Injection to save the health of our planet?

A state-of-the-art high pressure, high temperature and large scale test rig for geological sequestration, mining and petroleum engineering advanced research works.

With so much talk of climate change, it is not surprising that renewable energy and emission reduction technologies are some of the most talked about areas of research in the world today.  Monash is taking the lead in many areas within this field and one of our researchers, Ranjith Pathegama, has recently been awarded a prestigious Australian Research Council Future Fellowship for his work on carbon geo-sequestration.  One of three to be awarded within the Engineering Faculty, the Fellowships are granted to leading research projects in key sectors, in an effort to promote Australia as an innovation leader.

Doctor Ranjith’s work is primarily focused on the geo-mechanical challenges of injecting carbon into subsurface geological formations, a process known as carbon geo-sequestration.  Whilst simple in principle, the idea of storing large amounts of carbon dioxide in underground reservoirs is somewhat more complicated in application.  As he explains, “if this technology is to become a powerful force in the fight against climate change, it is crucial to have a thorough understanding of how rock formations will behave when high pressure CO2 is injected.”  CO2 can be injected into either coal or sedimentary rock layers, but in either case, the process must be controlled to ensure the high pressure gas does not crack the surrounding rock structures which could lead to uncontrollable leaks.

A second area of Ranjith’s work is looking at highly advanced models for predicting the storage capacity of underground reservoirs.  Current models do not agree well with what is observed in practise and if this technology is to be introduced on a large scale it will be imperative to know how much gas can be safely injected into each reservoir.

Ranjith and his team use start-of-the-art geological research and test facilities here at Monash to investigate what conditions are best suited to carbon storage in subsurface geological formations, several kilometres beneath the earth’s surface.  This enables them to gather very accurate data about how CO2 moves through rock structures depending on local porosity, pressure and other geological conditions.

Current estimates suggest that in a complete carbon sequestration system, storage infrastructure would typically only account for around 10-15% of the total system cost.  “Carbon capture, separation and transportation still account for the bulk of the budget, highlighting the need for cheaper technologies to be developed,” says Ranjith.

He stresses however that carbon sequestration is not the Holy Grail in the fight against climate change.  “There is no one perfect solution,” Ranjith explains.  “The only way we can combat this huge problem, is with a range of different technologies that include carbon capture and storage, renewable energy sources, more efficient energy use and emission reduction.”  Still he warns, “the most important tool is one we already have at our disposal and that is a fundamental change in mentality about the way we use energy.  Consuming energy like we are today is just not sustainable.”