California air quality regulators voted unanimously Thursday to require fleet operators to use 100 percent zero-emission shuttles at the state’s largest airports by 2035.

The new regulation adopted by the California Air Resources Board (CARB) applies to public and private operators of the vans and buses that carry travelers between parking facilities, rental car agencies, hotels and airport terminals. The new rules establish three deadlines for fleets to transition to zero-emission fuel cell or battery electric models.

Under the regulation, shuttle fleets at the state’s 13 largest airports are required to be at least 33 percent zero-emission vehicles by the end of 2027, 66 percent ZEVs by the end of 2031, and 100 percent ZEVs by the end of 2035.

“These vehicles put a lot of miles on. And so anything we can do to help reduce emissions is going to be important,” said CARB chair Mary Nichols said at the agency’s February board meeting.

She added, “We've seen technology emerging that's quite workable for this, and some airports, in fact, already converting their fleets to zero-emissions operations.”

Speaking in support of the regulation at this week's hearing, Jimmy O'Dea, a senior vehicles analyst with the Union of Concerned Scientists, noted the potential for the new rules to boost electrification across heavy-duty truck models.

“This regulation is for shuttle buses,” he said, “but all you have to do is look at what a shuttle bus is. You see a ‘Hilton’ logo on a Mercedes Sprinter van and that’s the same vehicle as an Amazon delivery van.”

He went on: “This standard really sets a precedent for manufacturers to start thinking about the vehicles they make, not just for shuttle buses but for the much larger truck sector.”

Transitioning to zero-emission fleets

Zero-emission airport shuttles will replace mostly fossil-fueled models. According to CARB, nearly 80 percent of the existing fleet in California runs on compressed natural gas, with the remaining 20 percent powered by gasoline, propane, diesel and batteries.

In a presentation to the board at its February meeting, CARB air pollution specialist Anthony Poggi said zero-emission shuttles are not only ideally suited for airport duty — operating up to 200 miles a day on short, fixed routes at low speeds — but will, over time, save their owners money.

CARB estimates the transition to zero-emission fleets will save airport shuttle operators a combined $30 million from 2020 to 2040 in avoided fuel and maintenance costs and the use of Low Carbon Fuel Standard credits.

Absent incentives, payback for individual shuttle buses should come in eight years. With incentives, such as those offered under the Hybrid and Zero-Emission Truck and Bus Voucher Incentive Project (HVIP), which provides up to $90,000 toward the purchase of a Class 4 cutaway vehicle, the most commonly used airport shuttle, payback could come in as little as three years.

CARB found that in a head-to-head zero-emission versus compressed natural gas matchup for a Class 4 cutaway shuttle bus purchased in 2027, the ZEV model would save the owner $80,600 over the 12-year life of the vehicle, excluding incentives.

In an email, CARB spokesperson Melanie Turner said the agency is not planning to add airport shuttle-specific incentive programs at this time. But she noted incentives are available to defray the additional upfront cost of zero-emission shuttles today via several CARB incentive programs. Those include HVIP vouchers and ZEV investments resulting from the Volkswagen Environmental Mitigation Trust.

Additional zero-emission vehicle incentives include EV charging infrastructure rebates from California’s investor-owned utilities and grants from the Federal Aviation Administration (FAA) for zero-emission shuttles and charging infrastructure.

Proterra winning orders

According to CARB, 110 zero-emission airport shuttles, equivalent to about 10 percent of the existing in-state fleet, are in use or on order in California.

Nearly one-third of California’s current zero-emission airport shuttle fleet is operated by Wally Park, a private off-airport parking provider serving Los Angeles International Airport. The company’s 33-strong LAX fleet was the nation’s first all-electric airport shuttle fleet.

California is not the only jurisdiction where zero-emission shuttles are gaining traction. This spring, several U.S. airports announced deals to add all-electric buses or EV charging infrastructure.

San Francisco International Airport purchased six all-electric buses and three 60-kilowatt plug-in chargers from Burlingame, California-based Proterra. New York Governor Andrew Cuomo said a new WV charging hub at John F. Kennedy International Airport will include 13 150-kilowatt DC fast-chargers open to the public, ride-hail drivers, taxis, and the airport’s own bus fleets.

San Jose International Airport unveiled a fleet of 10 all-electric Proterra buses partially funded by a $5 million FAA grant. And Charlotte’s Douglas International Airport purchased five e-buses and five 125-kilowatt charging systems from Proterra.

Outside the United States, Amsterdam’s Schiphol Airport and Sydney Airport together have 81 zero-emission shuttles in service or on order, according to CARB.

According to CARB’s Melanie Turner, the zero-emission airport shuttle regulation takes effect on January 1, 2020.

Reporting requirements for shuttle fleet operators begin on January 1, 2022. The next year, a no-backsliding provision ensures that any time a zero-emission shuttle is replaced, the replacement vehicle must also be a ZEV.