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For most US drivers, EVs offer emissions benefits and cost savings

Despite regional variability in climate, electricity sources, congestion, and the wide variation in individual driving patterns, electric vehicles generate less greenhouse gas emissions and do not cost more than comparable gas-powered vehicles for drivers and vehicle fleet owners in most parts of the United States, according to a new study by MIT researchers.

The team’s approach captures many key factors that contribute to regional and individual differences in the life-cycle emissions and ownership cost of electric vehicles, including meteorological data, the distance and duration of trips, and fuel prices.

To paint a fuller picture of emissions and costs than was previously available, the researchers sourced data from thousands of U.S. zip codes and drilled down to the level of individual drivers within those locations. Their study considers time-averaged fuel prices so as not to be overly influenced by fluctuations in prices at any one point in time. They finalized their analysis at the end of 2024 and early 2025.

Their results indicate that a person’s driving behaviors can matter as much as regional factors like the local electricity mix when it comes to the emissions savings of an electric vehicle, compared to a similar gas-powered vehicle. In most locations, a battery-electric vehicle reduces emissions between 40 and 60 percent, with larger impacts in urban areas. 

They also found that colder climates do not reduce overall emission benefits as much as some media reports assume.

The researchers utilized this detailed analysis to update a public tool they previously developed, carboncounter.com, which enables individuals to compare the life-cycle emissions and total ownership costs of nearly any car on the market. A new version of carboncounter.com is also being released today.

“There are a lot of statements being thrown around, like that electric vehicles don’t reduce emissions very much in cool climates, and we wanted to analyze these factors systematically and evaluate these statements against one another simultaneously. Rather than simply asking, ‘Are EVs better?’, this paper helps answer ‘better for whom, and under what conditions?’” says Marco Miotti PhD ’20, a senior researcher at ETH Zurich who completed this research while a graduate student in the Institute for Data, Systems, and Society (IDSS) at MIT. 

He is joined on the paper by senior author Jessika Trancik, a professor in IDSS. The research appears today in Environmental Research Letters.

A holistic approach

Many prior studies that compare emissions and costs of electric vehicles (EVs) to combustion-engine vehicles cover a few factors, like the amount of renewable energy in the grid and how gas prices impact affordability, Miotti says.

“To our knowledge, there have been few efforts so far that bring all these factors together. But if someone wants to buy a car and have a better understanding of the factors that affect emissions and costs, this holistic approach is important,” he adds.

The researchers focused on two types of EVs: battery-electric vehicles, which only operate on electricity, and plug-in hybrid electric vehicles, which also have a combustion engine that works in tandem with the battery to optimize fuel savings.

The team expanded and improved a set of previously developed vehicle cost and emissions models to incorporate a wider variety of factors and data types.

For instance, they refined an existing model that estimates energy use and gas mileage so it could capture more nuances of local climate variability. 

“But the real effort was not just in extending these different models, but in bringing together all these different data and making them work with the models in a consistent manner,” Miotti says.

The team sourced data on a wide variety of factors for each U.S. zip code, such as typical drive cycles, the amount of traffic, local gas and electricity prices, makeup of the regional electricity mix, meteorological profiles, and more. They used statistical approaches to amalgamate different types of data. 

For example, the team used a probabilistic matching technique to combine data on how often people drive, which was drawn from nationwide travel surveys, with more detailed GPS data that includes factors like drivers’ acceleration patterns and the distance they usually drive on each day of the week.

The researchers designed their analysis to focus on the spatial picture of emissions and costs, based on U.S. zip codes, while simultaneously considering the impact of the size and features of each specific vehicle model.

“At the end of the day, it’s the vehicle and fleet owners who make decisions about vehicle purchases. So, we wanted to make sure to consider their wide-ranging individual perspectives rather than simply performing a region-by-region comparison,” says Trancik.

Lower emissions, comparable costs

In the end, their modeling framework revealed that all factors they analyzed matter about equally in determining emissions-reduction potential of EVs compared to internal combustion vehicles. 

EVs reduce emissions the most in areas with a cleaner electricity mix, denser traffic, higher annual travel distances, and a mild climate, in decreasing order of importance. In each area, emission reductions increase for drivers who drive more often, drive larger vehicles, and are more frequently stuck in traffic. 

In a colder area like North Dakota, fuel economy of battery-electric vehicles might be reduced by as much as 50 percent on a particularly frigid night, but the effect on annual emission benefits is minimal. 

