IT’S EITHER A climate catastrophe or a climate hero depending on who you ask, but Massachusetts is now dipping its toes in an emerging technology: so-called sustainable aviation fuel (SAF).

A supplemental budget bill that Gov. Maura Healey signed last week includes the state’s first foray into SAF, which is made from cooking oil, plant and animal materials, or synthetic fuel, instead of petroleum. Now on the books is a $10 million tax credit for each of the next three years that’s meant to nudge airlines into adopting the nascent fuel despite opposition from some environmental groups.

The new tax break is in large part thanks to Rich Davey, the CEO of the Massachusetts Port Authority and former state transportation secretary and head of the T, who led the charge for Massachusetts to incentivize uptake of SAF, which some believe can be the answer to the aviation sector’s pollution problem.

Davey led an SAF working group that included other top state officials like Energy and Environmental Affairs Secretary Rebecca Tepper and Healey’s climate chief Melissa Hoffer and urged the governor to implement policies like the tax credit as he pushes for New England to become a SAF hub. The fuel can help cut emissions by around 80 percent, according to both a Harvard study last year and the International Air Transport Association.

“Candidly, this is not just a play about reducing our greenhouse gas emissions, but it’s actually an economic development play,” Davey said in an interview. “One way that states can effectuate policy that actually matters is this tax credit. We just saw this as an opportunity to tell the world through this tax credit that we’re very serious as a state, and so when we brought this to the governor and her team, there was great enthusiasm to get this done.”

Yet even authorizing a pilot program like this is inviting a larger debate about how Massachusetts should weigh the complicated tradeoffs associated with reaching ambitious climate targets, especially for hard-to-decarbonize sectors like air travel.

SAF is a tempting bet for top state officials and lawmakers in Massachusetts, said Chuck Collins, program director at the Institute for Policy Studies, a progressive research and advocacy group. Even though it seems like a no-brainer middle-ground way to appeal to business interests wanting to maintain their commercial operations while cutting the planet-warming emissions their planes spew into the atmosphere, in reality, it’s an expensive alternative that isn’t a “silver bullet,” he said.

The Davey-led SAF working group’s report also found that SAF is about twice as expensive as conventional jet fuel due to a “complex supply chain” of processing, conversion, blending, and other logistics. That’s all the more reason, Davey said, for Massachusetts to join a handful of other states like California, Illinois, and Nebraska in incentivizing its use and augmenting a federal tax credit already in place.

To Collins, though, the cons outweigh the pros. In an October 2025 report on barriers to scaling SAF in Massachusetts he and a co-author found that the fuel doesn’t green the aviation sector at all. If anything, he wrote, SAF increases greenhouse gas emissions because of its electricity demand and potential for increased deforestation to grow crops needed for the fuel.

And displacing current jet fuel use with SAF in Massachusetts alone would require billions of dollars in subsidies in order to quickly incentivize widespread adoption and offset otherwise higher costs for consumers, according to the report.

“Sustainable aviation fuel solves a big short-term PR problem for the airline industry,” Collins said.

The debate over SAF is a microcosm of a larger question around how best to respond to the threats of climate change: Should we try anything and everything to reduce emissions, from SAF to small nuclear reactors to hydrogen, or should we only pursue truly proven technologies that can quickly be deployed?

But for a sector with few other cleaner alternatives, SAF has emerged as the way for airlines to claim progress on climate goals. While SAF currently accounts for less than 1 percent of global jet fuel, the Federal Aviation Administration wants SAF to meet 100 percent of domestic aviation fuel demand by 2050, and production in the US has ramped up.

Investing in SAF now, said John Holler, low-carbon fuels and transportation senior fellow at the Center for Climate and Energy Solutions, a nonpartisan climate policy group, will pay “dividends over time” for Massachusetts.

“States like Massachusetts that are being proactive in developing SAF-specific policy incentives … see this as an economic development opportunity,” he said. “Now is the time to figure out how to develop those local supply chains and infrastructure needs.”

The contentious nature of SAF and how big of a role it should play in the decarbonization of air travel isn’t merely theoretical in Massachusetts.

Developers of a proposal to expand private jet space at Massport’s Hanscom Field airport said in filings to state regulators that they intend to “expedite the procurement” of SAF because it is a “near-term solution in reducing global GHG emissions.”

Davey said the tax break can be a meaningful tool to help the transition to SAF given that Boston collected roughly $42 million in taxes related to aviation fuel purchases at Logan Airport last year.

“A lot of technologies over the years that transition to cleaner fuel require a premium,” he said. “This allows the airline to purchase without needing to pay that premium, and frankly, then not needing to pass it on to your airline customers. And at the end of the day, people are going to travel.”

Activists opposing the Hanscom expansion, however, argue that more private jets, the most polluting mode of transportation, will wipe out Massachusetts’s work reducing its greenhouse gas emissions and view the idea that SAF will offset such travel as alarming.

A coalition of environmental groups, including Acadia Center, Green Energy Consumers Alliance, Mass Audubon, and the Environmental League of Massachusetts, wrote a letter to Healey, Tepper, and Hoffer last year urging them to “prioritize the much more cost-effective emissions reduction investments for Massachusetts” instead of promoting SAF.

“I’m disappointed. But ultimately, $30 million is a rounding error on a rounding error,” said Mark Sandeen, who led that letter from environmental groups and serves as president of MassSolar and chair of the Hanscom Area Towns Committee. “A pilot program gives legislators good political cover. They don’t have to fight over it today. And they can say, ‘Let’s see what happens.’”