The recent decision by World Wide Fund for Nature (WWF) and the Climate Institute to support carbon sequestration and storage (CCS) will set back Australia's efforts to confront climate change, as well as increasing the costs of doing so.
CCS technologies attempt to capture carbon dioxide (CO2)from the waste stream of coal power stations and transport and bury it in underground reservoirs.
The problem with CCS, in a nutshell, is that it is too little, too late, too expensive, too risky, and it displaces other solutions that can do the job.
As our views of the science of climate change have advanced, they have provided sobering news that we are approaching tipping points in the climate system.
If our continued emissions fuel warming of more than a couple of degrees, that is likely to commit us to irreversible melting of the Greenland and West Antarctic ice sheets. That, in turn, locks us in to sea level rises of tens of metres at rates, foreseeably, in the range of several metres per century.
Because of the inertia in the energy and climate systems, we must begin to reduce carbon emissions now if we are to avoid crossing a tipping point. We don't have the luxury of waiting another decade or two to start doing this. Because emissions reductions must start now, the basis of solutions is in those technologies and processes that can deliver immediate reductions and offer the potential for permanent replacement of coal as an energy source.
Our best prospects in this regard are renewable energy, efficiency measures, and emissions reduction efforts and infrastructure changes. Renewables can be implemented now and will scale up with time and become cheaper as they are widely commercialised and research and development increases their efficacy.
CCS has very few of the attributes needed to provide a solution and moves us in the wrong direction. CCS is still in the testing phase and will take a decade or two before it can be implemented in actual working power plants, and then still further decades before it could be scaled up to operate on large numbers of coal plants around the globe. That is too late to change the course of our energy system away from carbon, and too late to prevent emissions crossing a tipping point.
Demonstration CCS projects all plan to operate close to underground storage sites. One of the problems of scaling up CCS is that most coal power plants are not near appropriate storage sites and so very expensive infrastructure would need to be built to transport the captured carbon dioxide. This means that costs of CCS will increase as it is scaled up and the transport infrastructure costs mount.
Australia is typical in this regard in that it does not have appropriate storage sites near some of the key coal plant regions. There are no appropriate storage sites within 500km of the major coal plants in NSW for example. Australian research indicates that transporting CO2 over distances exceeding 100km could be prohibitively expensive.
Too expensive
CCS is too expensive. It will substantially increase the cost of building coal plants (perhaps a near doubling of plant cost, according to the US Department of Energy) and therefore increase the cost of electricity also. The energy required to remove CO2 from the coal plant stream is also substantial and would consume up to 40% of the energy used by the plant.
Thus, coal plants fitted with CCS would require more fossil fuel inputs, and the prices of these inputs can only increase as time goes on and carbon is more fully costed.
Therefore, CCS works to make our energy supply more expensive and more wasteful as we go on and commits us to further dependance on coal.
By contrast, renewable energy will get cheaper as time goes on, and likely would long have outcompeted CCS by the time CCS could be implemented on a commercial scale. Those countries that choose CCS will be locking themselves into expensive energy futures. They will have missed the renewables boat and face rising costs in coal plant commitments. Their economies will suffer because they invested in old energy and it would take further decades to turn them around.
The US Department of Energy has estimated that any new coal plants built with CCS would use about twice the water for operation as existing plants. Water is already a limiting factor in the operation of coal plants in Australia. With increasing stress on our water supplies due to climate change and population growth, we can ill afford a technology that guzzles far more water for power. By contrast, renewables and efficiency require little or no water and will free up water supply as they displace coal plants.
CCS is risky whereas renewables and efficiency carry very little risk. The CO2 from CCS must be stored underground and there is no guarantee that it won't leak. Even small leakage rates back into the atmosphere undermine the point of capturing the carbon dioxide in the first place.
The risks of leaks rise as CCS is scaled up, as the most promising sites would be utilised first, leaving increasingly leaky sites for the widespread implementation of CCS schemes. Leaks from buried carbon stores may contaminate ground water, and surface leakage poses a health risk and may damage ecosystems.
The costs and risks of CCS will be passed on to the public, whereas renewables and efficiency aren't exposed to these costs and risks. The costs of research and testing of CCS are being borne in substantial part by the taxpayer, not by the already heavily subsidised coal industry. Australia subsidises coal over renewables research by a huge margin and the gap is increasing. The risks of long-term storage of CO2 are so great that no company will take on the liability and many are seeking to limit their legal liability to a mere 10 years.
That means that the public will ultimately pick up the tab for the real risks associated with this technology.
The flagship CCS project in the US collapsed on cost grounds despite receiving over a billion US dollars in public funds and receiving protection from financial and legal liability in the event of accidental releases of carbon dioxide. Through CCS we will be creating a global network of potentially contaminated and leaky sites that fall on the public purse.
CCS provides a means for the coal industry to continue reaping the profits while passing on the risks and costs to the public.
Supporters of CCS argue that it is one solution among many, and is needed because renewables and efficiency alone will be insufficient to meet the climate challenge.
This argument ignores both the real costs and opportunity costs of CCS, and the long delays, which render it impotent in the short term and redundant in the long term. Australia has abundant and sufficient resources of solar, geothermal and wind energy to do the job, and the potential to save vast amounts of energy in real efforts at efficiency and the transformation of our cities to sustainable urban forms.
CCS delays action to reduce emissions at a time when we can no longer afford to wait, and it displaces those solutions that can work now and have a lasting impact. WWF's notion of so-called "clean coal" is an oxymoronic vision of Australia's energy future that will derail real efforts to confront climate change if we let it.
[Dr James Risbey is a research climatologist from Tasmania.]