“We even did a sensitivity study to see if the range is reduced in very cold climates, and we found that, even in the most unfavorable conditions, EVs still reduce emissions by a substantial amount,” Miotti says.

On the cost side, the models show that, in most places across the U.S., EVs are competitive with comparable combustion-engine vehicles in terms of lifetime ownership cost, even without clean vehicle tax credits. And in areas where electricity is relatively affordable, battery-electric vehicles tend to cost less than their plug-in hybrid or combustion-engine counterparts.

In the future, the researchers want to expand this analysis to include a temporal dimension, so the framework also considers how changes in vehicle, fuel, and electricity prices affect emissions and costs over time. 

“While we found that the electricity mix is a big driver of the spatial variation in emissions savings of EVs, the electricity grid is decarbonizing everywhere. As that happens, emissions savings across space will become more homogenous for EVs, but the differences across one driver to another will remain,” Miotti says.

They could also use the framework to explore regions outside the United States or incorporate data on hybrid-electric vehicles that cannot be plugged in.

This work was funded, in part, by the MIT Martin Family Society of Fellows for Sustainability.

© Credit: iStock

A new MIT study finds that despite regional differences in climate, electricity sources, traffic, and driving patterns, electric vehicles produce fewer greenhouse gas emissions — and cost no more to own — than comparable gas-powered cars for most U.S drivers.

Tighter 2027 EPA NOx Rules Put Fleets on the Clock

By: Ryan Gray
5 May 2026 at 15:52

LAS VEGAS — The Trump administration may have the revoked greenhouse gas (GHG) rules, but student transportation fleets are still barreling toward a major emissions change that will reshape diesel engine technology, maintenance practices and purchasing strategies as soon as Jan. 1, 2027.

That was the clear message from engine and truck executives during Monday’s ACT Expo roundtable, “What the Final Rule Means for Fleets, OEMs & Suppliers.” Cummins and International leaders urged fleets to prepare now for the new low nitrogen oxides (NOx) rules — and not be lulled into complacency by headlines regarding greenhouse gas (GHG) rollbacks.

GHG Push Eases, but NOx Crackdown is Full Speed Ahead

David Hillman, vice president of integrated technology sales at IC Bus parent company International, told attendees that many fleets still misunderstand the regulatory landscape. He said fleets often assume that because federal GHG actions were rescinded, tailpipe rules are off the table. That, he warned, is wrong.

He urged fleets to separate climate-focused GHG policy from criteria pollutant rules such as NOx. The federal GHG “endangerment” framework — which effectively pushed manufacturers toward battery-electric vehicles by requiring rapid fuel-efficiency gains — has been set aside.

But the EPA’s low-NOx rule remains, added panelist Andrea Lukas, the director of product management for the North American on-highway business at Cummins

“We’ve heard from high-level officials at EPA that’s sticking, so we need to prepare for that now,” she said.

The upcoming federal standard will tighten heavy-duty NOx limits to 35 milligrams, or 0.035 g/bhp-hr, starting Jan. 1. Hillman described the change as an approximately 80 percent reduction in NOx compared with current levels. That shift is substantial, even though the core diesel technology path of diesel oxidation catalysts, diesel particulate filters and selective catalyst reduction aftertreatment will remain largely familiar.

For school buses, that means diesel is not going away anytime soon, but the next generation of engines will be more complex, more tightly controlled and, almost certainly, more expensive.

“Speaking for International, we’ve been fairly direct that we are we’re very bullish on diesel … it’s hard to beat the efficiency of the diesel combustion cycle … diesel’s got a very enviable track record in position,” Hillman added. “I think it’s reasonable to expect diesel efficiency to still be applicable into the 2040 and beyond realm.”

Costs Less Than Early Numbers but Still Higher

A year to 18 months ago and even at the STN EXPO East conference in March, many fleets heard dire projections about price spikes for 2027-compliant vehicles. Hillman explained those early figures assumed not only new hardware but also much longer federal emission warranty and “useful life” requirements — in some proposals, up to 10 years.

He said roughly half of the anticipated price increase was tied to added hardware and design changes, while the other half came from extended emission warranties and the costly validation work to ensure engines would still meet the 35 mg NOx limit a decade after production.

More recent signals from EPA suggest warranty and useful-life requirements may revert closer to today’s norms, such as five years or 100,000 miles in the heavy-duty space. If that holds in the final rule, Hillman said fleets can roughly “cut in half” some of the largest price increases they heard discussed last year.

