrease in affordable insurance, Florida is more popular than it has ever been.
Those in favor of the RLSA say that development is going to happen with or without them, and the RLSA allows them a platform to negotiate. “This is the best compromise we could have gotten,” Cornell said.
The primary benefit of the RLSA is that it offers a chance at higher density living with a potentially smaller ecological footprint. The pro-RLSA group, for example, has kept some developments from further encroaching on panther habitat. These conservationists have negotiated underpasses and fencing in three different areas to allow panthers and wildlife to cross roads without getting hit. They have also gotten the county to require bear proof trash cans, lowering lights to avoid light pollution, and smoke easements, which require new tenants to sign off on necessary controlled burns to maintain the environment for the panther preserve. From the Town of Big Cypress alone, the RLSA crediting system requires the developers to permanently preserve 12,000 acres. In this case, they will be restoring the hydrology of a major wetland nearby, according to Cornell.
“We’re just trying to have a seat at the table and ensure that we can get the best conservation outcomes knowing that the landowners have the rights to this land and are permitted to do whatever they want,” said Fleming.
The pro-RLSAers also pushed for more protections than they got. For 10 years, they fought for a Habitat Conservation Plan (HCP) that would have legally bound the landowners to certain conservation requirements, according to Budd. But pushback from the anti-RLSA groups slowed the process so much that eventually it wasn’t worth the landowners’ time and it was withdrawn in August 2022. Those against the RLSA had many qualms with the HCP and don’t see its withdrawal as a loss.
The other arguments against the RLSA are plentiful.
The anti-RLSA group contends that any development will harm the panthers. “This project would be the nail in the coffin of the panthers,” said Olson.
This side of the debate also thinks that the zoning rules that predated the RLSA, which previously allowed for ranchettes every five acres, were highly unlikely to practically result in development. They argue that implementing the road infrastructure required for such scattered housing would be prohibitively expensive, suggesting that if the RLSA hadn’t been proposed, this area would have been left untouched.
“It’s highly unlikely that they would come in and build five-acre ranchettes,” said Olson. “They would need thousands of miles of new roads. One new 100 mile road was calculated to cost $111 million in 2015.”
Schwartz agreed. “This is completely unpopulated, undeveloped rural land,” he said. “People don’t want to buy a swath of rural land and move into undeveloped lands.”
But pro-RLSA environmentalists think that perspective is naive. “That’s a false argument,” says Fleming. “It’s based in no reality. People are moving here and that area is the least expensive if you want to be near Naples. I see no reason why that wouldn’t continue.”
Budd added that money is not a concern in this area. “Collier County is one of the highest wealth points in the state, if not the whole country,” she said. “So to say this would be too expensive is unreasonable.”
Another area in between Naples and the RLSA, called Golden Gate Boulevard, had the same one-in-five zoning restrictions as the RLSA and has been heavily developed in the last 10 years.
The RLSA plan also does not seem to be taking the changing climate into account. According to Olson, 96% of Collier County is susceptible to storm surge. The inland parts aren’t as vulnerable, but there is still a high threat and the area’s porosity would be lost with these developments. In addition, the RLSA will experience 109 days where the heat index is above 100 degrees Fahrenheit in 2023, and 138 in 2053, according to The Washington Post’s interactive map on heat waves.
County Commissioner Bill McDaniel said that climate change was not a concern in the process of developing The Town of Big Cypress. “There are no stipulations with regard to climate change because it’s such a nebulous discussion point,” he said.
Though the commissioner agreed that many climate-friendly technologies are comparable, if not less expensive to purchase and maintain, the RLSA does not require developers to install permeable concrete, heat pumps, special shade trees for temperature, or solar panels on the houses.
“We recommended numerous policies that would encourage more energy efficient homes and appliances, improve permeability of sidewalks, require complete street designs that all users can use, ease traffic congestion, increase Florida friendly plants that require less water, include stipulations for storm water runoff, etc.” said Olson. “They just ignored it. I have not once heard the County even discuss heat issues or climate issues.”
