An Australian-led scientists team on Tuesday said that they found carbon dioxide (CO2) could be safely and reliably stored underground.
The team was led by Professor Peter Cook and the research was based at the Cooperative Research Centre for Greenhouse Gas Technologies (CO2CRC) Otway Project in southwestern Victoria of Australia.
It is reported that depleted gas fields would be able to store globally significant amounts of carbon dioxide (CO2) and eventually to strive against climate change. The team set out to determine if the technology was safe and effective under Australian conditions.
"The Otway Project has confirmed that storage in depleted gas fields can be safe and effective, and that these structures could store globally significant amounts of carbon dioxide," the report' s lead author Dr Charles Jenkins, from the Commonwealth Scientific and Industrial Research Organization of Australia, said in a statement.
"The research included the world's first measurement of storage efficiency for CO2 storage, lending weight to the conclusion that depleted gas fields have enough storage capacity to make a significant contribution to reducing global CO2 emissions."
Carbon capture and storage (CCS) involves capturing CO2 from a stationary source, like a power station, and storing it underground. The technology is being developed in a handful of countries around the world but has been controversial, with some projects being blocked.
Cook said the most observable finding was no leaking of CO2 from their carbon capture and storage system.
Earlier in April 2008, the team injected compressed liquefied gas form 2 km below the ground into permeable sandstone in a depleted gas field. CO2 was prevented from moving upwards (and sideways) by a cap of impermeable mudstone rocks overlying the gas reservoir. Over a period of several years, movement of CO2 through the rock was tracked by seismic imagery and fluid sampling.
"The results verify that it is a valid way of cutting down on greenhouse gas emissions, particularly CO2," Cook said.
"Monitoring showed that there has been no measurable effect of stored CO2 on soil, groundwater, or atmosphere."
The conclusion stated that large-scale geological storage can be monitored to ensure safety. No leaking of the CO2 back into the atmosphere.
However, some experts questioned about the cost effectiveness of capturing carbon at large-scale electricity power plants and whether the storage will be stable over the long term. Moreover, there were not enough information about the usefulness of commercial-scale CCS.
The scientists published details of findings in Proceedings of the National Academy of Sciences this week.