Still, the technology required to hit 35 mg NOx rule has its costs. Student transportation directors should budget for higher acquisition costs for 2027 and newer diesel buses, even if the final price tags fall short of the early worst-case scenarios. Exact numbers will not be clear until the EPA’s rulemaking language is finalized.

Fuel, DEF and Performance: Less Disruption than 2007, 2010

On performance, both Cummins and International stressed that fleets should not expect the kind of fuel-economy and drivability disruptions seen in the 2007 and 2010 emission changeovers.

Lukas said the focus is now building on mature architectures rather than introducing unproven concepts. Larger catalysts, new heating strategies to address cold-start NOx, and packaging changes are being paired with redesigned, lighter engine blocks and combustion improvements.

Lukas said Cummins is targeting fuel efficiency improvements on its new platforms and weight neutrality once lighter engine components and larger aftertreatment systems are balanced. She also said the company aims to keep diesel exhaust fluid (DEF) consumption in a similar range to today’s levels.

“We are utilizing a belt‑driven alternator, so pretty simple technology on the engine, and so that powers heaters in the aftertreatment … trying to simplify it as much as possible by using known designs,” she explained.

Hillman said International’s S13 powertrain is engineered to be fuel-economy neutral and weight neutral with the 2027 regulations in most applications. He expects DEF consumption to rise modestly — on the order of one percentage point relative to fuel, rather than a dramatic jump.

For school buses, that could mean routing, refueling infrastructure and gross vehicle weight ratings may not require wholesale redesigns. Instead, DEF logistics and range assumptions should be revisited once final product specifications are known.

Emissions Training and Tools

One message that came through clearly for maintenance managers: Training cannot wait.

Lukas said Cummins will begin rolling out technician training for 2027 products over the next one to two months, with materials pushed through OEM and dealer channels. She urged fleets to take every available opportunity to get technicians trained early, especially around new service tools.

For fleets running Cummins-powered trucks and buses, one major shift will be the retirement of Cummins Insight on the model-year 2027 and beyond fuel-agnostic HELM platforms. Instead, Cummins will rely on Guidanz as its primary diagnostic and service interface, with expanded digital capabilities, including portals, over-the-air diagnostics and remote calibration updates.

International, which carries over roughly 90 percent of the hardware in its S13 powertrain from current products, expects less disruption in its own toolchain. But Hillman echoed Lukas on the need for ongoing technician and driver training to keep pace with more sophisticated electronics and emissions controls.

Don’t Wait on Pre-Buys

Hillman and Lukas also warned that the back half of 2026 is likely to be production-constrained, as fleets across multiple sectors pull forward purchases to avoid first-year 2027 NOx rule pricing and complexity. This year’s State of Sustainable Fleets report unveiled Monday at ACT Expo stated that manufacturers are already selling out new build slots for the third and fourth quarters of 2026.

While the panelists said they do not expect a pre-buy on the scale of 2007 or 2010, both Cummins and International anticipate enough “front-loading” of demand to stress supplier capacity. In practice, that means school bus orders for the 2026–2027 school year could compete with a crowded market, especially for certain configurations.

Article written with the assistance of AI session transcript.


Related: Updated: EPA Seeks to Expand Fuel Scope of Clean School Bus Program
Related: Amid ‘Unprecedented Degree of Uncertainty,’ CARB Proposes Two Pathways for Emissions Regulations
Related: Micro Bird Officially Opens U.S. Manufacturing, School Bus Production Already Underway

The post Tighter 2027 EPA NOx Rules Put Fleets on the Clock appeared first on School Transportation News.

Zonar Becomes First Telematics Provider Approved for OEM-Based California Air Resources Board Clean Truck Check Compliance

By: STN
26 February 2026 at 21:06

SEATTLE, Wash. — Zonar, a leader in smart fleet management and compliance solutions, today announced it has become the first telematics provider certified by the California Air Resources Board (CARB) to support Clean Truck Check (CTC) compliance through OEM-installed vehicle integrations. With 14+ years of the Zonar V4 telematics box installed on approximately 400,000 Freightliner Cascadia, Thomas Built Buses, and Western Star trucks at the factory, any fleet operating these vehicles in California today can immediately access the solution.

A first in the industry, this expanded executive order allows fleets operating California CTC-regulated vehicles to meet emissions compliance requirements without physically connecting to the vehicle’s diagnostic port or installing additional aftermarket hardware.

Why Zonar’s CARB Emission Solution Is Different

CARB’s Clean Truck Check regulation requires non-gasoline vehicles over 14,000 lbs operating in California to submit emissions data on a recurring schedule. Until now, compliance typically required:

Manual scans at a shop or yard.

