'Clean coal' - a dirty lie

October 26, 2007

If you've sat in front a TV in the past few weeks, you'll have seen the message: Australians need to get "climate clever" just like the Howard government, which, we're told, is encouraging and funding new, environmentally friendly technologies such as "clean coal". In fact, we're led to believe, the government has put some $3.5 billion in recent years into new methods for combatting climate change.

We're not supposed to be sharp enough to pick the latter claim as a deception. In fact, $3.5 billion was not invested by the government at all, but by private business, responding to the incentives set in place by the government's Mandatory Renewable Energy Target scheme.

Nor are we told that, for more than two years until September, the federal government refused to maintain these incentives at a meaningful level. In the meantime, investment in renewable energy has stalled, leading the Wind Energy Association and the Business Council for Sustainable Energy to angrily criticise the government for its inaction.

There's no doubt, though, that PM John Howard and his government are right behind "clean coal". A June 19 editorial in Rupert Murdoch's Australian argued that "Australia and [the world's largest resource corporation] BHP Billiton have a shared interest in developing economically viable, clean coal technology".

"Australia is the world's largest exporter of coal with 30 per cent of the global trade. Not only that, black coal is Australia's largest commodity export, worth about $24.5 billion in 2005-06, an increase of 43 per cent over 2004-05."

The paper might have added that the coal trade is the source of vast profits to people who wield immense influence at the top levels of the government and the Liberal Party.
"Whatever we achieve in terms of the reduction of our own minuscule greenhouse gas emissions, which are 1 per cent of global emissions", the editorial continued, "will be trifling compared to the global reductions that will be possible if we achieve a breakthrough in clean coal technology".

Renewable energy in Australia, the implicit message runs, is not worth spending money on. The real priority, the Australian argues, should be developing ways of burning coal without releasing greenhouse gases.

The trouble is, avoiding runaway global warming will require drastic cuts to global greenhouse emissions to begin within the next decade. What if technical obstacles mean that "clean coal" will not be a reality for a decade beyond that, if ever? What if electricity from "clean coal" finishes up costing more than energy from renewables? Neither the Australian nor the federal government has tried seriously to answer such objections.

Meanwhile, the swelling flood of cheap Australian coal onto world markets lowers international prices and encourages the building of more coal-fired power plants. Australia's contribution to world greenhouse emissions might seem "minuscule", but if coal exports are factored in, this country emerges as a true greenhouse ogre.

With voters increasingly perturbed at Australia's bad reputation on climate-change issues, Howard is banking on "clean coal" to provide a distraction. As depicted by its image-makers, his government refuses to take merely symbolic steps — such as ratifying the Kyoto Protocol — but prefers to actively promote a new, breakthrough technology.

"Clean coal", however, still needs to actually deliver — and the central problem that Howard and his ministers face is that coal is inherently a greenhouse gas-intensive fuel. When burned, it produces the greenhouse gas carbon dioxide.

By contrast natural gas, when it burns, produces mainly water. Generating a megawatt-hour of electricity in a modern pulverised-coal power plant produces about 1000 kilograms of carbon dioxide in the case of the brown coal used in Victoria, or about 800 kilograms in the case of the black coal used in Queensland and NSW. The output of carbon dioxide from a gas-fired plant is about 400 kilograms per megawatt-hour.

As used in public debate, the phrase "clean coal" routinely conflates two distinct areas of technology. One of these involves generating electricity from coal more efficiently, so as to produce less carbon dioxide per unit of power output. The other, referred to as carbon capture and sequestration (CCS), involves taking the carbon dioxide produced by the combustion of coal and isolating it permanently from the atmosphere. Both areas of technology are examined in detail by University of NSW scientist Dr Mark Diesendorf in his recent book Greenhouse Solutions with Sustainable Energy.

In terms of fuel use, the most efficient coal-fired power stations in the world today are a number of pilot plants that employ new and complex Integrated Gasification Combined Cycle (IGCC) technology. No such plants exist yet in Australia. IGCC plants are expensive to build — according to the journal Chemical and Engineering News, around three times as costly as the most efficient gas-fired installations. They are also expensive to run, producing electricity at a cost 20-40% higher than conventional coal plants.

"These are chemical plants", a coal industry expert quoted in the February 23, 2004 edition of Chemical and Engineering News stated. "You've got a cryogenic oxygen plant, a pressurized gasifier, gas cleanup equipment, shift reactors, and a new power system. It's a whole cultural difference."

