Which technology will save the climate? Renewables or carbon capture?Which technology will save the climate: renewables, carbon capture or both? Photo credit: Lukas Schulze/Getty Images

By Marco Poggio

Climate scientists have for decades researched ways to extract carbon dioxide from the atmosphere as a way to slow climate change, but while their work has progressed from a handful of fringe theories to promising technologies, they remain controversial. That’s partly because they have drawn an unlikely backer: the fossil fuel industry.

Since at least the 1980s, researchers have devised and tested technologies aimed at capturing CO2 from the air—a field broadly referred to as carbon dioxide removal or negative emissions technologies.

Governments and private investors have begun to hail those technologies as a viable path toward slowing global warming and a report by the Intergovernmental Panel on Climate Change (IPCC) mentions them as necessary to meet the terms of the Paris Climate Agreement. They have drawn significant investment from oil, gas and coal companies looking for ways to continue developing fossil fuels as the world moves toward cleaner energy.

But some scientists and policy makers are alarmed that a reliance on these technologies will continue our dependence on fossil fuels and will impede the transition to renewable energy sources.

A recently published study by the Center for International Environmental Law warned that some technologies, in particular carbon capture, utilization, and storage (CCUS) technologies, could slow the transition to renewables.

“CCUS is valuable to the fossil fuel industry in three key ways: it expands oil production, provides a lifeline to a declining coal industry, and further entrenches the overall fossil fuel economy,” the report says. “Incentivizing CCUS through policy and relying on it in planning will likely slow the transition away from fossil fuel investments and undermine broader efforts to mitigate climate change.”

The debate comes with few black-and-white solutions. Touting technology and innovation has become a talking point in dealing with climate change by Republicans who feel they can no longer run from the issue altogether, but climate activists argue it is little more than their latest cover for pushing climate action indefinitely into the future. And none of the technologies are close to being developed at a scale large enough to have a true impact on global warming, a process that would have to be coordinated among many countries on a vast global scale.

At the same time, many climate scientists argue negative emissions technologies are absolutely necessary to fend off the worst impacts of global warming.

For the fossil fuel industry, which sees the cost of renewables falling rapidly, negative emissions technologies provide a scenario in which fossil fuels—in particular coal, by far the largest contributor to the world’s CO2 emissions—can survive the transition to cleaner energy.

An Array of Ideas

Negative emissions technologies differ widely in terms of techniques and results. Some involve natural ways to extract CO2 from the air, such as planting more trees, restoring wetlands or modifying the soil to make it absorb more CO2.

Others require elaborate feats of engineering. Carbon dioxide can be captured from the smokestacks of power plants, refineries, iron, steel, or cement plants; or it can be extracted directly from the air, where it’s more rarefied, by way of giant fans, with a process called direct air capture.

Some negative emissions technologies have failed to produce tangible results and others have produced little more than skyrocketing costs: one high-profile carbon capture and storage project in Kemper, Miss., was supposed to be the vanguard of clean coal technology but ended up costing $7.5 billion and the technology was scrapped altogether in favor of burning natural gas.

Other technologies, like direct air capture—which works to separate carbon dioxide from the air and then store it—are on  the rise, thanks to innovations that are making it less expensive and more appealing to investors.

Harvard engineer David Keith has estimated the direct air capture system he devised could cut the cost of CO2 extraction from $1,000 per metric ton to a range between $94 and $232 per metric ton. His company, Carbon Engineering, received investments from billionaire Bill Gates, oil magnate Murray Edwards, and more recently, oil giants Chevron and Occidental.

Captured CO2 with negative emissions technologies is either stored in deep underground geological formations in the case of carbon capture and storage, or used for production of chemical fuels, biofuels and heating system fluids.

The vast majority of captured CO2, however, is currently used to extract oil. In a process called enhanced oil recovery, compressed CO2 is injected into depleted oil reservoirs, causing oil to expand and flow more easily to surface.

The role of CO2 in oil extraction is what makes many critics think carbon capture and storage won’t help with climate change.

Steven Feit, a lawyer and one of the authors of the Center for International Environmental Law report, said the unbreakable relationship between fuel combustion and CO2 removal helps sustain a vicious circle where fuel is burned, CO2 is produced, then captured, then used to produce more fuel.

“We’re talking about a system that would be making fossil fuels harder to transition away from, while also making it easier for old companies to make more oil. There’s a kind of perverse relationship between all these moving parts,” Feit told Climate Liability News.

Feit said he believes the majority of researchers and engineers studying negative emissions technologies are well-intentioned, but their solutions will not avoid the need for drastic CO2 emissions cuts and the boosting of solar and wind energy.

“What is required to effectively deal with climate change is a transition from the kinds of systems we have to ones which are sustainable and low or zero carbon,” he said.

A Well-Funded Effort

The U.S. government has long supported negative emissions technologies projects, with the Department of Energy having funded research since at least 1997. Last month, Secretary Rick Perry awarded $24 million in funds to eight companies for research and development of CCUS technologies. The funds, which will come from the Office of Fossil Energy, will add to the $28.9 million in research fund awarded during fiscal year 2018.