Third-party service providers.

Vehicle downtime and scheduling complexity.

Zonar’s newly approved certification introduces a new compliance pathway.

With this executive order, OEM-installed and hardwired Zonar devices, already embedded in supported vehicles, can automatically collect and submit required emissions data directly to CARB. No shop visits. No plug-in scans. No operational disruption.

Zonar is the only provider whose CARB executive order explicitly permits compliance via a hardwired vehicle harness, not just a direct OBD connection.

Who This Impacts

With large and distributed fleets facing increasing compliance frequency, moving to four checks per year beginning in 2027, this certification directly benefits:

Fleets operating in California subject to CARB Clean Truck Check requirements.

OEM-equipped vehicles, including factory-installed telematics configurations.

School transportation, transit, and commercial fleets seeking to reduce downtime and compliance risk.

Mixed and transitioning fleets, where OEM-equipped vehicles can now meet compliance requirements without operational inconsistency.

Fleets can now achieve CARB compliance automatically, in the background, using hardware already installed in their vehicles, either as a standalone emissions solution or alongside Zonar’s broader telematics, diagnostics, and maintenance offerings.

First to Market Again
Zonar was the first telematics provider certified by CARB as a continuously connected Clean Truck Check solution and is now the first, and only, provider approved for OEM-installed and hardwired configurations.

This milestone reflects years of close collaboration with CARB, OEM partners, and Zonar’s in-house engineering team to meet the most rigorous regulatory and technical standards.

“CARB compliance is becoming more frequent, more complex, and more disruptive for fleets—but it doesn’t have to be,” said Amit Anand, SVP of Product at Zonar. “Because we design our own hardware, work directly with OEMs, and partner closely with CARB, we were able to deliver a solution no one else in the market could. This certification removes downtime, eliminates guesswork, and allows fleets to stay compliant automatically using technology they already have.”

Why Zonar’s OEM-Certified CARB Emission Solution Changes the Experience for Fleets

With Zonar’s Emission Check, fleets experience:

No downtime for compliance scans.
Earlier detection of emissions issues within CARB’s compliance window.

Lower cost compared to manual or third-party scans.

Future-readiness as CARB enforcement and inspection frequency increases.

With enforcement tied to vehicle registration, roadside inspections, ports, and rail yards, CARB compliance is no longer optional. Zonar’s solution helps fleets meet these requirements proactively and seamlessly, reducing risk while keeping vehicles on the road.

To learn more about the CARB Clean Truck Emissions Check, go to https://www.zonarsystems.com/solutions/carb-clean-truck-emissions-check/.

About Zonar Systems:
Zonar combines a unified fleet management platform with reliable telematics hardware and always-on human support giving mission-critical fleets precise, trustworthy data to improve safety, ensure compliance and reduce operating costs. Proven every day in pupil transportation, where it safeguards millions of children, Zonar’s technology and partnership deliver the trust, transparency and confidence public-sector, field service and vocational fleets need to perform when it matters most. To learn more, go to www.zonarsystems.com.

The post Zonar Becomes First Telematics Provider Approved for OEM-Based California Air Resources Board Clean Truck Check Compliance appeared first on School Transportation News.

Study shows making hydrogen with soda cans and seawater is scalable and sustainable

Hydrogen has the potential to be a climate-friendly fuel since it doesn’t release carbon dioxide when used as an energy source. Currently, however, most methods for producing hydrogen involve fossil fuels, making hydrogen less of a “green” fuel over its entire life cycle.

A new process developed by MIT engineers could significantly shrink the carbon footprint associated with making hydrogen.

Last year, the team reported that they could produce hydrogen gas by combining seawater, recycled soda cans, and caffeine. The question then was whether the benchtop process could be applied at an industrial scale, and at what environmental cost.

Now, the researchers have carried out a “cradle-to-grave” life cycle assessment, taking into account every step in the process at an industrial scale. For instance, the team calculated the carbon emissions associated with acquiring and processing aluminum, reacting it with seawater to produce hydrogen, and transporting the fuel to gas stations, where drivers could tap into hydrogen tanks to power engines or fuel cell cars. They found that, from end to end, the new process could generate a fraction of the carbon emissions that is associated with conventional hydrogen production.

In a study appearing today in Cell Reports Sustainability, the team reports that for every kilogram of hydrogen produced, the process would generate 1.45 kilograms of carbon dioxide over its entire life cycle. In comparison, fossil-fuel-based processes emit 11 kilograms of carbon dioxide per kilogram of hydrogen generated.

