There are two kinds of carbon capture, which leads to misunderstandings. One kind captures the carbon dioxide going up the smokestacks of coal-powered electrical generating stations before it can get into the atmosphere. The second kind removes some of the carbon dioxide that is already in the air. Advances in both technologies promise a dramatic decrease in the cost of each.
Update: Before continuing a summary of this news, it is worth considering fundamental objections to CCS as a legitimate, cost-effective approach to reducing emissions. For context on that, see “Carbon Capture & Storage Is Too Expensive For Reducing Power Sector Emissions” and “Carbon Capture Is Expensive Because Physics.”
Capturing Carbon In The Emissions Stream
Purist turn up their noses at the first kind of carbon capture. For them, the world would be a better place if all the coal generating facilities were shut down and replaced by renewables. That would be the ideal situation but as the saying goes, we shouldn’t let perfect be the enemy of good.
Realistically, coal-fired generating facilities will be part of the world’s energy mix for decades to come. Keeping a significant proportion of carbon emissions from ever getting into the atmosphere in the first place has to be a good thing. In fact, that is pretty much what the Obama Clean Power Plan was all about. Utility companies sued to prevent that initiative from being implemented, claiming it was too costly. But subsequent events have overtaken those objections.
A new study by the Carbon Capture and Storage Center says the latest technology — which has been trialed at SaskPower’s Boundary Dam Power Station unit 3 — is 67% less expensive that it was just a few years ago. If applied to the Shand coal-fired generating station in Saskatchewan, it would remove 97% of carbon dioxide emissions at one third the cost of similar technology in 2014.
In an email to CleanTechinca, Cory R. Channon, an executive for the International Brotherhood of Boilermakers, says, “We’re very encouraged by the economic and technical findings of the study. The CCS Knowledge Centre has long championed ground-breaking technology and proven that carbon capture can be an essential component in addressing global warming.”
The IBB and the CCS Knowledge Center have produced a 15-minute video that explains how the latest carbon capture technology works.
Removing Carbon Dioxide From the Air Just Got Cheaper
The other side of the carbon capture coin is removing carbon dioxide after it has already found its way into the atmosphere. One approach is artificial photosynthesis — using carbon dioxide to produce energy. Until now, catalysts made from expensive noble metals such as ruthenium and rhenium were required for artificial photosynthesis to take place.
Researchers from Tokyo Institute of Technology report they have found a way to make the process work using far more common and inexpensive materials such as copper, phosphorous, sulfur, and manganese.
A compound composed of copper, phosphorous, and sulfur together has proven effective as a stable redox photosensitizer. In experiments, it is capable of reducing 57% of the carbon dioxide it is exposed to with a degradation rate of only 2% over a 12-hour period. That rate of reduction is higher than that obtained by using any other photosensitizer. “To the best of our knowledge, this is the highest quantum yield for CO2 reduction using abundant elements and the yield would be comparable to that obtained with rare metals,” the researchers say.
The research also focused on catalysts composed of compounds based on manganese. Their study was published on November 27 in the Journal of the American Chemical Society.
This is the second example reported this week about replacing catalysts that use costly noble metals with far less expensive elements like iron without sacrificing performance. Carbon capture is still a novel idea. Whether it can ever offer a practical solution to the problem of an an overheating planet caused by too much carbon dioxide in the atmosphere is highly speculative.
The prospect of doing so at far lower cost than previously thought possible is ray of sunshine in an otherwise gloomy scenario in which most of the world’s nations are merely paying lip service to their promises to reduce carbon emissions while taking far too little action to make those promises a reality.