Budd said that the choice to build inland in itself is a climate-conscious decision. “When looking at this long term and the threats of climate change, the main threat is that people will be moving inland,” she said. “Where we put the development is the most important thing.”
One of the biggest landowners in the area, named for the county’s namesake, Collier Enterprises, echoed Budd’s sentiment in emailed responses. “The Town of Big Cypress is 19 miles from the coast, similar to Babcock Ranch, which did not sustain damage from the recent Hurricane Ian, having one of the largest reported storm surges ever recorded.” He added that most of the national buildings in the area provide options for energy efficiency and smart home technology
Though both sides have very different ideas of how to be involved in development, they are both aware that development is coming to Eastern Collier County and share the same ultimate desires for the region.
“We do know that the RLSA is going to grow,” said Olson. “We know that Collier County is going to grow. We just think it could be done more sustainably.”
Environmentalists everywhere are grappling with how to best save the last bastion of the lands and animals that sustain us. Depending on which side you take in the RLSA fight, it has become a question of cynicism versus hope or pragmatism versus pipe dreams.
Those against the RLSA are still championing its original goal: to preserve the environment and to curb excessive development. “The goal of the program wasn’t to allow each and every landowner to maximize their profit to the greatest extent,” said Nicole Johnson, Director of Governmental Relations at the Conservancy of Southwest Florida.
The other side has committed to pragmatism. “At the end of the day, the dollar speaks,” said Budd. “And unfortunately it speaks louder than the voices against the project.”
As regulations recede in Florida, the RLSA disagreement signals a philosophical choice environmentalists will increasingly have to make: If we can’t beat them, should we join them?
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Microreactor maker Antares Nuclear just struck a deal with BWXT Technologies to produce TRISO.
Long before the infamous trio of accidents at Three Mile Island, Chernobyl, and Fukushima, nuclear scientists started working on a new type of fuel that would make a meltdown nearly impossible. The result was “tri-structural isotropic” fuel, better known as TRISO.
The fuel encased enriched uranium kernels in three layers of ceramic coating designed to absorb the super hot, highly radioactive waste byproducts that form during the atom-splitting process. In theory, these poppyseed-sized pellets could have negated the need for the giant concrete containment vessels that cordon off reactors from the outside world. But TRISO was expensive to produce, and by the 1960s, the cheaper low-enriched uranium had proved reliable enough to become the industry standard around the globe.
TRISO had another upside, however. The cladding protected the nuclear material from reaching temperatures high enough that could risk a meltdown. That meant reactors using them could safely operate at hotter temperatures. When the United States opened its first commercial high-temperature gas-cooled reactor in 1979, barely three months after Three Mile Island, the Fort St. Vrain Generating Station in Colorado ran on TRISO. It was a short-lived experiment. After a decade, the high cost of the fuel and the technical challenges of operating the lone commercial atomic station in the U.S. that didn’t use water as a coolant forced Fort St. Vrain to close. TRISO joined the long list of nuclear technologies that worked, but didn’t pencil out on paper.
Now it’s poised for a comeback. X-energy, the nuclear startup backed by Amazon that plans to cool its 80-megawatt microreactors with helium, is building out a production line to produce its own TRISO fuel in hopes of generating both electricity for data centers and heat as hot as 1,400 degrees Fahrenheit for Dow Chemical’s petrochemical facilities. Kairos Power, the Google-backed rival with the country’s only deal to sell power from a fourth-generation nuclear technology — reactors designed to use coolants other than water — to a utility, is procuring TRISO for its molten fluoride salt-cooled microreactors, which are expected to generate 75 megawatts of electricity and reach temperatures above 1,200 degrees.
Then there’s Antares Nuclear. The California-based startup is designing 1-megawatt reactors cooled through sodium pipes that conduct heat away from the atom-splitting core. On Thursday, the company is set to announce a deal with the U.S. government-backed nuclear fuel enricher BWXT Technologies to establish a new production line for TRISO to fuel Antares reactors, Heatmap has learned exclusively.
