Carbon capture is one of the few technologies that seems to make both sides of the energy debate happy: the fossil fuel team is on board because carbon capture means their industry can continue sizzling CO2 without being blamed for global warming, and renewable energy advocates see it as a necessary step towards a green-energy economy. And there’s reason to be hopeful: carbon capture systems could, in theory, significantly reduce emission from energy production. But in practice there are very few large-scale carbon capture systems up and running. The reasons being that these systems are very expensive, technologically tricky, and, most importantly, there’s little incentive for companies to spend the money to build them.
But new research coming out of the the U.S. Department of Energy’s Idaho National Laboratory (INL), could help change that. In a paper published in Green Chemistry, researchers from INL explained a method for capturing CO2 and transforming it into syngas, which is a mixture of hydrogen and carbon monoxide that can be used to make fuels and be used in chemical production.
“The problem with CCS [carbon capture and sequestration] has been its economic feasibility,” said Luis Diaz Aldana, principal investigator on the experiment, in a statement. “If you can get some extra value out of the CO2 you are capturing, it’s a different story.”
Could This Mean Clean Coal?
The first thing that jumps into my head when I read about CCS technologies is: “whoa, maybe clean coal really could be possible.” That leads me down a rabbit hole, where I watch a bunch of Trump speeches where he promises clean coal, but at the same time shows that he understands absolutely zero about the technology.
Then, the more I dig and despite Trump’s grandiose promises, it becomes apparent that clean coal probably isn’t going to happen. At least not anytime soon.
The idea behind CCS (and clean coal) is actually fairly simple: pull CO2 out of smokestacks before it can escape into the atmosphere, and transport it via pipelines (either in gas or liquid form) to a secure location. Most of the CO2 is then stored deep underground, stuffed in places where the sun doesn’t shine, and hopefully kept there for a very long time.
There have been several attempts over the past decade to build clean coal power plants by using CCS technology, but so far none have been very successful. As MIT technology writer Jamie Condliffe explains, the largest clean coal experiment in the U.S. “has failed to deliver on its promise” of clean coal. Condliffe is referring to the Kemper power plant, a massive coal-fired power station in Mississippi that set out to reduce their emissions 65 percent in 2010. But now, seven years and $7.5 billion later, the plant’s “carbon capture technique has been declared too costly and problematic, and the facility will instead burn natural gas to create electricity.”
And it’s not just the cost that keeps CCS from being implemented to create clean coal. A different MIT article explains that the scale of the infrastructure needed to adequately capture enough CO2 to make fossil fuels clean is massive: “If we were to bury just one-fifth of the global carbon dioxide emissions, we would need to build an industry capable of handling twice the volume of stuff as the entire oil industry, an industry that took 100 years to develop, driven by a large and mostly expanding market.”
Ok. So does this newly discovered CCS method change any of this?
The short answer is no. Although the method developed by INL has many benefits (explained below), it isn’t a magic solution for trapping the massive amount of CO2 that is produced from burning coal and other dirty fuels. And yet, the new model developed by the INL could provide incentives for companies to capture CO2, which might help bring down emissions.
The Benefits of Turning CO2 Into Syngas
“In a normal way of doing carbon capture, there really is not a use for the CO2 and essentially you are trying to put it somewhere and keep it for a very long time,” explained Tedd Lister, research scientist at INL and group lead on the CCS project. “But the idea of what we’re doing here, is not trying to stuff the CO2 someplace, we’re actually looking to take that CO2 and convert it to either fuels or a product.”
One sector that the INL team believes could benefit from their CCS model is biofuels production. During ethanol production only about 50% of the carbon that’s being processed can be converted to ethanol, explained Aldana, “and the rest, the other 50%, is lost, mostly as CO2...so if you incorporate a technology like this, in biofuel processing you can increase the carbon efficiency and create more fuels from the CO2 that you are not using.” The ability to transform waste CO2 into something useful, namely syngas, could incentive biofuel plants to incorporate carbon capture into their processes.
It should be noted that if the CO2 that is captured through this method is turned into syngas and used as fuel, it would eventually be burned and result in CO2 being released in the atmosphere. While this might seem to completely defeat the reason for capturing the CO2 in the first place, this action still results in less emissions than if the CO2 had been allowed to escape during the initial use. It’s sort of like giving the CO2 a second chance of becoming energy, rather than going straight into the atmosphere.
The INL method of CCS could also be used to transform the captured CO2 into chemical substances, like plastic, which would result in a carbon sink. “You would actually have a net reduction in CO2 because you could think of the plastic as something that will last for a very long time,” explained Lister. “The carbon will be trapped in the material and not the atmosphere.”
The INL team has shown that their method of CCS works, on the small-scale; it’s more energy efficient than traditional CCS, and it yields useful materials. And while there’s a fair amount of tinkering and tweaking required before the model is ready to scaled and used by industry, the team believes change is coming. “Whether it’s our technology or someone else’s technology, these changes will evolve over time,” said Lister. “And you think things move pretty slowly, but if you look at now from 20 years ago, there’s been quite a change that’s been made.”
So, in summary: is it a solution to clean coal? Probably not. A step to reducing emissions? Probably.