The low-carbon footprint is on par with other proposed “green hydrogen” technologies, such as those powered by solar and wind energy.

“We’re in the ballpark of green hydrogen,” says lead author Aly Kombargi PhD ’25, who graduated this spring from MIT with a doctorate in mechanical engineering. “This work highlights aluminum’s potential as a clean energy source and offers a scalable pathway for low-emission hydrogen deployment in transportation and remote energy systems.”

The study’s MIT co-authors are Brooke Bao, Enoch Ellis, and professor of mechanical engineering Douglas Hart.

Gas bubble

Dropping an aluminum can in water won’t normally cause much of a chemical reaction. That’s because when aluminum is exposed to oxygen, it instantly forms a shield-like layer. Without this layer, aluminum exists in its pure form and can readily react when mixed with water. The reaction that occurs involves aluminum atoms that efficiently break up molecules of water, producing aluminum oxide and pure hydrogen. And it doesn’t take much of the metal to bubble up a significant amount of the gas.

“One of the main benefits of using aluminum is the energy density per unit volume,” Kombargi says. “With a very small amount of aluminum fuel, you can conceivably supply much of the power for a hydrogen-fueled vehicle.”

Last year, he and Hart developed a recipe for aluminum-based hydrogen production. They found they could puncture aluminum’s natural shield by treating it with a small amount of gallium-indium, which is a rare-metal alloy that effectively scrubs aluminum into its pure form. The researchers then mixed pellets of pure aluminum with seawater and observed that the reaction produced pure hydrogen. What’s more, the salt in the water helped to precipitate gallium-indium, which the team could subsequently recover and reuse to generate more hydrogen, in a cost-saving, sustainable cycle.

“We were explaining the science of this process in conferences, and the questions we would get were, ‘How much does this cost?’ and, ‘What’s its carbon footprint?’” Kombargi says. “So we wanted to look at the process in a comprehensive way.”

A sustainable cycle

For their new study, Kombargi and his colleagues carried out a life cycle assessment to estimate the environmental impact of aluminum-based hydrogen production, at every step of the process, from sourcing the aluminum to transporting the hydrogen after production. They set out to calculate the amount of carbon associated with generating 1 kilogram of hydrogen — an amount that they chose as a practical, consumer-level illustration.

“With a hydrogen fuel cell car using 1 kilogram of hydrogen, you can go between 60 to 100 kilometers, depending on the efficiency of the fuel cell,” Kombargi notes.

They performed the analysis using Earthster — an online life cycle assessment tool that draws data from a large repository of products and processes and their associated carbon emissions. The team considered a number of scenarios to produce hydrogen using aluminum, from starting with “primary” aluminum mined from the Earth, versus “secondary” aluminum that is recycled from soda cans and other products, and using various methods to transport the aluminum and hydrogen.

After running life cycle assessments for about a dozen scenarios, the team identified one scenario with the lowest carbon footprint. This scenario centers on recycled aluminum — a source that saves a significant amount of emissions compared with mining aluminum — and seawater — a natural resource that also saves money by recovering gallium-indium. They found that this scenario, from start to finish, would generate about 1.45 kilograms of carbon dioxide for every kilogram of hydrogen produced. The cost of the fuel produced, they calculated, would be about $9 per kilogram, which is comparable to the price of hydrogen that would be generated with other green technologies such as wind and solar energy.

The researchers envision that if the low-carbon process were ramped up to a commercial scale, it would look something like this: The production chain would start with scrap aluminum sourced from a recycling center. The aluminum would be shredded into pellets and treated with gallium-indium. Then, drivers could transport the pretreated pellets as aluminum “fuel,” rather than directly transporting hydrogen, which is potentially volatile. The pellets would be transported to a fuel station that ideally would be situated near a source of seawater, which could then be mixed with the aluminum, on demand, to produce hydrogen. A consumer could then directly pump the gas into a car with either an internal combustion engine or a fuel cell.

The entire process does produce an aluminum-based byproduct, boehmite, which is a mineral that is commonly used in fabricating semiconductors, electronic elements, and a number of industrial products. Kombargi says that if this byproduct were recovered after hydrogen production, it could be sold to manufacturers, further bringing down the cost of the process as a whole.

“There are a lot of things to consider,” Kombargi says. “But the process works, which is the most exciting part. And we show that it can be environmentally sustainable.”

