A new plan for carbon sequestration
Carbon sequestering is a method being looked at to help mitigate rising levels of carbon dioxide in our atmosphere. Research has been done on sequestering the gas in geological formations underground, however this has proven to be impractical for most applications. There are concerns that the gas will escape, issues surrounding the proximity of the emissions sources to the disposal sites, as well as the amount of viable storage space. Now researchers at Harvard University and Columbia University have developed a new plan for carbon sequestration: storing it under the sea.
This new plan is being touted as a secure, practical and near-limitless way of storing excess carbon dioxide for sources that are far from suitable land-based geographical locations. The technique involves liquifying the carbon dioxide and pumping it into the porous sediment several hundred meters below the sea, 3 kilometers deep. The high pressure and cold temperatures would mean the carbon dioxide was denser than the surrounding water, effectively trapping it there. The carbon dioxide would react with the deep cold water and would form hydrate ice crystals, further sealing the carbon. The researchers hope to run a large scale test of this idea within the next 5 years. This technology is promising, in part due to the storage capacity available:
Sea-floor injections also offer an immense amount of storage capacity. If all the known geologic reservoirs for conventional storage were useable, they could store all the carbon dioxide currently produced each year, and continue doing so for 80 years at current emission rates. In contrast, sea-floor storage around the United States alone could store thousands of years worth of U.S. carbon dioxide production, the researchers estimate.
Concerns over cost and safety still exist however, and this method is only practical for areas close to deep waters. And of course, having such an option available will promote continued use of petroleum-based fuels. The best solution by far is to phase out fossil fuels, in favor of environmentally-friendly renewable systems. Sure, carbon sequestering may work for a few point source applications such as industrial stacks, but what about vehicle emissions?
Undersea carbon sequestration may have a place in our future, but it’s by no means a final solution. Ultimately, the only practical solution isn’t to find a place to store our excess carbon, we need to stop producing it altogether.