GLASGOW — The U.S. Department of Energy on Friday will unveil its biggest effort yet to drastically reduce the cost of technologies that suck carbon dioxide out of the atmosphere, in a recognition that current strategies to lower greenhouse gases may not be enough to avert the worst effects of climate change.
Speaking at the United Nations climate summit, Jennifer Granholm, the energy secretary, planned to announce that her agency will invest in research in the nascent field of carbon removal, with a goal of pushing the cost under $100 per ton by 2030. That’s far below the price tag for many current technologies, which are still in early stages of development and can currently cost as much as $2,000 per ton.
The ultimate aim is to identify techniques that can remove billions of tons of carbon dioxide already in the atmosphere and permanently store it in places where it will not warm the planet.
“By slashing the costs and accelerating the deployment of carbon dioxide removal, a crucial clean energy technology, we can take massive amounts of carbon pollution directly from the air and combat the climate crisis,” Ms. Granholm said in a statement.
The idea of pulling carbon dioxide out of the atmosphere, once considered the stuff of science fiction, has attracted increasing interest in recent years. Hundreds of countries and companies have now pledged to reach “net zero” emissions by midcentury, essentially a promise to stop adding greenhouse gases to the air, to limit global warming to 1.5 degrees Celsius above preindustrial levels. That’s the threshold beyond which many scientists say the planet will experience catastrophic effects from heat waves, droughts, wildfires and flooding The planet has already warmed by about 1.1 degrees Celsius.
But reaching net zero may require two strategies. First, countries will have to deeply cut their emissions from burning oil, gas and coal in power plants, factories and cars, and to switch to cleaner sources of energy. But they may also need to remove carbon dioxide from the atmosphere to offset emissions from sources that are difficult to clean up, such as agriculture.
The U.N.’s Intergovernmental Panel on Climate Change estimates that the world may ultimately have to remove 100 billion to one trillion tons this century to stay below 1.5 degrees, in part because countries have been so slow to reduce their emissions.
Yet, current techniques are no match for the challenge. One popular option is to plant trees, which naturally absorb carbon from the air. But trees take years to mature, there’s only so much land available and forests can burn in wildfires, releasing carbon back into the atmosphere.
More recently, a number of companies have been tinkering with technological solutions such as direct air capture, which involves using giant fans to pull carbon dioxide out of the air and bury it underground. (This is different from carbon capture and storage, another nascent technique that traps carbon dioxide at the smokestacks of power plants and factories before it enters the atmosphere.)
Climeworks, a Swiss start-up, recently opened the largest such direct air capture plant to date in Iceland. But that early plant has the capacity to remove only 4,000 tons of carbon dioxide per year — equivalent to the emissions from 870 cars — and Climeworks’ current costs are around $600 to $800 per ton, though it hopes to drive down that price over time as it builds more plants and refines the technology.
Other ideas are even more expensive. Stripe, a payment services company, has voluntarily paid $9 million over the past two years to a variety of carbon removal start-ups, including a company that grows carbon-absorbing kelp and buries it deep in the ocean. But many of those techniques cost between $200 and $2,000 per ton of carbon dioxide, and it is uncertain how well they work.
As part of its new effort, the Energy Department plans to direct scientists at its national labs to research different approaches and to fund demonstration projects so that engineers can figure out how to reduce costs. The agency will also develop standards to assess whether carbon removal techniques are working as advertised.
The program is modeled after the Obama-era Sunshot Initiative, which is credited with helping to usher solar power into the mainstream during the 2010s. The agency directed research efforts toward lowering costs and worked with private companies to ease barriers to deployment.
The announcement is part of the Biden administration’s Energy Earthshots Initiative, which aims to accelerate the deployment of nascent technologies to fight climate change. Earlier this year, the department announced similar efforts to reduce the costs of both clean hydrogen fuels and advanced batteries that can backstop wind and solar power.
In an interview, Jennifer Wilcox, the principal deputy assistant secretary for the agency’s Office of Fossil Energy and Carbon Management, said that investments in carbon removal should not be seen as an excuse for countries and businesses to ease up on efforts to reduce their fossil-fuel emissions, not least because there was still no guarantee that carbon removal would be viable on a massive scale.
“Carbon removal won’t ever replace the need for quickly cutting our emissions,” Dr. Wilcox said. “But scientists are telling us that we are likely going to need to remove billions of tons of carbon dioxide from the atmosphere by 2050 if we want to avoid the worst impacts of climate change. And if we don’t start investing in solutions today, we’re not going to get there by midcentury.”
The agency, Dr. Wilcox added, does not plan to favor any specific technologies early on. Instead, officials will study a vast range of approaches to see which ones appear most promising. That could include direct air capture, but it could also include, for instance, testing how certain minerals might absorb carbon dioxide when they were crushed up and sprinkled over vast surfaces, through a process known as enhanced weathering.
Dr. Wilcox also noted that some natural techniques for carbon removal, such as planting trees or farming methods that sequester carbon dioxide in the soil, were often advertised at prices far cheaper than $100 per ton today. But researchers still need to figure out how reliable these techniques are, and whether the carbon can be stored for long periods of time.
“Part of this effort is being able to show the true price tag of these approaches once you add in the costs of verification and long-term monitoring,” she said.
The Energy Department could soon have enormous sums of money for the effort. President Biden has proposed hundreds of millions of dollars in his budget for various carbon removal and storage techniques. And the bipartisan infrastructure bill currently pending in Congress provides $3.5 billion to create four direct air capture “hubs” across the country, where new technologies can be demonstrated.
“It’s surprising how quickly this has become mainstream,” said Erin Burns, executive director of Carbon180, a nonprofit organization focused on carbon removal. “Just a few years ago, hardly anyone was talking about carbon removal. Now it has broad bipartisan support.”
Ms. Burns said that the Energy Department’s cost target of less than $100 per ton by 2030 was an ambitious but plausible goal. At that price, carbon removal could become a viable industry, supported by both government incentives and the increasing number of companies that are seeking to erase their emissions as part of their net zero pledges.
Carbon removal does have its critics. Some climate activists have worried that companies may rely on the uncertain promise of such technologies in the future to avoid the hard work of cutting emissions today. They also point to the fact that a number of oil companies have championed the idea as a way of offsetting emissions from pumping out more crude.
Yet other environmentalists say that the world will need to explore as many options as possible to limit the increasing damage from climate change.
“This shouldn’t distract us from the work of cutting emissions, I agree,” said Jake Higdon, manager for U.S. climate policy at the Environmental Defense Fund. “But if there are ways to do carbon removal that are safe, responsible and affordable, then we need to figure that out as quickly as possible.”