For all their sophistication, IGCC plants still work by taking coal and turning it into carbon dioxide; the reductions in greenhouse gas emissions they allow are strictly limited. Diesendorf, in his book, suggests a greenhouse intensity for them of about 700 kilograms per megawatt-hour — far above what is needed for genuine greenhouse abatement. "The term 'clean coal'", Diesendorf concludes, "is essentially a marketing tool".

If "clean coal" is not to remain filthy dirty, it needs to be combined with carbon capture and long-term storage. In Australia, the coal industry's research has concentrated almost entirely on geosequestration, which involves capturing the carbon dioxide and burying it underground in depleted oil and gas fields, deep saline aquifers, or coal beds too deep to be mined.

Geosequestration of carbon dioxide has occasionally been practised in the natural gas industry, but is surrounded by a host of unknowns. In order to exist, oil and gas fields must have been covered by impermeable layers of rock. But there are no guarantees that after multiple penetration by drill holes, and operations to increase permeability by hydraulic fracturing, these fields will hold carbon dioxide. Whether the aquifers and coal beds will hold carbon dioxide for many thousands of years is also speculative.

Then there is the question of costs. Carbon dioxide makes up about 14% of the flue gases from conventional power plants. If it is to be removed in order to be stored underground, costly and energy-intensive chemical scrubbing is required. An alternative is to build power plants that burn coal in oxygen rather than air, resulting in exhausts that are more than 90% carbon dioxide. Obtaining near-pure oxygen, however, also involves large additional costs. Unless the power plants are virtually on top of suitable geological structures, gas pipelines must be built. Finally, if drill holes are not already in place in the proposed storages, deep drilling is far from cheap.

In February, the Canberra Times reported that CSIRO carbon capture expert Dr Greg Duffy told a 2006 House of Representatives committee inquiry into geosequestration that carbon capture would double the cost of baseload electricity generation, and reduce the output from a power station by about 30%.

A 2005 study by the Intergovernmental Panel on Climate Change (IPCC) put the cost of electricity from an IGCC coal-fired plant with carbon capture and geological storage in the range of 5.5-9.1 US cents per kilowatt-hour. This is the same range as for the more advanced present-day renewable energy technologies, and considerably more than the predicted cost of "hot dry rock" geothermal energy.
Using IPCC data and his own calculations, Diesendorf concludes that "the projected costs of CO2-free electricity from fossil-fuelled power stations plus CCS may be higher than the current price of wind power at excellent sites and the cheapest options for bioenergy".

Moreover, and as Diesendorf stresses, the cost calculations for coal-fired power do not include the massive social and environmental costs of coal mining. These costs, which include strip-mined landscapes, polluted streams and extensive health damage, are borne in large part by society as a whole.

However the most telling weakness of "clean coal" is not its cost, but its time-lines. Diesendorf notes the "immaturity" of "clean coal" technologies, and quotes a 2004 study that concludes that "CCS technologies could take at least several decades to implement on a large scale".

Pronouncing on "clean coal", Labor leader Kevin Rudd was quoted by the Melbourne Age in March as predicting that electricity from plants using carbon capture and storage would enter the grid by 2030.

The environment, however, cannot wait until 2030. At present rates of increase, the accumulation of greenhouse gases will very likely tip the atmosphere over the threshold of runaway warming well before this date. All greenhouse abatement measures will then be irrelevant.

The prospects for "clean coal" are dim indeed. It is hard to believe that coal corporation executives and key Liberal Party leaders are unaware of this fact. But Howard has nevertheless provided generous amounts of public money to support "clean coal" research. In the first round of grants last year under the government's Low Emissions Technology Development Fund, fossil-fuel interests received $335 million of the $410 million allocated. Four of the six grants approved went to the coal industry for projects involving carbon capture and sequestration.

The position of ALP leaders has been ambiguous. Though pledging to increase incentives to the renewables industry, they have been too cowardly to take on the coal bosses in an all-out political fight.

Instead of condemning the federal government for wasting public money on unpromising and probably irrelevant research, Labor leaders have fallen into their habitual "me too" posture. In March, Rudd released plans for a $500 million National Clean Coal Fund, while in April Steve Bracks's Labor government in Victoria announced more than $9 million in "clean coal" research grants. Commenting on these handouts, Greens Senator Bob Brown remarked, "It's like putting $100 million into developing low-tar cigarettes".

Though alarmed by global warming, the mass of Australians are betrayed and misled by an ecocidal government and a gutless "opposition". It will take a broad political revolt if the country is to escape its present status as prime pusher of cheap coal to an overheating planet.

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