With efforts to reduce the burning of fossil fuels floundering the recent announcement of a technology breakthrough for proposed devices that would pull carbon dioxide out the atmosphere provides some hope that catastrophic climate change can be avoided. The breakthrough involves a way to drastically reduce the amount of energy needed to remove the gas from the material, or sorbent, used to soak up carbon dioxide from the atmosphere. According to an article in the Guardian the US patent application shows that the reduction in energy needed to remove carbon dioxide from the sorbent involves changes in humidity.
Before anyone thinks the global warming problem is solved and stops trying to prevent the building of coal-fired power plants it should be noted that some serious problems would remain even if a prototype device, which should be functioning within 2 years, meets all expectations. One of the problems is what to do with the captured carbon dioxide. The storage problem remains to be solved. The article says that the research team, led by Columbia University physicist Klaus Lackner, is working on a solution. Another problem might be cost. Although each device is expected to initially cost only a couple hundred thousand dollars there will be a need for millions of the devices to be operating. A total cost of over a trillion dollars seems possible.
This proposal may turn out to be a dead end in the effort to limit global warming but then again perhaps not. At this point it seems a better bet than the world leaders agreeing on how greenhouse gas emissions can be meaningfully reduced. That effort appears to be going nowhere.