Unlike X-energy or Kairos, Antares isn’t looking to sell electricity to utilities and server farms. Instead, the customers the company has in mind are the types for whom the price of fuel is secondary to how well it functions under extraordinary conditions.
“We’re putting nuclear power in space,” Jordan Bramble, Antares’ chief executive, told me from his office outside Los Angeles.
Just last month, NASA and the Department of Energy announced plans to develop a nuclear power plant on the moon by the end of the decade. The U.S. military, meanwhile, is seeking microreactors that can free remote bases and outposts from the tricky, expensive task of maintaining fossil fuel supply chains. Antares wants to compete for contracts with both agencies.
“It’s a market where cost matters, but cost is not the north star,” Bramble said.
Unlike utilities, he said, “you’re not thinking of cost solely in terms of fuel cycle, but you’re thinking of cost holistically at the system level.” In other words, TRISO may never come as cheap as traditional fuel, but something that operates safely and reliably in extreme conditions ends up paying for itself over time with spacecrafts and missile-defense systems that work as planned and don’t require replacement.
That’s a familiar market for BWXT. The company — spun out in 2015 from Babcock and Wilcox, the reactor developer that built more than half a dozen nuclear plants for the U.S. during the 20th century — already enriches the bulk of the fuel for the U.S. military’s fleet of nuclear submarines, granting BWXT the industry’s highest-possible security clearance to work on federal contracts.
But BWXT, already the country’s leading producer of TRISO, sees an even wider market for the fuel.
“The value is that it allows you to operate at really high temperatures where you get high efficiencies,” Joseph Miller, BWXT’s president of government operations, told me. “We already have a lot of customer intrigue from the mining industry. I can see the same thing for synthetic fuels and desalination.”
BWXT isn’t alone in producing TRISO. Last month, the startup Standard Nuclear raised $140 million in a Series A round to build out its supply chain for producing TRISO. X-energy is establishing its own production line through a subsidiary called TRISO-X. And that’s just in the U.S. Russia’s state-owned nuclear company, Rosatom, is ramping up production of TRISO. China, which operates the world’s only commercial high-temperature gas-cooled reactor at the moment, also generates its own TRISO fuel.
Beijing’s plans for a second reactor based on that fourth-generation design could indicate a problem for the U.S. market: TRISO may work better in larger reactors, and America is only going for micro-scale units.
The world-leading high-temperature gas reactor China debuted in December 2023 maxes out at 210 megawatts of electricity. But the second high-temperature gas reactor under development is more than three times as powerful, with a capacity of 660 megawatts. At that size, the ultra-high temperatures a gas reactor can reach mean it takes longer for the coolant — such as the helium used at Fort St. Vrain — to remove heat. As a result, “you need this robust fuel form that releases very little radioactivity during normal operation and in accident conditions,” Koroush Shirvan, a researcher who studies advanced nuclear technologies at the Massachusetts Institute of Technology, told me.
But microreactors cool down faster because there’s less fuel undergoing fission in the core. “Once you get below a certain power level,” Shrivan said, “why would you have [TRISO]?”
Given the military and space applications Antares is targeting, however, where the added safety and functionality of TRISO merits the higher cost associated with using it, the company has a better use case than some of its rivals, Shrivan added.
David Petti, a former federal researcher who is one of the leading U.S. experts on TRISO, told me that when the government was testing TRISO for demonstration reactors, the price was at least double that of traditional reactor fuel. “That’s probably the best you could do,” he said in reference to the cost differential.
There are other uranium blends inside the TRISO pellets that could prove more efficient. The Chinese, for example, use uranium dioxide, essentially just an encased version of traditional reactor fuel. The U.S., by contrast, uses uranium oxycarbide, which allows for increased temperatures and higher burnups of the enriched fuel. Another option, which Bramble said he envisions Antares using in the future, would be uranium nitride, which has a greater density of fuel and could therefore last longer in smaller reactors used in space.
“But it’s not as tested in a TRISO system,” Petti said, noting that the federal research program that bolstered the TRISO efforts going on now started in 2002. “Until I see a good test that it’s good, the time and effort it takes to qualify is complicated.”