“By 2040 the world will still rely on fossil fuels for 77 percent of its energy use. Our goal is to produce them in a cleaner way,” Perry said in a statement.

The federal government also provides tax credits to fossil fuel companies that incorporate CO2 capture and storage systems in their operations.

All major oil companies have invested in negative emissions technologies. Currently, there are 23 large-scale CCUS projects around the world that are either operating or under construction.

In its “2019 Energy and Carbon Summary,” ExxonMobil reported investments of more than $9 billion in the development of lower-emission energy solutions that include carbon capture and storage. The company boasts having 30-year expertise in storing captured CO2 underground “in a safe and secure fashion.”

In its “Sky Scenario,” Shell projected the deployment of 10,000 large-scale carbon capture and storage (CCS) facilities by 2070, in a world with net-zero CO2 emissions.

Chevron has invested more than $75 million in CCS research and development over the past decade. The company is also part of the CO2 Capture Project, an industry group of four major companies, which include BP, that have joined resources into CCS research.

Those investments, while they may sound large, are tiny compared to the overall research and development budgets of the oil companies. Exxon, for one, plans to invest $200 billion in the next seven years on traditional oil and gas projects around the world.

It’s All About Scale

While engineers, scientists, governments and industry all look for the magic bullet of some kind of carbon capture and storage, the reality is none of today’s existing technologies are feasible on any kind of realistic scale. And even if they were, not all climate engineers are convinced that transforming captured CO2 into products would be viable on a large enough scale to make a difference.

Massachusett Institute of Technology engineer Howard Herzog believes the best way to deal with carbon dioxide is to store it underground. He also thinks direct air capture technology is not cost effective, is too complicated and has the potential of removing only 1 or 2 percent of global emissions.

“I’ve been very critical of direct air capture in my writings. I think the people who are promoting it are under-realistic. I just think it’s too expensive. Let me just say: I don’t believe the cost numbers that they’ve put out,” he said.

Herzog, who discloses that he receives funding from Exxon to research CCS technologies, said they won’t solve the issue of climate change.

“Carbon dioxide removal and negative emissions can be an important part of climate change policy. It doesn’t replace current efforts or lack of current efforts,” he said. “The best way to take CO2 out of the atmosphere is not put it there in the first place.”

A spokesperson from Climeworks, a Europe-based direct air capture company, said in an email that even with tight climate regulations in place, negative emissions technology are still needed to offset the CO2 currently in the atmosphere.

“We have already passed the point of an either/or-decision. To reach the Paris agreements, all means of promoting renewable energies and emission reductions have to be deployed together,” the email said.

The Center for International Environmental Law report points out Climerwork’s partnership with car maker Audi in creating fuels made with captured CO2 that can be used alongside regular fuel as an example of a lingering influence fossil fuels still have on markets, and a sign of the industry opposition to change.

The report also highlights the role of government funding and private investments in negative emissions technologies in helping the fossil fuel industry build new infrastructure.

A new network of of pipelines will have to be built in order to transport the CO2 from the capture facilities to appropriate geological formations underground where it will be stored for hundreds of years. Those storages will have to be monitored to ensure the carbon dioxide doesn’t find its way up to the surface. The massive amount of work that will be required to maintain a system highly reliant on negative emissions technologies will be dangerous step backwards, the report says.

“We need to transition away from reliance on fossil fuels. Anything that moves us toward greater reliance will not be a solution,” the report says.

Herzog disagreed with the main claim in the Center for International Environmental Law report—that negative emissions are helping the fossil fuel industry.

“Fossil fuel is 85 percent of our energy economy. There’s good and bad. With climate change, the point is to keep CO2 out of the atmosphere. So if you can use fossil fuels without putting CO2 into the atmosphere, what’s wrong?” he said.  

Herzog said the public has preconceived ideas about climate change.

“On the right, they deny climate change, because they don’t want to deal with it. On the left, they want to use climate change as reason we just do renewables. ‘We don’t need nuclear, we don’t need CCS, we’ve just got renewables’ That’s not right, either. Renewables can’t do it all. It’s going to be very hard to get to net zero emissions, and you really need every technology you can to help you.”

Sven Teske, a German engineering and researcher at the University of Technology, Sydney, said renewables have the potentials to replace fossil fuels sooner than most people think. For over 20 years, Teske researched the market potential of solar and wind technologies, and came up with scenarios where renewables are able to sustain the world’s power demand.

“Those will be by far the dominating technologies in the next decade or two,” he said. “CCS is much more expensive than renewables, because renewables are already cheaper than coal, and if you had new equipment then it’s even more expensive. And also, you have all the structural cost to get the CO2 underground and keep it there.”

Teske said he understand the fossil fuel industry is feeling cornered by the advancing of ever cheaper renewable power technology. However, he said, fossil fuel companies have the capital to experiment a pivot to renewables. As an example, he mentioned Shell, which invested in offshore wind power, including a recently built wind turbine project off the coast of Norway.

Teske believes the negative emissions technology has been surpassed and the right direction is now in renewables.

“This industry is moving in this direction,” he said. “CCS has been discussed over the last 20 years. At the end of the day, close to nothing has been delivered, while renewables now are the main part of newly built power plants. It is actually already happening.”

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