Ask our panel of experts, including scientists & economists

Definitely, and there are many exisiting commercial and industrial uses for large quantities of captured carbon dioxide emissions.

For example, the use of CO₂ in building materials, especially concrete, is well advanced and represents a promising method of sequestering carbon dioxide, rather than venting it out in the atmosphere. CO₂ is also used in the manufacturing of chemicals and pharmaceuticals, in Enhanced Oil Recovery (EOR), and as an aid in the growth of plants and vegetables. More recently, CO₂ has been used to grow an algae that can be converted into biofuel for use in transport vehicles.

Finding ways to sequester and re-use captured CO₂ emissions will play an important part in preventing serious climate change. Therefore, we can expect to see continued, and intensive, research and development in this area.

 

Answered by Dr Thomas Berly Australian Coal Assoication

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Absolutely. This is pre-requisite to any CO₂ being injected underground. Storage proponents are required to secure land access through extensive consultation with landholders guaranteeing safe and sustainable CO₂ injection.

Answered by Dr Thomas Berly Australian Coal Assoication

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Absolutely. CCS doesn’t only apply to coal-fired power plants. CO2 can also be captured, transported and stored from energy-intensive, high-CO2 emissions industrial processes (e.g. cement and steel production) as well as from natural gas-fired power plants.

Answered by Dr Thomas Berly Australian Coal Assoication

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An old sub-critical retrofitted coal fired power station capturing and separating almost all the CO₂ from its flue gas will require approximately 30% more energy of the total energy produced by the plant.

For a new Post-Combustion Capture (PCC) equipped power plant with good integration of steam heating to the stripper (where CO₂ is captured), the energy penalty could be as low as one-fifth (or 20%) of the total amount, using currently available PCC technologies.

Other capture technologies currently in their testing stages, such as Oxyfuel and Pre-Combustion Capture, are projected to have even lower energy penalties.

Additional energy required to transport and compress CO₂ captured from power plants will add an extra 5-10% depending on the distance between the source and the sink.

However, if the additional energy for capturing, separating, transporting and storing CO₂ was derived from renewable technologies such as wind and solar, it would be entirely possible to have a reliable, secure, and economically sustainable source of coal fired energy with near zero emissions.

Answered by Burt Beasley (ACA), Peter Cook (CO2CRC), Dr Thomas Berly (ACA)

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CO₂ storage sites are very carefully selected and are generally chosen against criteria such as relatively low seismic activity and are usually some distance from any active fault systems. However in some tectonically active parts of the world like Japan or New Zealand, suitable CO₂ storage sites can be found much closer to potential earthquake zones.

On the 23rd of October, 2004 The Nagaoka CO₂ storage and monitoring Project in Japan experienced an earthquake during its CO₂ injection trial that registered 6.8 on the Richter Scale. Injection was stopped immediately and the site was monitored for possible CO₂ leakage, however, no leakage was detected. On Dec 6, 2004, the injection of CO₂ recommenced and total of 10,400t of CO2 has been safely stored at the site. This shows that a large earthquake in close proximity to a CO₂ storage site should not result in leakage as long as the site is well characterised and properly monitored.

Finally, remembering that CO₂ is stored in porous rock overlain by an impervious cap rock, any unforeseen breaches in the storage surroundings could only result in a very small (practically undetectable) amount of leakage over a very long period of time. Therefore, a breach in a CO₂ storage site could never pose an immediate or catastrophic threat to its surrounding environment.

Answered by Dr Thomas Berly, Technology Manager, ACA Australian Coal Assoication

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The observed changes in climate, especially temperature increases since about 1970, cannot be explained solely by natural causes such as solar activity.
 
The present atmospheric concentration of carbon dioxide has not been exceeded for the past 650 000 years, and possibly not for 20 million years.
 
Ice core records show that carbon dioxide levels in the atmosphere varied between 180 and 280 parts per million (ppm) depending on glacial cycles.
 
For the past 10 000 years global atmospheric carbon dioxide has been quite stable at between 260 and 280 ppm, and level at about 280 ppm from 1 000 to 250 years ago.
 