Since the uranium in TRISO is typically enriched to higher levels than standard fuel, BWXT’s facilities are subject to stricter safety rules, which adds “significant overhead,” Petti said.
“When you make a lot of fuel per year in your fuel factory, you can spread that cost and you can get a number that may be economic,” he said. “When you have small microreactors, you’re not producing an awful lot. You have to take that cost and charge it to the customer.”
BWXT is bullish on the potential for its customer base to grow significantly in the coming years. The company is negotiating a deal with the government of Wyoming to open a new factory there entirely dedicated to TRISO production. While he wouldn’t give specifics just yet, Miller told me BWXT is developing new technologies that can make TRISO production cheaper. He compared the cost curve to that of microchips, an industry in which he previously worked.
“Semiconductors were super expensive to manufacture. They were almost cost prohibitive,” Miller said. “But the cost curve starts to drop rapidly when you fully understand the manufacturing process and you know how to integrate the understanding into operational improvements.”
He leaned back in his chair on our Zoom call, and cracked a smile. “Frankly,” he said, “I feel more confident every day that we’re going to get a really, really cost driven formula on how to manufacture TRISO.”
The startup — founded by the former head of Tesla Energy — is trying to solve a fundamental coordination problem on the grid.
The concept of virtual power plants has been kicking around for decades. Coordinating a network of distributed energy resources — think solar panels, batteries, and smart appliances — to operate like a single power plant upends our notion of what grid-scale electricity generation can look like, not to mention the role individual consumers can play. But the idea only began taking slow, stuttering steps from theory to practice once homeowners started pairing rooftop solar with home batteries in the past decade.
Now, enthusiasm is accelerating as extreme weather, electricity load growth, and increased renewables penetration are straining the grid and interconnection queue. And the money is starting to pour in. Today, home battery manufacturer and VPP software company Lunar Energy announced $232 million in new funding — a $102 million Series D round, plus a previously unannounced $130 million Series C — to help deploy its integrated hardware and software systems across the U.S.
The company’s CEO, Kunal Girotra, founded Lunar Energy in the summer of 2020 after leaving his job as head of Tesla Energy, which makes the Tesla Powerwall battery for homeowners and the Megapack for grid-scale storage. As he put it, back then, “everybody was focused on either building the next best electric car or solving problems for the grid at a centralized level.” But he was more interested in what was happening with households as home battery costs were declining. “The vision was, how can we get every home a battery system and with smart software, optimize that for dual benefit for the consumer as well as the grid?”
VPPs work by linking together lots of small energy resources. Most commonly, this includes solar, home batteries, and appliances that can be programmed to adjust their energy usage based on grid conditions. These disparate resources work in concert conducted by software that coordinates when they should charge, discharge, or ramp down their electricity use based on grid needs and electricity prices. So if a network of home batteries all dispatched energy to the grid at once, that would have the same effect as firing up a fossil fuel power plant — just much cleaner.
Lunar’s artificial intelligence-enabled home energy system analyzes customers’ energy use patterns alongside grid and weather conditions. That allows Lunar’s battery to automatically charge and discharge at the most cost-effective times while retaining an adequate supply of backup power. The batteries, which started shipping in California last year, also come integrated with the company’s Gridshare software. Used by energy companies and utilities, Gridshare already manages all of Sunrun’s VPPs, including nearly 130,000 home batteries — most from non-Lunar manufacturers — that can dispatch energy when the grid needs it most.
This accords with Lunar’s broader philosophy, Girotra explained — that its batteries should be interoperable with all grid software, and its Gridshare platform interoperable with all batteries, whether they’re made by Lunar or not. “That’s another differentiator from Tesla or Enphase, who are creating these walled gardens,” he told me. “We believe an Android-like software strategy is necessary for the grid to really prosper.” That should make it easier for utilities to support VPPs in an environment where there are more and more differentiated home batteries and software systems out there.
