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Truckers have to transport massive loads long distances, every single day, under intense time pressure—and they rely on the semi-trucks they drive to get the job done. Their diesel engines spew not only greenhouse gas emissions that cause climate change, but also nitrogen oxide, which can be extremely harmful for human health.

Cleaning up trucking, especially the biggest trucks, presents a massive challenge. That’s why some companies are trying to ease the industry into change. For my most recent story, I took a look at Range Energy, a startup that’s adding batteries to the trailers of semi-trucks. If the electrified trailers are attached to diesel trucks, they can improve the fuel economy. If they’re added to zero-emissions vehicles powered by batteries or hydrogen, they could boost range and efficiency.

During my reporting, I learned more about what’s holding back progress in trucking and how experts are thinking about a few different technologies that could help.

The entire transportation sector is slowly shifting toward electrification: EVs are hitting the road in increasing numbers, making up 18% of sales of new passenger vehicles in 2023.

Trucks may very well follow suit—nearly 350 models of zero-emissions medium- and heavy-duty trucks are already available worldwide, according to data from CALSTART. “I do see a lot of strength and demand in the battery electric space in particular,” says Stephanie Ly, senior manager for e-mobility strategy and manufacturing engagement at the World Resources Institute.

But battery-powered trucks will pose a few major challenges as they take to the roads. First, and perhaps most crucially, is their cost. Battery-powered trucks, especially big models like semi-trucks, will be significantly more expensive than diesel versions today.

There may be good news on this front: When you consider the cost of refueling and maintenance, it’s looking like electric trucks could soon compete with diesel. By 2030, the total cost of ownership of a battery electric long-haul truck will likely be lower than that of a diesel one in the US, according to a 2023 report from the International Council on Clean Transportation. The report looked at a number of states including California, Georgia, and New York, and found that the relatively high upfront cost for electric trucks are balanced out by lower operating expenses.

Another significant challenge for battery-powered trucking is weight: The larger the vehicle, the bigger the battery. That could be a problem given current regulations, which typically limit the weight of a rig both for safety reasons and to prevent wear and tear on roads (in the US, it’s 80,000 pounds). Operators tend to want to maximize the amount of goods they can carry in each load, so the added weight of a battery might not be welcome.

Finally, there’s the question of how far trucks can go, and how often they’ll need to stop. Time is money for truck drivers and fleet operators. Batteries will need to pack more energy into a smaller space so that trucks can have a long enough range to run their routes. Charging is another huge piece here—if drivers do need to stop to charge their trucks, they’ll need much more powerful chargers to enable them to top off quickly. That could present challenges for the grid, and operators might need to upgrade infrastructure in certain places to allow the huge amounts of power that would be needed for fast charging of massive batteries.

All these challenges for battery electric trucks add up. “What companies are really looking for is something they can swap out,” says Thomas Walker, transportation technology manager at the Clean Air Task Force. And right now, he says, we’re just not quite in a spot where batteries are a clean and obvious switch.

That’s why some experts say we should keep our options open when it comes to technologies for future heavy-duty trucks, and that includes hydrogen.

Batteries are currently beating out hydrogen in the race to clean up transportation, as I covered in a story earlier this year. For most vehicles and most people, batteries simply make more sense than hydrogen, for reasons that include everything from available infrastructure to fueling cost.

But heavy-duty trucks are a different beast: Heavier vehicles, bigger batteries, higher power charging, and longer distances might tip the balance in favor of hydrogen. (There are some big “ifs” here, including whether hydrogen prices will get low enough to make hydrogen-powered vehicles economical.)

For a sector as tough to decarbonize as heavy-duty trucking, we need all the help we can get. As Walker puts it, “It’s key that you start off with a lot of options and then narrow it down, rather than trying to pick which one’s going to win, because we really don’t know.”

Now read the rest of The Spark

Two more things

Spotting wildfires early and keeping track of them can be tough. Now one company wants to monitor blazes using high-altitude balloons. Next month in Colorado, Urban Sky is deploying balloons that are about as big as vans, and they’ll be keeping watch using much finer resolution than what’s possible with satellites without a human pilot. Read more about fire-tracking balloons in this story from Sarah Scoles.

A new forecasting model attempts to marry conventional techniques with AI to better predict the weather. The model from Google uses physics to work out larger atmospheric forces, then tags in AI for the smaller stuff. Check out the details in the latest from my colleague James O’Donnell.

Keeping up with climate

Small rocky nodules in the deep sea might be a previously undiscovered source of oxygen. They contain metals such as lithium and are a potential target for deep-sea mining efforts. (Nature)

→ Polymetallic nodules are roughly the size and shape of potatoes, and they may be the future of mining for renewable energy. (MIT Technology Review)

A 350-foot-long blade from a wind turbine off the coast of Massachusetts broke off last week, and hunks of fiberglass have been washing up on local beaches. The incident is a setback for a struggling offshore wind industry, and we’re still not entirely sure what happened. (Heatmap News)

A new report shows that low-emissions steel- and iron-making processes are on the rise. But coal-powered operations are still growing too, threatening progress in the industry. (Canary Media)

Sunday, July 21, was likely the world’s hottest day in recorded history (so far). It edged out a record set just last year. (The Guardian)

Plastic forks, cups, and single-use packages are sometimes stamped with nice-sounding labels like “compostable,” “biodegradable,” or just “Earth-friendly.” But that doesn’t mean you can stick the items in your backyard compost pile—these marketing terms are basically the Wild West. (Washington Post)

While EVs are indisputably better than gas-powered cars in terms of climate emissions, they are heavier, meaning they wear through tires faster. The resulting particulate pollution presents a new challenge, one a startup company is trying to address with new tires designed for electric vehicles. (Canary Media)

Public fast chargers are popping up nearly everywhere in the US—at this pace, they’ll outnumber gas stations by 2030. And deployment is only expected to speed up. (Bloomberg)