Carbon Capture

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Carbon sequestration is an approach to mitigate global warming by trapping carbon dioxide emitted from power plants in underground sites. It is a new technology with uncertain benefits and very little experimentation into. Australia's pioneering of this underground carbon storage facility will certainly be beneficial to further studies in this area.
Australia's first underground carbon storage facility has opened in the southern state of Victoria.

The geo-sequestration plant, the only one in the Southern hemisphere, will capture CO2 from a power station and store it 2km below the surface.

Researchers believe the pilot scheme will help Australia make deep cuts to its greenhouse gas emissions.

Environmentalists, though, are not convinced that the technology is appropriate.

'Very significant'

Australia's new carbon "tomb" lies in an old gas field near the town of Warrnambool, west of Melbourne.

Under this type of geo-sequestration, CO2 (carbon dioxide) from power plants is compressed into a liquid and pumped underground.

Several years of testing have convinced scientists that the site in southern Australia will be able to safely absorb 100,000 tonnes of greenhouse gases.

Rock formations have been described as giant sponges that will soak up the CO2. The hope is that the dense fluid will remain locked away indefinitely.

One of the project's chief architects, Dr Peter Cook, says the technology will be carefully scrutinised.

"What we'll have is probably the most comprehensive monitoring programme for stored CO2 anywhere in the world," he said.

"It will also be one of the largest pilot projects in the world.

"It's a very, very significant project even by world standards and we're having a number of international groups who'll be working with us as part of this experiment.

"So, it will be the first real test of geo-sequestration under Australian conditions."

The scheme has the support of the Australian government and the country's powerful coal industry, which is looking at ways to secure a greener future.

A senior chemical engineer has told the BBC that geo-sequestration should be an effective way to curb CO2 emissions if leaks from underground storage areas can be avoided.

There is a warning, though, that this controversial process is expensive.

Environmental groups believe it has too many unknowns.

They have insisted that the money spent on the Victorian project should have been allocated to proven technologies, such as solar and wind power.
Fossil fuel dependency
While carbon sequestration solves the problem of carbon emissions into the atmosphere, it certainly will not aid in reducing the fossil fuel dependency of nations. In fact, it threatens to exacerbate the problem.

Not only does it not reduce the fossil fuels consumed, but it also requires additional fossil fuels to power the process of sequestering the carbon dioxide. Estimates are at 11-41%, an amount that is unlikely to decrease much.

Thus in reality, carbon capture may be a technology that helps combat global warming, but it still doesn't deal with another equally pressing problem -- the depletion of natural resources.

There is really no point investing in new technology that is inherently dependent on natural resources if these natural resources are going to deplete soon. Such money can be better invested in renewable energy such as solar or wind technology.

What about the rising oil price and the unstable Gulf region? If these power plants depend on oil, the problem could be even more disastrous. The rising oil price is the result of excessive demand, something an energy intensive activity like carbon sequestration would certainly contribute to. If economic instability is the goal, then by all means, convert to carbon sequestration. But if it is to be shunned, then the choice is clear -- stick to renewable energy.

Geographic limitations
Another problem with this technology is that it can only be used where there are appropriate carbon "tombs" that can hold the carbon dioxide safely and that can be used for a sufficiently long time such that the initial costs are covered. Yet, can such carbon "tombs" be found anywhere and everywhere? Oil and gas fields, saline formations, unminable coal seams, and saline-filled basalt formations have been suggested as storage sites. For countries, or specific regions within these countries to be precise, that lack such storage sites, does it then mean that this technology is useless?

Some have also suggested ocean storage. The problem with this is two-fold. Firstly, CO2 causes the acidity of the water to change, killing many ocean organisms. Secondly, dissolved CO2 would eventually equillibrate with the atmosphere, so the storage would not be permanent. Landlocked countries aside, this isn't an ideal solution either.

With so many geographical limitations, carbon capture really doesn't sound too ideal to me.

On a side note, Singapore's was beaten flat by Australia in the pioneering game. Eat that Lee Kuan Yew.







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