The group is continuing to develop the process. They recently designed a small reactor, about the size of a water bottle, that takes in aluminum pellets and seawater to generate hydrogen, enough to power an electric bike for several hours. They previously demonstrated that the process can produce enough hydrogen to fuel a small car. The team is also exploring underwater applications, and are designing a hydrogen reactor that would take in surrounding seawater to power a small boat or underwater vehicle.

This research was supported, in part, by the MIT Portugal Program.

© Credit: Courtesy of the researchers

MIT engineers have developed a new aluminum-based process to produce hydrogen gas, that they are testing on a variety of applications, including an aluminum-powered electric vehicle, pictured here.

Support for Electric Vehicles

By: newenergy
31 March 2025 at 15:54

New Poll: American Voters Support Federal Investments in Electric Vehicles Broad, Bipartisan Support for EV Investments and Incentives that Lower Costs, Expand Access, and Help the U.S. Beat China in the Race for Auto Manufacturing WASHINGTON, D.C. – A new bipartisan national poll conducted by Meeting Street Insights and Hart Research finds broad public support …

The post Support for Electric Vehicles appeared first on Alternative Energy HQ.

Trump EPA takes aim at Biden emissions regulations

White House under President TrumpThe Trump Administration is looking to roll back stricter emissions standards put in place by the Biden administration covering both light-duty passenger cars and heavy-duty commercial trucks. The EPA said Wednesday in a press release that it was targeting greenhouse-gas emissions standards for model years 2027-2032, as well as rules further...

Tackling the energy revolution, one sector at a time

As a major contributor to global carbon dioxide (CO2) emissions, the transportation sector has immense potential to advance decarbonization. However, a zero-emissions global supply chain requires re-imagining reliance on a heavy-duty trucking industry that emits 810,000 tons of CO2, or 6 percent of the United States’ greenhouse gas emissions, and consumes 29 billion gallons of diesel annually in the U.S. alone.

A new study by MIT researchers, presented at the recent American Society of Mechanical Engineers 2024 International Design Engineering Technical Conferences and Computers and Information in Engineering Conference, quantifies the impact of a zero-emission truck’s design range on its energy storage requirements and operational revenue. The multivariable model outlined in the paper allows fleet owners and operators to better understand the design choices that impact the economic feasibility of battery-electric and hydrogen fuel cell heavy-duty trucks for commercial application, equipping stakeholders to make informed fleet transition decisions.

“The whole issue [of decarbonizing trucking] is like a very big, messy pie. One of the things we can do, from an academic standpoint, is quantify some of those pieces of pie with modeling, based on information and experience we’ve learned from industry stakeholders,” says ZhiYi Liang, PhD student on the renewable hydrogen team at the MIT K. Lisa Yang Global Engineering and Research Center (GEAR) and lead author of the study. Co-authored by Bryony DuPont, visiting scholar at GEAR, and Amos Winter, the Germeshausen Professor in the MIT Department of Mechanical Engineering, the paper elucidates operational and socioeconomic factors that need to be considered in efforts to decarbonize heavy-duty vehicles (HDVs).

Operational and infrastructure challenges

The team’s model shows that a technical challenge lies in the amount of energy that needs to be stored on the truck to meet the range and towing performance needs of commercial trucking applications. Due to the high energy density and low cost of diesel, existing diesel drivetrains remain more competitive than alternative lithium battery-electric vehicle (Li-BEV) and hydrogen fuel-cell-electric vehicle (H2 FCEV) drivetrains. Although Li-BEV drivetrains have the highest energy efficiency of all three, they are limited to short-to-medium range routes (under 500 miles) with low freight capacity, due to the weight and volume of the onboard energy storage needed. In addition, the authors note that existing electric grid infrastructure will need significant upgrades to support large-scale deployment of Li-BEV HDVs.

While the hydrogen-powered drivetrain has a significant weight advantage that enables higher cargo capacity and routes over 750 miles, the current state of hydrogen fuel networks limits economic viability, especially once operational cost and projected revenue are taken into account. Deployment will most likely require government intervention in the form of incentives and subsidies to reduce the price of hydrogen by more than half, as well as continued investment by corporations to ensure a stable supply. Also, as H2-FCEVs are still a relatively new technology, the ongoing design of conformal onboard hydrogen storage systems — one of which is the subject of Liang’s PhD — is crucial to successful adoption into the HDV market.