And yet the real-world impact of VPPs remains limited today. That’s partially due to the main problem Lunar is trying to solve — the technical complexity of coordinating thousands of household-level systems. But there are also regulatory barriers and entrenched utility business models to contend with, since the grid simply wasn’t set up for households to be energy providers as well as consumers.
Girotra is well-versed in the difficulties of this space. When he first started at Tesla a decade ago, he helped kick off what’s widely considered to be the country’s first VPP with Green Mountain Power in Vermont. The forward-looking utility was keen to provide customers with utility-owned Tesla Powerwalls, networking them together to lower peak system demand. But larger VPPs that utilize customer-owned assets and seek to sell energy from residential batteries into wholesale electricity markets — as Lunar wants to do — are a different beast entirely.
Girotra thinks their time has come. “This year and the next five years are going to be big for VPPs,” he told me. The tide started to turn in California last summer, he said, after a successful test of the state’s VPP capacity had over 100,000 residential batteries dispatching more than 500 megawatts of power to the grid for two hours — enough to power about half of San Francisco. This led to a significant reduction in electricity demand during the state’s evening peak, with the VPP behaving just like a traditional power plant.
Armed with this demonstration of potential and its recent influx of cash, Lunar aims to scale its battery fleet, growing from about 2,000 deployed systems today to about 10,000 by year’s end, and “at least doubling” every year after that. Ultimately, the company aims to leverage the popularity of its Gridshare platform to become a market maker, helping to shape the structure of VPP programs — as it’s already doing with the Community Choice Aggregators that it’s partnered with so far in California.
In the meantime, Girotra said Lunar is also involved in lobbying efforts to push state governments and utilities to make it easier for VPPs to participate in the market. “VPPs were always like nuclear fusion, always for the future,” he told me. But especially after last year’s demonstration, he thinks the entire grid ecosystem, from system operators to regulators, are starting to realize that the technology is here today. ”This is not small potatoes anymore.”
If all the snow and ice over the past week has you fed up, you might consider moving to San Francisco, Los Angeles, Phoenix, Austin, or Atlanta. These five cities receive little to no measurable snow in a given year; subtropical Atlanta technically gets the most — maybe a couple of inches per winter, though often none. Even this weekend’s bomb cyclone, which dumped 7 inches across parts of northeastern Georgia, left the Atlanta suburbs with too little accumulation even to make a snowman.
San Francisco and the aforementioned Sun Belt cities are also the five pilot locations of the all-electric autonomous-vehicle company Waymo. That’s no coincidence. “There is no commercial [automated driving] service operating in winter conditions or freezing rain,” Steven Waslander, a University of Toronto robotics professor who leads WinTOR, a research program aimed at extending the seasonality of self-driving cars, told me. “We don’t have it completely solved.”
Snow and freezing rain, in particular, are among the most hazardous driving conditions, and 70% of the U.S. population lives in areas that experience such conditions in winter. But for the same reasons snow and ice are difficult for human drivers — reduced visibility, poor traction, and a greater need to react quickly and instinctively in anticipation of something like black ice or a fishtailing vehicle in an adjacent lane — they’re difficult for machines to manage, too.
The technology that enables self-driving cars to “see” the road and anticipate hazards ahead comes in three varieties. Tesla Autopilot uses cameras, which Tesla CEO Elon Musk has lauded for operating naturally, like a human driver’s eye — but they have the same limitations as a human eye when conditions deteriorate, too.
Lidar, used by Waymo and, soon, Rivian, deploys pulses of light that bounce off objects and return to sensors to create 3D images of the surrounding environment. Lidar struggles in snowy conditions because the sensors also absorb airborne particles, including moisture and flakes. (Not to mention, lidar is up to 32 times more expensive than Tesla’s comparatively simple, inexpensive cameras.) Radar, the third option, isn’t affected by darkness, snow, fog, or rain, using long radio wavelengths that essentially bend around water droplets in the air. But it also has the worst resolution of the bunch — it’s good at detecting cars, but not smaller objects, such as blown tire debris — and typically needs to be used alongside another sensor, like lidar, as it is on Waymo cars.
