Carbon Capture Can Compliment the Circular Economy with E-fuels

The carbon capture field has come under fire, with critics charging that it simply enables fossil energy stakeholders to continue extracting coal, oil and natural gas from underground. But not all carbon capture systems are alike. When airborne carbon dioxide is used to replace fossil-sourced fuels or chemicals with synthetic ones, carbon capture systems can contribute to the circular economy and help stimulate more renewable energy development, too.

Wind, solar and the renewables-to-liquids movement

The connection between renewable energy and synthetic fuels is already emerging in the field of e-fuels. Also called solar fuels or electrofuels, these new synthetic liquid fuels use electricity to run electrolysis systems, which separate water into hydrogen and oxygen. That is a significant sustainability improvement over the conventional hydrogen supply chain, which depends on extracting hydrogen from natural gas, or coal to a lesser extent.

With this green hydrogen in hand, carbon is another ingredient needed to make new liquid fuels and chemicals, and that can come from carbon capture systems.

Still, e-fuels do not fit the circular economy model if the electrolysis equipment runs on electricity from a coal or gas power plant. Low-cost wind or solar power makes all the difference.

Solving the renewables-to-grid puzzle

One of the key obstacles faced by wind and solar developers is a simple matter of transmission availability. Optimal locations for renewable energy development are abound in the U.S., but many are in remote locations. Building new transmission lines and connecting them to the nation’s grid can be a difficult, if not impossible, endeavor.

The e-fuels field can provide a solution by converting and transporting renewable energy in liquid form, rather than depending on a grid connection. Liquids, e-fuels and chemicals can be transported using existing infrastructure, including pipelines, roads, railways and shipping ports. E-fuels can also leverage existing tank farms and other facilities for storage. In contrast, storing electricity from wind or solar farms involves building new battery arrays and other energy storage systems.

To be clear, risks and hazards are always present when transporting or storing fuels and chemicals, sustainably sourced or not. But with the risks and hazards of climate change in full view, e-fuels present an opportunity to address a broader crisis from two sides: replacing extractive resources with more sustainable ones and capturing airborne carbon.

Who’s going to pay for all this?

Another key obstacle is cost. Though the cost of green hydrogen is dropping, the United States Department of Energy calculates that low-carbon fuels cost about $10.00 per gallon, far above the typical cost of fossil-sourced gasoline and other fuels.

To push costs down and help accelerate the renewables-to-fuels movement, the Department of Energy launched $41 million in funding for new reactor-based systems that process renewable energy, water and captured carbon into new fuels and chemicals.

“Renewable energy resources are often not co-located with the current U.S. power grid, and by enabling the transportation of sustainable fuels the selected projects can reduce interconnection barriers while helping cut emissions from hard to decarbonize industrial sectors,” according to the department’s Advanced Research Projects Agency-Energy office (ARPA-E), which is charged with administering the fund.

ARPA-E’s mission is to fund new, transformative energy systems that have not attracted sufficient support from private investors. This funding marks the first time it is supporting efforts to make liquid fuels. 

A new decarbonization pathway

ARPA-E makes it clear that the new funding program is aiming for synthetic fuels that can be used as a drop-in replacement for conventional fuels. That will make a significant contribution to decarbonization over the coming years. Though electric vehicle sales are picking up, millions of gas- and diesel-fueled vehicles will remain road-worthy long into the future, and they will continue to use liquid fuels of one kind or another.

Sustainable aviation fuels are also a target of the program. The North Carolina startup Susteon previously received awards from the Department of Energy and the North Carolina Department of Commerce. Now, its receiving an additional almost $5 million from ARPA-E for five innovations in the production of sustainable aviation fuels, including an energy management system that optimizes the availability of wind or solar energy.

The new program is yet another indication that simply capturing airborne carbon and injecting it underground is an outdated approach that fails to proactively replace fossil energy with renewable resources. New systems and technologies are presenting a more sustainable, alternative pathway.