The current efficiency of diesel systems is a result of technological developments and manufacturing processes established over many decades, a precedent that suggests similar strides can be made with alternative drivetrains. However, interactions with fleet owners, automotive manufacturers, and refueling network providers reveal another major hurdle in the way that each “slice of the pie” is interrelated — issues must be addressed simultaneously because of how they affect each other, from renewable fuel infrastructure to technological readiness and capital cost of new fleets, among other considerations. And first steps into an uncertain future, where no one sector is fully in control of potential outcomes, is inherently risky. 

“Besides infrastructure limitations, we only have prototypes [of alternative HDVs] for fleet operator use, so the cost of procuring them is high, which means there isn’t demand for automakers to build manufacturing lines up to a scale that would make them economical to produce,” says Liang, describing just one step of a vicious cycle that is difficult to disrupt, especially for industry stakeholders trying to be competitive in a free market. 

Quantifying a path to feasibility

“Folks in the industry know that some kind of energy transition needs to happen, but they may not necessarily know for certain what the most viable path forward is,” says Liang. Although there is no singular avenue to zero emissions, the new model provides a way to further quantify and assess at least one slice of pie to aid decision-making.

Other MIT-led efforts aimed at helping industry stakeholders navigate decarbonization include an interactive mapping tool developed by Danika MacDonell, Impact Fellow at the MIT Climate and Sustainability Consortium (MCSC); alongside Florian Allroggen, executive director of MITs Zero Impact Aviation Alliance; and undergraduate researchers Micah Borrero, Helena De Figueiredo Valente, and Brooke Bao. The MCSC’s Geospatial Decision Support Tool supports strategic decision-making for fleet operators by allowing them to visualize regional freight flow densities, costs, emissions, planned and available infrastructure, and relevant regulations and incentives by region.

While current limitations reveal the need for joint problem-solving across sectors, the authors believe that stakeholders are motivated and ready to tackle climate problems together. Once-competing businesses already appear to be embracing a culture shift toward collaboration, with the recent agreement between General Motors and Hyundai to explore “future collaboration across key strategic areas,” including clean energy. 

Liang believes that transitioning the transportation sector to zero emissions is just one part of an “energy revolution” that will require all sectors to work together, because “everything is connected. In order for the whole thing to make sense, we need to consider ourselves part of that pie, and the entire system needs to change,” says Liang. “You can’t make a revolution succeed by yourself.” 

The authors acknowledge the MIT Climate and Sustainability Consortium for connecting them with industry members in the HDV ecosystem; and the MIT K. Lisa Yang Global Engineering and Research Center and MIT Morningside Academy for Design for financial support.

© Photo: Bob Adams/Flickr

A new study by MIT researchers quantifies the impact of a zero-emission truck’s design range on its energy storage requirements and operational revenue.

MIT students combat climate anxiety through extracurricular teams

Climate anxiety affects nearly half of young people aged 16-25. Students like second-year Rachel Mohammed find hope and inspiration through her involvement in innovative climate solutions, working alongside peers who share her determination. “I’ve met so many people at MIT who are dedicated to finding climate solutions in ways that I had never imagined, dreamed of, or heard of. That is what keeps me going, and I’m doing my part,” she says.

Hydrogen-fueled engines

Hydrogen offers the potential for zero or near-zero emissions, with the ability to reduce greenhouse gases and pollution by 29 percent. However, the hydrogen industry faces many challenges related to storage solutions and costs.

Mohammed leads the hydrogen team on MIT’s Electric Vehicle Team (EVT), which is dedicated to harnessing hydrogen power to build a cleaner, more sustainable future. EVT is one of several student-led build teams at the Edgerton Center focused on innovative climate solutions. Since its founding in 1992, the Edgerton Center has been a hub for MIT students to bring their ideas to life.

Hydrogen is mostly used in large vehicles like trucks and planes because it requires a lot of storage space. EVT is building their second iteration of a motorcycle based on what Mohammed calls a “goofy hypothesis” that you can use hydrogen to power a small vehicle. The team employs a hydrogen fuel cell system, which generates electricity by combining hydrogen with oxygen. However, the technology faces challenges, particularly in storage, which EVT is tackling with innovative designs for smaller vehicles.

Presenting at the 2024 World Hydrogen Summit reaffirmed Mohammed’s confidence in this project. “I often encounter skepticism, with people saying it’s not practical. Seeing others actively working on similar initiatives made me realize that we can do it too,” Mohammed says.

The team’s first successful track test last October allowed them to evaluate the real-world performance of their hydrogen-powered motorcycle, marking a crucial step in proving the feasibility and efficiency of their design.