Driving in the snow is still “definitely out of the domain of the current robotaxis from Waymo or Baidu, and the long-haul trucks are not testing those conditions yet at all,” Waslander said. “But our research has shown that a lot of the winter conditions are reasonably manageable.”
To boot, Waymo is now testing its vehicles in Tokyo and London, with Denver, Colorado, set to become the first true “winter city” for the company. Waymo also has ambitions to expand into New York City, which received nearly 12 inches of snow last week during Winter Storm Fern.
But while scientists are still divided on whether climate change is increasing instances of polar vortices — which push extremely cold Arctic air down into the warmer, moister air over the U.S., resulting in heavy snowfall — we do know that as the planet warms, places that used to freeze solid all winter will go through freeze-thaw-refreeze cycles that make driving more dangerous. Freezing rain, which requires both warm and cold air to form, could also increase in frequency. Variability also means that autonomous vehicles will need to navigate these conditions even in presumed-mild climates such as Georgia.
Snow and ice throw a couple of wrenches at autonomous vehicles. Cars need to be taught how to brake or slow down on slush, soft snow, packed snow, melting snow, ice — every variation of winter road condition. Other drivers and pedestrians also behave differently in snow than in clear weather, which machine learning models must incorporate. The car itself will also behave differently, with traction changing at critical moments, such as when approaching an intersection or crosswalk.
Expanding the datasets (or “experience”) of autonomous vehicles will help solve the problem on the technological side. But reduced sensor accuracy remains a big concern — because you can only react to hazards you can identify in the first place. A crust of ice over a camera or lidar sensor can prevent the equipment from working properly, which is a scary thought when no one’s in the driver’s seat.
As Waslander alluded to, there are a few obvious coping mechanisms for robotaxi and autonomous vehicle makers: You can defrost, thaw, wipe, or apply a coating to a sensor to keep it clear. Or you can choose something altogether different.
Recently, a fourth kind of sensor has entered the market. At CES in January, the company Teradar demonstrated its Summit sensor, which operates in the terahertz band of the electromagnetic spectrum, a “Goldilocks” zone between the visible light used by cameras and the human eye and radar. “We have all the advantages of radar combined with all the advantages of lidar or camera,” Gunnar Juergens, the SVP of product at Teradar, told me. “It means we get into very high resolution, and we have a very high robustness against any weather influence.”
The company, which raised $150 million in a Series B funding round last year, says it is in talks with top U.S. and European automakers, with the goal of making it onto a 2028 model vehicle; Juergens also told me the company imagines possible applications in the defense, agriculture, and health-care spaces. Waslander hadn’t heard of Teradar before I told him about it, but called the technology a “super neat idea” that could prove to be a “really useful sensor” if it is indeed able to capture the advantages of both radar and lidar. “You could imagine replacing both with one unit,” he said.
Still, radar and lidar are well-established technologies with decades of development behind them, and “there’s a reason” automakers rely on them, Waslander told me. Using the terahertz band, “there’s got to be some trade-offs,” he speculated, such as lower measurement accuracy or higher absorption rates. In other words, while Teradar boasts the upsides of both radar and lidar, it may come with some of their downsides, too.
Another point in Teradar’s favor is that it doesn’t use a lens at all — there’s nothing to fog, freeze, or salt over. The sensor could help address a fundamental assumption of autonomy — as Juergen put it, “if you transfer responsibility from the human to a machine, it must be better than a human.” There are “very good solutions on the road,” he went on. “The question is, can they handle every weather or every use case? And the answer is no, they cannot.” Until sensors can demonstrate matching or exceeding human performance in snowy conditions — whether through a combination of lidar, cameras, and radar, or through a new technology such as Teradar’s Summit sensor — this will remain true.
If driving in winter weather can eventually be automated at scale, it could theoretically save thousands of lives. Until then, you might still consider using that empty parking lot nearby to brush up on your brake pumping.
Otherwise, there’s always Phoenix; I’ve heard it’s pleasant this time of year.