The first three Democratic presidential candidates to declare their plans to tackle the climate crisis are focussing on setting deadlines to neutralize US pollution. But one Democrat is proposing something vastly different. Environmental advocates are likely to find it unacceptable, but some experts say it might be necessary.

Maryland congressman and long shot 2020 candidate John Delaney wants to scale up technology to capture the carbon dioxide pollution heating the planet, and transport it in pipelines crisscrossing the country.

John Delaney’s carbon throughway plan. Photograph: Courtesy of the John Delaney campaign

Polluting facilities from America’s industrial regions in the midwest and Gulf South would send their carbon to Texas to be used in oil drilling operations. The federal government would use the money currently going toward fossil fuel subsidies to help fund the effort. He also backs a tax on carbon pollution that he says could cut emissions 91% by mid-century.

Environmentalists are likely to oppose the plan because it would allow the continued use of fossil fuels and because it would require a vast network of new pipelines.

But Delaney said international science shows humans will have to pull carbon from the atmosphere – in addition to rapidly slowing emissions – to avoid the worst of climate change.

“I am as in favor of getting us off fossil fuels as fast as [those critics] are,” he told the Guardian on the phone from the campaign trail in flood-damaged Iowa. “But I also want to solve the climate problem by getting us to net-zero by 2050. And I don’t believe we can get to net zero by 2050 without engaging direct air carbon capture.”

He added that the pipelines would be constructed where right-of-way permits have already been approved for existing oil and gas pipelines.

Delaney has proposed achieving the vast majority of US pollution reductions with a tax on carbon. The money collected would be returned to Americans who might have to pay more for gasoline, electricity and other goods. That would cut pollution from electricity and transportation. But industries like cement-making would be harder to clean up. Delaney says that’s when carbon capture will be needed.

Tiernan Sittenfeld, senior vice-president of government affairs for the League of Conservation Voters, said the group welcomes creative and ambitious solutions and appreciates Delaney’s “longtime leadership on climate change”.

But “while there are elements of his overall climate plan that we support, the proposed carbon throughway would enable continued oil extraction at a time when we need more than ever to transition away from fossil fuels”, she said. “The climate crisis requires that we transform our economy at a pace and scale never seen before in human history, and a network of carbon pipelines that would incentivize more fossil fuel extraction takes us in the wrong direction.”

The United Nations’ Intergovernmental Panel on Climate Change (IPCC) has emphasized that the world will need to find ways to absorb carbon pollution, as well as limit it. That could be from increased tree cover and vegetation or with technology to pull it from the atmosphere. Delaney cited a National Academies of Sciences report that found that for climate and economic reasons, direct-air carbon capture will “need to play a significant role in mitigating climate change”.

Carbon capture technologies are currently available, but not at the large scale and low cost that would be needed for Delaney’s plan. Demand for captured carbon is low, making it impossible for companies to justify the expense. Delaney would spur demand by having the government pay for captured carbon at auction with money currently used to subsidize the fossil fuels industry.

Delaney’s carbon tax would start at $15 a ton of carbon and increase $10 a year. He cosponsored a bill laying out the details with some of the few congressional Republicans seeking climate action.

The congressman said he would ask Congress to pass a carbon tax in his first year as president.

“It can be passed with every Democrat in Congress and all Republicans who live in coastal states,” he said. “That is the coalition that I think will do the first big thing we need to do on climate in this country.”

A handful of presidential contenders have said they would consider a carbon tax if elected, according to responses to the the New York Times. But none of them have made it a central element of their platform yet.

Other Democrats who have rolled out climate plans – Washington governor Jay Inslee, former Texas congressman Beto O’Rourke and Colorado senator Michael Bennet – have proposed dates by which to reach net-zero carbon pollution. Inslee aims for 2045 and O’Rourke and Bennet for 2050.

Former vice-president Joe Biden’s campaign has pushed back on reports that he might take a moderate approach to climate change that includes natural gas. Many have endorsed a Green New Deal to curb climate change while protecting vulnerable Americans. Some – including Senator Bernie Sanders – have sponsored ambitious climate legislation in the past.

Delaney also splits with some environmentalists on another thorny issue – nuclear power.

“Let’s put it this way, I’m not anti-nuclear because I don’t think you can be anti-nuclear and pro dealing with climate change,” Delaney said.

Nuclear power in the US accounts for about half of the zero-carbon electricity. Delaney wants to invest in smaller, more stable power plants, he said.