The conclusion of the Paris Agreement in 2015, in which almost every nation committed to reduce their carbon emissions, was supposed to be a turning point in the fight against climate change. But many countries have already fallen behind their goals, and the U.S. has now announced it will withdraw from the agreement. Meanwhile emissions worldwide continue to rise.

The only way to make up ground is to aggressively pursue an approach that takes advantage of every possible strategy to reduce emissions. The usual suspects, such as wind and solar energy and hydropower, are part of this effort, but it must also include investing heavily in carbon capture, utilization and storage (CCUS)—a cohort of technologies that pull carbon dioxide from smokestacks, or even from the air, and convert it into useful materials or store it underground.

Although CCUS has been opposed as too expensive and unproved, recent gains have made it far more effective. Improvements such as chemical compounds that are more efficient at latching onto carbon could drive the cost down from $100 per ton of captured carbon in 2016 to $20 per ton by 2025, according to a 2016 article in Science. Start-ups are also developing new tactics, among them the transformation of trapped carbon into fertilizer, which could spur further savings.

Without CCUS, the level of cuts needed to keep global warming to two degrees Celsius (3.6 degrees Fahrenheit)—the upper limit allowed in the Paris Agreement—probably cannot be achieved, according to the International Energy Agency. By 2050 carbon capture and storage must provide at least 13 percent of the reductions needed to keep warming in check, the agency calculates.

Three primary CCUS paths lead us to this goal: retrofitting existing power plants to strip carbon dioxide from the exhaust produced by fossil-fuel electricity plants; reducing emissions in industries that cannot run on renewable energy; and directly removing carbon from the air. Cutting emissions from existing electric power stations with CCUS could be made more appealing in a future with a circular carbon economy, in which captured carbon could be resold and recycled for other uses—for instance, serving as a raw material for making concrete or plastics.

CCUS technologies can also help decarbonize emissions in heavy industry—including production of cement, refined metals and chemicals—which accounts for almost a quarter of U.S. emissions. In addition, direct carbon-removal technology—which captures and converts carbon dioxide from the air rather than from a smokestack—can offset emissions from industries that cannot readily implement other clean technology, such as agriculture.

The basic idea of carbon capture has faced a lot of opposition. Skepticism has come from climate deniers, who see it as a waste of money, and from passionate supporters of climate action, who fear that it would be used to justify continued reliance on fossil fuels. Both groups are ignoring the recent advances and the opportunity they present. By limiting investment in decarbonization, the world will miss a major avenue for reducing emissions both in the electricity sector and in a variety of industries. CCUS can also create jobs and profits from what was previously only a waste material by creating a larger economy around carbon.

For CCUS to succeed, the federal government must kick in funding for basic research and development and offer incentives such as tax breaks for carbon polluters who adopt the technology. The Trump administration has repeatedly tried to slash energy technology R&D, with the Department of Energy's CCUS R&D cut by as much as 76 percent in proposed budgets. But this funding must be protected.

There is hope for doing that. The FUTURE Act, the provisions of which were passed with the February 2018 budget bill and which was championed by a bipartisan coalition in the Senate, contains tax incentives that are important steps toward making CCUS economical. The same bipartisan group of senators has proposed the USE IT Act, which would amplify support for CCUS technology by directly funding research and development and by setting up a prize competition to reward deployment.

The transition to clean energy has become inevitable. But that transition's ability to achieve deep decarbonization will falter without this wide range of solutions, which must include CCUS.