Getting clean

HOW clean is the clean coal that coal players argue will help limit greenhouse gas emissions? Charlotte Dudley investigates
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Staff Reporter

Published in the May 2007 Australia’s Mining Monthly

In an effort to clean up its fossil fuel-emitting image, the coal industry is making moves toward cleaner, less-polluting methods of dealing with coal.

The current buzz topic for both industry and politics, clean coal technology (CCT) is generating much attention with debate taking in environmental issues, job protection and the future of economic growth, not to mention the funding that’s been thrown about.

CCT is a generic term for a number of technologies that reduce the harmful emissions produced from burning coal.

While developments are principally focused on the role of coal in power generation, it also takes in efforts to reduce and manage emissions in the extraction and preparation processes, with increasing efforts on the carbon capture and storage front.

Australian Coal Association external affairs director Doug Holden said since the acid rain realities of the 1960s and 70s, steps had been taken to reduce sulphur dioxide (SO2) and nitrous oxide (N2O) levels from coal processes.

Today, the mounting urgency of the global warming issue has led to a recent groundswell of research and development into the area of CCT.

According to the International Energy Agency’s Clean Coal Centre managing director John Topper, the three principal clean coal technologies of pre-combustion, post-combustion or coal gasification methods stand to deliver about a 90%-plus reduction of carbon dioxide.

“So basically they’re almost carbon-free,” said Topper.

The gasification process holds out the promise of zero emissions because all CO2 is removed.

Spelling out the various CCT techniques, the ACA’s Holden said pre-combustion technologies could involve the use of oxyfuel – where coal is burnt in pure oxygen resulting in the more efficient CO2 capture – while post-combustion methods involve “bolt-on” technologies added on to existing power stations to facilitate CO2 removal.

Technologies such as coal gasification produce a fuel gas from the burning of coal, and then stream off CO2 for capture. The resultant gas and waste heat can be used as a further energy source.

Speaking from his home in England, Topper said there was a lot of international interest in clean coal developments from the research and demonstration phase through to the commercial deployment stage.

While it is touted as the “technology for tomorrow”, Topper said gasification processes and carbon capture and storage were already being used around the world.

CO2 capture and storage technology (also referred to as geosequestration) is currently in operation at a natural gas project in Norway and Topper noted the strong trend toward SO2 and N20 reducing technologies and lower emission supercritical power plants in Japan, the US and Europe.

Australia too, has shown its commitment to the development of low emission coal solutions, he said. “In some respects you’re up there alongside the world leaders in terms of trying to develop technology and in trying to look at how you would capture the CO2.”

In Victoria’s Otway Basin, a project is underway aimed at demonstrating the viability of carbon capture and storage. Conducted by collaborative research organisation, the Cooperative Research Centre for Greenhouse Gas Technologies, the CO2CRC pilot program involves the capture of CO2 from power stations and its controlled underground geosequestration.

Other Victorian CCT projects include the Monash Energy project, which is researching the conversion of coal into synthetic diesel, stripping off CO2 along the way.

Similar to the Norwegian gas operation, Western Australia’s Gorgon liquid natural gas project is a non-coal operation looking to demonstrate the feasibility of injecting CO2 into deep formations off the state’s North West Shelf in order to reduce greenhouse gas emissions.

In Queensland, Holden pointed to a number of research and demonstration projects such as the Santos coal seam methane extraction project and the Callide Oxyfuel project that aims to demonstrate CCT through oxyfuel combustion methods at an existing power station.

Climate Institute policy and research director Erwin Jackson endorsed the move toward less pollutant coal technologies but said there needed to be a more rapid development and deployment of the operations.

He said government needed to put in place the policy framework that would enable acceleration of the technology.

“While we do need to demonstrate particular technologies, if we’re serious about the climate change problem, we need to be seeing commercial sale applications of this product very quickly … the sooner we know it works, the better,” he said.

The road toward clean coal technologies is one of research, demonstration projects and testing, refining and proving the technology before ultimately being able to commercially deploy the technology.

Topper said pilot projects generally needed about three years to prove themselves, with commercial deployment of clean coal technologies pegged at around 10 years time.

Holden agreed with Topper’s timeline estimate and said commercial CCT deployment was “going to be in the next decade”, with further activity in the next decade after that. For now he felt industry was heading in the right direction.

“The critical thing first is the sort of research and development projects that we’re doing. You have to deal with the technology in the demonstration phase first. That’s basically what’s happening around the world now.”

Topper expressed confidence that a low emissions coal future would overcome any technical obstacles.

“They’re all doable,” he said of the coal technology options. “Everybody’s very confident that [the technical issues] can be tackled and that over time the costs of introducing those new technologies will come down.”

Holden shared the positive view. “I think the general view is that we are pretty well ahead of the game in terms of the number and breadth of projects that we’ve got underway … and in the amount of money that’s being spent.”

Centre for Low Emission Technology program manager Graham Reed said that in terms of electricity production costs, an equivalent clean coal operation using carbon capture and storage technology would cost about 40% more than a conventional station.

On a purely fiscal level, Reed said clean coal technology was a costlier alternative to traditional technologies but that money was not the only factor. As traditional coal-fired methods offer lower energy efficiency, contribute significantly to harmful greenhouse gases and require a greater amount of fuel to operate, a broader approach to the issue of CCT cost is clearly warranted.

He said that as technology and reliability improved, it was likely the financial cost of CCT would come down, particularly as the technology entered its second generation of development.

Until then, industry is making the most of federal and state governments’ willingness to flash cash for various clean coal projects. A recent round of government grants offered more than $400 million to emissions reducing energy developments, while the ACA’s Holden estimated that both government and industry combined had contributed about $1 billion to CCT projects.

However, money can’t buy everything.

In addition to funding dilemmas and technical challenges, Topper felt there were other issues surrounding CCT that needed to be addressed – for example those relating to the regulation, transport and storage of CO2. He said the successful deployment of CCT also rested on gaining public confidence particularly when it came to the safety and reliability of carbon storage.

Despite calls from some sections of politics, Holden said the coal sector was not shutting up shop. As he saw it, increased energy demands and the emerging economies such as China and India would continue to rely on coal, and developed countries had a responsibility to lay the groundwork for the application of cleaner coal options.

Despite growing acceptance toward CCT, those in the industry supported a diversified approach to energy solutions and were pragmatic about the future.

“There are no magic bullets,” Holden said. “All things are going to be necessary and clean coal is but one part of the suite of things we need to do to make our production of energy more environmentally friendly.”

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