Human activities, such as burning fossil fuels (coal, oil and gas), land clearing and agricultural practices have increased carbon dioxide concentrations by more than a third (to approximately 380 ppm), nitrous oxide levels by about 19 per cent and methane concentrations have more than doubled.
 
When only natural factors, such as volcanic aerosols and solar activity, are included in computer models that simulate past and future climate variations, the simulations do not explain the observed warming in the second half of the century.
 
The warming in the second half of the century can only be explained if human-induced changes in greenhouse gases are included in the models.

For more information visit the CSIRO website.

 

Answered by CSIRO

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Given that over 80% of Australia's electricity production is derived from coal, if we were to stop using coal altogether we will have a significant energy supply problem. Renewables have an important part to play, and the ideal solution is to find the right mix of resources that will provide a secure supply of energy with minimum impact on climate change.

Answered by Dr. David Harris CSIRO on Thursday 04 December 2008

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The process of injecting carbon dioxide deep underground has been in operation for decades. First introduced as an effective method of enhanced oil recovery, the technology is now being adapted to geosequestration projects around the world with the emphasis on mitigation of CO₂ emissions. The use of CO₂ for enhanced oil recovery continues to take place commercially in the US, Turkey, Trinidad and Canada and, with the introduction of CCS technologies, an increasing number of these plants are using captured CO₂ from industrial waste streams, rather than naturally occurring CO₂ taken from underground deposits.

There are several projects that have successfully stored CO₂ underground. Here are some examples of successful CO₂ storage:

Sleipner (Norway) – 10 million tonnes This project was the first large scale commercial application of CO₂ storage in a deep saline formation in the world, and has been operating successfully since 1996. It is expected some 20 million tonnes of captured CO₂ (separated from natural gas using amine technology) will be injected and stored over its lifetime.

In Salah (Algeria) – 2 million tonnes In Salah is a full-scale CO₂ capture project at a gas field. Compressed CO₂ is injected into a large underground formation 1,800 metres below the surface, and around 1 million tonnes of CO₂ will be stored each year, with a total of around 17 million tonnes over the life of the project.

Weyburn (Canada) – 10 million tonnes In 1997, the Dakota Gasification Company began transporting all of its waste gas (96% CO₂) through a pipe-line to the Weyburn oil field, where it is then pumped into injection wells to help oil flow toward active producer wells. It is anticipated that about 30 million tonnes of CO₂ will be stored 1,400m underground over the lifetime of the project. 

CO2CRC Otway Project (Australia) – 30,000 tonnes Compressed CO₂ from a natural source has been transported and injected into a nearby depleted natural gas field where it is being monitored by the CO2CRC. It is estimated 100,000t of CO₂ will be injected over 1-2 years and monitoring and modelling will continue, post-injection, for several years after.

CO₂ Sink-Ketzin (Germany) – 60,000 tonnes This project involves the injection of CO₂ into a saline formation and the development of an in-situ laboratory for CO₂ Storage.

For more information on storage projects, visit our website.

Answered by CO2CRC on Thursday 27 November 2008

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Carbon dioxide occurs naturally in the earth's subsurface. In this video Dr John Wright, Director of the CSIRO's Energy Transformed Flagship discusses the safety of storing carbon dioxide underground.

Answered by Dr John Wright CSIRO

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In this video Dr Kelly Thambimuthu, CEO of the Centre for Low Emission Technology, discusses the importance of retrofitting existing coal-fired power plants with carbon capture and storage technologies in order to achieve worldwide reductions in carbon dioxide emissions.

Answered by Dr Kelly Thambimuthu Centre for Low Emission Technology

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Carbon capture technologies enable the CO2 produced from the burning of coal to be captured rather than released into the atmosphere. In this video, Burt Beasley from the Australia Coal Association offers an introduction to capture technologies and what they can achieve.

Answered by Burt Beasley Australian Coal Association

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When coal is burnt it produces carbon dioxide, a greenhouse gas. In this video Dr John Wright, Director of the CSIRO's Energy Transformed Flagship explains the impact the burning of coal has on climate change, in particular when used for power generation.

Answered by Dr John Wright CSIRO

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