Viktor MusilHydrogen-Powered Buses: A Bold Bet on Green Transportation in Santa Cruz County
The Santa Cruz Metro governing board placed a significant wager on the future of green public transportation in September when it approved the purchase of 57 hydrogen-powered buses, the largest order of such buses to be produced in the United States to date.
The single tailpipe emissions from the brand-new cars, which could be available as early as the end of 2024, are water. The majority of the authority’s outdated buses, which use compressed normal gas, will be replaced by them.
There is only one issue: The majority of the hydrogen that is already accessible comes from fossil fuels, which increases the amount of greenhouse gas emissions that hydrogen buses are supposed to cut down on. The fuel won’t be truly “green” until hydrogen can be produced by splitting water into hydrogen and oxygen using electricity produced from clean sources like solar and wind. Santa Cruz Metro is betting on technology that isn’t but widely accessible as a result.
Michael Tree, CEO of Santa Cruz Metro, said,” I have a complete recognition that it is not perfect.” ” We took a small chance.”
Transit agencies across the state must switch all of their fleets to buses with zero tailpipe emissions by 2040 in accordance with regulations established by the California Air Resources Board. However, they are planning distinct routes to get it across the Bay Area and the Central Coast, with the majority spending more money on battery-electric buses than hydrogen.
For instance, San Francisco Muni now operates more than 550 cross diesel-electric buses, nearly 280 electric trolley buses powered by overhead cables, and only 10 battery-powered vehicles. It intends to phase out hybrid vehicles and switch them all out for battery-powered trolley buses. However, hydrogen buses are not included in Muni’s plans. The Napa Valley Transportation Authority, Marin Transit, and Sonoma County Transit are all considering switching to fully battery-electric fleets.
Different businesses are placing bets. The other major in the area, AC Transit, operates just seven battery-electric models and 23 hydrogen buses in Alameda and Contra Costa counties. Over the ensuing years, it will phase out its more than 550 diesel buses and replace them with a mingled fleet, adding at least two hydrogen buses to each battery-powered bus. Similar plans are being made by SamTrans, which serves San Mateo County, for a hydrogen-dominated mingled fleet.
Santa Cruz Metro stands out for going all-in on hydrogen in proportion to this. Additionally, it has made an early commitment to the technology by then placing a sizable order for hydrogen buses. “We have a tendency to be very creative, forward-thinking, and at the forefront.” Shebreh Kalantari-Jones, the chair of the Santa Cruz Metro Board, said,” We are strong in our response because we see the urgency of a problem.”
Infrastructure Challenges and Technological Considerations: Factors Shaping Zero-Emission Buses Adoption
The selection of the appropriate number and type of zero-emission buses depends on a variety of factors, such as the electric grid infrastructure, bus routes, and road type, according to Jack Brouwer, director of UC Irvine’s National Fuel Cell Research Center and Advanced Power and Energy Program. For instance, battery-powered buses use more energy on steep roads. Although San Francisco Muni saw no issue with battery-electric buses ascending the city’s peaks, Santa Cruz Metro was concerned about that given its existing routes. Marley Miller, an associate engineer for San Francisco Muni, wrote in an email,” Our battery buses have been tested on rocky hills and can handle any route that our cross buses would be assigned to.”
Kalantari-Jones recognizes additional benefits of hydrogen buses. Each bus can be fueled in less than 15 minutes before being prepared for a 350-mile drive, whereas it can take up to eight hours to fully charge for one of the many shorter ranges—up to 200 miles. Additionally, hydrogen buses weigh on 11, 000 pounds less, making them easier to use on the roads in Santa Cruz County. However, given that really clean hydrogen fuel is not yet accessible, some experts are still not persuaded by the plan.
Ray Minjares, director of the International Council on Clean Transportation’s heavy-duty vehicles program, said,” It puts the cart before the horse.” He declared,” We won’t decarbonize our transportation industry based on fossil hydrogen.”
Electric motors are used in hydrogen buses. Fuel cells combine hydrogen and oxygen from the air to produce water and electricity. Presently, buses like those run by AC Transit are powered by hydrogen fuel, which is created by a process known as steam-methane reforming, in which natural gas is transformed into carbon dioxide and hydrogen in the presence of heat and catalyst. The name of this fuel is “gray” hydrogen. The carbon dioxide-equivalent greenhouse gas emissions from producing gray hydrogen are more than 25 % higher than those from burning natural gas for heat, according to a 2021 study.
Santa Cruz Metro does not currently have access to truly natural hydrogen or hydrogen fueling stations. However, on November 3, the Biden Administration gave$ 1.2 billion to a public-private partnership called ARCHES, the Alliance for Renewable Clean Hydrogen Energy System, to aid in the construction of California’s clean hydrogen hub. Industry is expected to invest about$ 9 billion, and the state government is providing an additional$ 2 billion. Santa Cruz Metro anticipates this to be a game-changer. The board’s decision to place its significant bet on hydrogen buses was announced by Tree as” the word on the street was that ARCHES was going to get funded.” The hub will invest in infrastructure over the course of the following eight years, including pipelines for distributing liquefied hydrogen throughout the state, fueling stations, and facilities for hydrogen production. Importantly, it uses solar electricity from sources like solar, wind, and biomass to produce hydrogen by electrolyzing water into hydrogen and oxygen.
The Path to Truly Clean Hydrogen: Challenges and Opportunities in Zero-Emission Bus Deployment
Given the current mix of fuels used to produce power, buses powered by black hydrogen have more than double the overall emissions of battery-electric buses, according to a report from the International Council on Clean Transportation from February 2023. However, a bus powered by natural hydrogen would emit roughly half as much carbon dioxide as an average battery-operated bus operating on an alternate grid. However, the price of producing clean hydrogen will need to decrease if Santa Cruz Metro’s wager is successful. Methane is used to make gray hydrogen, which costs about$ 2 per kilogram, or 90 cents per pound. However, it currently costs between$ 9 and$ 12 per kilogram ($ 4.10 to$ 5.40 per pound ) to produce green hydrogen through electrolysis. Additionally, it would have to cost roughly the same as producing white hydrogen for green hydrogen buses to be as cost-effective as battery-electric models.
According to Tree, Santa Cruz Metro now has an operating budget of$ 16 million, of which$ 4 million is set aside for fueling expenses. That isn’t going to last for very long. Long-term, he said,” It would be difficult to be paying nine bucks per kilogram.” Tree is certain that the investment in a hydrogen hub will reduce the price. However, Mark Jacobson, a Stanford University climate engineer, thinks that hydrogen buses will never be able to compete because battery-based electricity storage is essentially more energy-efficient. He explained that “we’re going from electricity to producing hydrogen, and then returning the hydrogen again to electricity.” Although it isn’t very effective, you can make it clean.
