In view of the Paris agreement (UNFCCC, 2015), interest for technologies that can guarantee stable greenhouse gases emission reduction and negative ones in the case of capture of biogenic carbon dioxide has continued to grow. Many researchers have highlighted that to meet the requirements of the climate international policy signed in Paris, carbon dioxide along with other greenhouse gases emissions should be reduced at high rates in years to come and carbon dioxide should be actively removed from the atmosphere in huge amounts.
A number of methods are available for carbon dioxide removal including, forest management, afforestation, a combination of bioenergy with carbon capture and storage, dedicated activities such as direct air capture and sequestration and enhanced weathering of olivine rocks. There are many research works on the potential obstacles to an increase of these negative emissions, both for the novelty of many proposals of atmospheric carbon capture and storage, for example, safe carbon storage capacity.
Although a number of scenarios identified in the last decade underestimated the development of renewable energy technologies, now it is possible to define by consensus in the available scientific literature that in the absence of effective, large-scale capture and subsequent storage of airborne carbon, strict emission reduction regulations may be out of reach. The absence of an efficient and deep, de-carbonization of energy as well as industrial sectors, carbon emissions in the future, and in view of emissions that have already happened, will lead to an irreparable impact on the climate for several decades.
Stefano Caserini and colleagues at Politecnico di Milano in Italy described the energy and environmental evaluation of a new process for the storage of liquid carbon dioxide in glass capsules into the deep seabed. They also performed a preliminary evaluation of the costs of a Submarine Carbon Storage plant. Their research work is published in International Journal of Greenhouse Gas Control.
The study presented an energy as well as environmental evaluation of a new method for the storage of liquid carbon dioxide in glass capsules on the deep seabed. The approach was proposed as a safe path for carbon dioxide capture from flue gas of industrial processes as well as power plants, and directly from the atmosphere. This was in order to overcome the obstacles that limit commercial deployment of other carbon dioxide storage methods including injection in saline aquifers. By storing the liquid carbon dioxide separated from the seawater, the proposed method may be a safe alternative with fewer risks associated with carbon dioxide storage in the marine environment.
As of the preliminary cost analysis and Life Cycle Assessment performed in their study, greenhouse gas penalization as well as cost of submarine carbon storage was comparable or slightly higher as compared to alternative storage solutions currently being developed. The research team also observed that the expected environmental risks suggested that the carbon dioxide confinement within the glass capsules had the capacity to minimize the risk linked to carbon dioxide storage in the marine environment.
The preliminary evaluation of the overall cost of the storage with the technology indicated a value of $17/ton carbon dioxide and a rage of 12-30$/ton carbon dioxide. This was competitive with other conventional storage technologies.
The proposed glass capsule technology presents an alternative to the typical storage proposals that are facing challenges in their deployment.
Stefano Caserini, Giovanni Dolci, Arianna Azzellino, Caterina Lanfredi, Lucia Rigamonti, Beatriz Barreto, Mario Grosso. Evaluation of a new technology for carbon dioxide submarine storage in glass capsules. International Journal of Greenhouse Gas Control, volume 60 (2017), pages 140–155.