A major new facility to pull carbon dioxide out of the atmosphere started operating in Iceland on Wednesday, a boost to an emerging technology that experts say could eventually play an important role in reducing the greenhouse gases that are warming the planet.

The carbon capturing plant, perched on a barren lava plateau in southwest Iceland, is the biggest of its kind, its builder says, increasing global capacity for the technology by more than 40 percent. Many climate experts say that efforts to suck carbon dioxide out of the air will be key to making the world carbon neutral in the coming decades.

By 2050, humanity will need to pull nearly a billion metric tons of carbon dioxide from the atmosphere every year through direct air capture technology to achieve carbon neutral goals, according to International Energy Agency recommendations from earlier this year. The plant in Iceland will be able to capture 4,000 metric tons annually — just a tiny fraction of what will be necessary, but one that Climeworks, the company that built it, says can grow rapidly as efficiency improves and costs decrease.

“This is a market that does not yet exist, but a market that urgently needs to be built,” said Christoph Gebald, a corkscrew-haired Swiss engineer who co-founded and co-directs Climeworks. “This plant that we have here is really the blueprint to further scale up and really industrialize.”

For now, the Icelandic installation, which is called Orca — phonetically the same as the Icelandic word for “energy” — is an unlikely global savior. Human-sized fans are built into a series of boxes that are the size of standard 40-foot shipping containers. They sip carbon dioxide out of the air, catching it in spongelike filters. The filters are blasted with heat, about the same temperature needed to boil water, freeing the gas. Then it is mixed with water and pumped deep into underground basalt caverns, where over time it cools down and turns into dark-gray stone.

It is a straightforward chemical reaction: taking the carbon dioxide that is causing global warming out of the air and tucking it away where it can do little harm.

Pumping CO2 into the ground is just one way to dispose of it. It can also go to other uses, as well. Energy companies can mix the carbon dioxide with hydrogen to make fuel. Farmers can feed their plants with it. Soda manufacturers can use it to fizz their drinks — something a Swiss customer of Climeworks did a few years ago when there was a carbonation shortage.

At the moment, the costs are high: about $600 to $800 per metric ton of carbon dioxide, Gebald said, far from the levels around $100 to $150 per ton that are necessary to turn a profit without the help of any government subsidies. The costs reflect both the hand-hewn nature of the technology — Climeworks’ installations are mostly built by hand for now, not through automation — and also the large amounts of energy needed to power the CO2 capture process.

The Orca installation was built in Iceland both because the tiny island nation has ample supplies of climate-friendly geothermal energy as well as just the right underground geology to make it easy to capture carbon.

“If people hear those numbers for the first time they might think, ‘Oh wow, that’s expensive,’ but it’s always a question of what you compare it to,” Gebald said. The state of California subsidizes electric cars around $450 to $500 per ton of carbon emissions saved over the course of a vehicle’s expected life, for example, he said.

Longer term, Gebald thinks prices can get cheaper — by 2030, he said they expect prices around $200 to $300 per ton. By the late 2030s, he thinks it will be half that — about the price where it will be a competitive method of reducing global emissions.

“That’s really the main problem, whether you can make it cheap enough. And there’s reason to believe that it could be possible,” said Stephen Pacala, the director of the Carbon Mitigation Initiative at Princeton University. If the technology were to cost $100 per metric ton of carbon dioxide and the aviation industry paid to offset the emissions from its aviation fuel, it would increase the cost of fuel by about $1 a gallon, well within the range of seasonal price fluctuations, Pacala said.

The new technology “could be a big deal. It could be a really big business,” he said.

World leaders see a promising new possibility, too.

“This is indeed an important step in the race to net-zero greenhouse gas emissions, which is necessary to manage the climate crisis,” Icelandic Prime Minister Katrin Jakobsdottir said Wednesday at the ceremony marking the opening of the Orca plant. “This almost sounds like a science fiction story, but we do have other examples in our history of amazing advances in technology.”