Delta aims to become first "carbon neutral" airline

Delta Airlines is spending $1 billion over the next decade to essentially cancel out all of its future greenhouse gas emissions beginning March 1, the company announced Friday.

The big picture: Delta is the world’s biggest airline by revenue, and this news is the latest in a rapidly growing trend of corporations announcing climate-change goals in response to public and investor pressure.

Driving the news: Delta is able to immediately become carbon-neutral by purchasing what are called carbon offsets, financial transactions that ostensibly help cancel out carbon emissions by preventing emissions elsewhere in the world, like planting trees or supporting renewable energy.

• The company isn’t disclosing how many offsets it’s purchasing — or how much it’s spending on that. But it’s likely to be a huge number given the scale of its announcement.
• When Delta announced in 2012 it was capping its emissions at the levels current to that year, it purchased more than 16 million offsets.
• Delta is the 8th most energy-efficient airline out of a study of 11, mainly due to its older fleet of airplanes that are less efficient than new models, but it's in the process of replacing them. That's according to a recent report by the nonprofit International Council on Clean Transportation.

Yes, but: Delta says it’s going to minimize its reliance on carbon offsets, though it also concedes technologies enabling it to directly reduce its emissions aren’t readily available or in some cases even invented yet. It plans to research those technologies and others with its new allocation of $1 billion.

"We are on a journey, and though we don’t have all the answers today, we know that our scale, along with investments of time, talent and resources will bring meaningful impact to the planet and ensure the sustainability of our business for decades to come."

Where it stands: Virtually all airlines rely on carbon offsets to cut their emissions. That’s because no commercially available technology exists to affordably make large quantities of low-carbon or zero-carbon jet fuel, whether battery-powered or another kind of liquid like biofuels.

• JetBlue announced earlier this year it was going to become carbon neutral by July.
• Other airlines with commitments include Air France (cutting emissions per passenger by 50% in 10 years) and Australian carrier Qantas (net-zero emissions by 2050), per Travel Market Report.

But, but, but: Carbon offsets are, at best, "very opaque and definitely hard for the average person to understand," said Sola Zheng, an expert on aviation at the nonprofit International Council on Clean Transportation.

• The quality of offsets also faces scrutiny. Doubt persists about whether offsets purchased actually reduce emissions and don’t just throw money at projects, such as planting trees or building a wind farm, that would have happened regardless.
• A United Nations organization is working on developing standards to ensure quality offsets in an industry-wide program, but no uniform quality-control measures exist for carbon offsets airlines and others purchase, besides disparate third-party programs.

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