MIT’s Sustainable Engine Team (SET), founded by junior Charles Yong, uses the combustion method to generate energy with hydrogen. This is a promising technology route for high-power-density applications, like aviation, but Yong believes it hasn’t received enough attention. Yong explains, “In the hydrogen power industry, startups choose fuel cell routes instead of combustion because gas turbine industry giants are 50 years ahead. However, these giants are moving very slowly toward hydrogen due to its not-yet-fully-developed infrastructure. Working under the Edgerton Center allows us to take risks and explore advanced tech directions to demonstrate that hydrogen combustion can be readily available.”

Both EVT and SET are publishing their research and providing detailed instructions for anyone interested in replicating their results.

Running on sunshine

The Solar Electric Vehicle Team powers a car built from scratch with 100 percent solar energy.

The team’s single-occupancy car Nimbus won the American Solar Challenge two years in a row. This year, the team pushed boundaries further with Gemini, a multiple-occupancy vehicle that challenges conventional perceptions of solar-powered cars.

Senior Andre Greene explains, “the challenge comes from minimizing how much energy you waste because you work with such little energy. It’s like the equivalent power of a toaster.”

Gemini looks more like a regular car and less like a “spaceship,” as NBC’s 1st Look affectionately called Nimbus. “It more resembles what a fully solar-powered car could look like versus the single-seaters. You don’t see a lot of single-seater cars on the market, so it’s opening people’s minds,” says rising junior Tessa Uviedo, team captain.

All-electric since 2013

The MIT Motorsports team switched to an all-electric powertrain in 2013. Captain Eric Zhou takes inspiration from China, the world’s largest market for electric vehicles. “In China, there is a large government push towards electric, but there are also five or six big companies almost as large as Tesla size, building out these electric vehicles. The competition drives the majority of vehicles in China to become electric.”

The team is also switching to four-wheel drive and regenerative braking next year, which reduces the amount of energy needed to run. “This is more efficient and better for power consumption because the torque from the motors is applied straight to the tires. It’s more efficient than having a rear motor that must transfer torque to both rear tires. Also, you’re taking advantage of all four tires in terms of producing grip, while you can only rely on the back tires in a rear-wheel-drive car,” Zhou says.

Zhou adds that Motorsports wants to help prepare students for the electric vehicle industry. “A large majority of upperclassmen on the team have worked, or are working, at Tesla or Rivian.”

Former Motorsports powertrain lead Levi Gershon ’23, SM ’24 recently founded CRABI Robotics — a fully autonomous marine robotic system designed to conduct in-transit cleaning of marine vessels by removing biofouling, increasing vessels’ fuel efficiency.

An Indigenous approach to sustainable rockets

First Nations Launch, the all-Indigenous student rocket team, recently won the Grand Prize in the 2024 NASA First Nations Launch High-Power Rocket Competition. Using Indigenous methodologies, this team considers the environment in the materials and methods they employ.

“The environmental impact is always something that we consider when we’re making design decisions and operational decisions. We’ve thought about things like biodegradable composites and parachutes,” says rising junior Hailey Polson, team captain. “Aerospace has been a very wasteful industry in the past. There are huge leaps and bounds being made with forward progress in regard to reusable rockets, which is definitely lowering the environmental impact.”

Collecting climate change data with autonomous boats

Arcturus, the recent first-place winner in design at the 16th Annual RoboBoat Competition, is developing autonomous surface vehicles that can greatly aid in marine research. “The ocean is one of our greatest resources to combat climate change; thus, the accessibility of data will help scientists understand climate patterns and predict future trends. This can help people learn how to prepare for potential disasters and how to reduce each of our carbon footprints,” says Arcturus captain and rising junior Amy Shi.

“We are hoping to expand our outreach efforts to incorporate more sustainability-related programs. This can include more interactions with local students to introduce them to how engineering can make a positive impact in the climate space or other similar programs,” Shi says.

Shi emphasizes that hope is a crucial force in the battle against climate change. “There are great steps being taken every day to combat this seemingly impending doom we call the climate crisis. It’s important to not give up hope, because this hope is what’s driving the leaps and bounds of innovation happening in the climate community. The mainstream media mostly reports on the negatives, but the truth is there is a lot of positive climate news every day. Being more intentional about where you seek your climate news can really help subside this feeling of doom about our planet.”

© Photo: Adam Glanzman

Electric Vehicle Team members (from left to right) Anand John, Rachel Mohammed, and Aditya Mehrotra '22, SM '24 monitor their bike’s performance, battery levels, and hydrogen tank levels to estimate the vehicle’s range.
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