“By launching Australia’s Global Carbon Capture and Storage Institute earlier this year”, the editorial intoned, “Kevin Rudd recognised that coal would continue to be our major source of power for decades to come …
“However much environmentalists might wish otherwise, the International Energy Agency expects that as overall energy demand increases by 40 per cent over the next 20 years, the share of electricity generated from coal will rise from 41 per cent to 44 per cent. Such realities make the development of carbon storage imperative if greenhouse emissions are to be cut …”
And if overwhelming evidence points to CCS being quite the wrong choice, completely incapable of doing the job?
Well, we’re not to contradict the International Energy Agency. We’re to abide by the wisdom of the coal industry, while apologising to our grandchildren if they’re condemned to lead short, miserable lives.
Technically speaking, and as coal industry spokespeople stress, the laws of physics do not rule out CCS. After all, huge quantities of carbon dioxide have stayed locked up in the Earth, along with natural gas, for hundreds of millions of years.
The problems
The problems faced by CCS are different. Essentially, they are those of carrying out a gargantuan industrial undertaking, to exacting standards, within the briefest of timeframes, in ways whose costs in money and energy do not make the whole exercise absurd.
In the exhaust gases from today’s power plants, carbon dioxide rarely makes up more than 13-14%. The rest is mainly nitrogen from the air. Pumping vast quantities of nitrogen underground is not advocated by even the most enthusiastic supporters of CCS.
That leaves two choices. You can separate out the carbon dioxide from the other flue gases, or ensure the gases are virtually all carbon dioxide by burning the coal in near-pure oxygen.
Usually, carbon dioxide is “scrubbed” from gas streams using organic chemicals called amines. When heated later, the amines yield up the carbon dioxide, and can be recycled. This method is expensive and not very efficient, but the equipment can at least be “bolted on” to existing power plants.
Or you can start by “gasifying” the coal, heating it and reacting it with steam. This creates a stream of hydrogen and carbon dioxide. The hydrogen can be separated off and burned to produce electricity, while the carbon dioxide is piped off for storage underground.
This is the method planned for the experimental “FutureGen” plant in the US. Proponents of FutureGen claim the plant will have close to zero emissions, though costs will be far higher than for conventional coal power.
Alternatively, you can burn the coal in oxygen. But obtaining near-pure oxygen beforehand requires what is, in effect, a separate energy-hungry chemical plant.
Whichever method you choose, your electricity is no longer cheap. As New Scientist reported on March 29, 2008: “The US government reckons CCS will increase the cost of coal-fired power generation by 75 per cent.”
That puts coal-fired power with CCS in much the same price range as wind power. Modelling suggests that solar thermal will eventually be substantially cheaper.
Taking all their life-cycle energy costs into account, wind and solar have relatively small “carbon footprints”. By comparison, “clean coal” stomps across the countryside; mining and transporting coal uses large amounts of energy. New Scientist goes on to note: “The most detailed published assessment, by Peter Viebahn of the German Aerospace Center in Stuttgart, estimates that at best CCS will reduce greenhouse gas emissions from coal-fired power stations by little more than two-thirds.”
Continuing to emit this much carbon dioxide into the atmosphere cannot even be contemplated. Climate science now tells us that we are on a strict budget as to the total carbon dioxide emissions that are allowable in coming centuries.
Even a small fraction of the carbon dioxide that would be released if humanity were to take the CCS route would soon blow our quota. We would still get our catastrophe, just a few years further along the track.
This makes the complexities and costs of burying the carbon dioxide somewhat beside the point. But let’s allow ourselves a few observations.
Pipes
First, the pipes. New Scientist explained: “A study by the International Energy Agency suggests that the (European Union) would need 150,000 kilometres of pipeline to trunk its CO2 emissions to the North Sea.”
Three times around the world — and that’s just for Europe. Gas pipelines are made of steel, and steel-making releases large quantities of carbon dioxide.
Gases, meanwhile, are transmitted along pipelines at high pressure, which requires energy for the pumps. Then the carbon dioxide has to be injected, at still greater pressure, into deep rock strata. More energy, more emissions.
Would the carbon dioxide stay underground? In good sites, such as depleted North Sea gasfields, probably yes. But the monitoring would have to be forever. And as the September 7 Sydney Morning Herald said: “The cost of CCS is generally considered prohibitive if the distance to injection of captured CO2 exceeds 100 kilometres.”
The political pressure to use less-than-satisfactory geological structures would be immense.
All this has to be understood in the context of new science that dramatically re-evaluates the situation in which plans for CCS are being mapped out. Writing in the British September 1 Guardian, George Monbiot described a series of studies that together show the priority in combating climate change needs to shift to making the greatest possible emissions cuts in the short term.
Carbon dioxide, the scientists concluded, is much more persistent in the atmosphere than previously thought. Of the carbon dioxide produced by humans this century, around 40% will remain in the atmosphere at least until the year 3000.
If emissions cuts are now put off for decades — until, for example, CCS is in large-scale operation, or large numbers of nuclear power plants are built — high carbon dioxide levels will build up in the meantime. Even if all emissions then cease, these peak levels will decline only very slowly.
No going back
The accumulated carbon dioxide will raise global temperatures, and here, the scientists report a further crucial finding. Thanks to the ways in which oceans absorb heat from the atmosphere, temperatures are then expected to “remain approximately constant … until the end of the millennium despite zero further emissions”.
At whatever point temperatures peak, Monbiot explained, “that is more or less where they will stay. There is no going back.”
Along with big economies in energy use, quick cuts in emissions will require crash programs aimed at exploiting the renewable energy sources that are available now, or are likely to be ready within the next few years.
That points to wind, solar thermal, biomass, small hydro, conventional geothermal and the new “CETO” wave energy technology. “Hot rock” geothermal, the first examples of which are operating in Europe, may also make the cut.
But CCS is still decades away and requires the smelting of huge tonnages of metal for the pipes. Forget it. The same applies to nuclear, with its long design and construction times.
Needless to say, the stark new evidence Monbiot outlined finds no place in the editorialising of the Australian. That is not to say the Murdoch journalists and editors are ignorant of the new findings.
This much is proved by the fact that Monbiot published his summary in the Guardian. Writers for the Australian scour the pages of this left-liberal British newspaper, going on regularly to snipe in print at errors or ineptitudes of their ideological competitors.
In any case, scientific evidence has nothing to do with the campaign for CCS. “Clean coal” is the kind of proposition that would never be canvassed seriously if powerful corporate interests did not need it as political cover.
Failing to get the climate question right will, of course, have truly horrifying consequences. Conceivably, that might cause twinges of conscience in champions of “clean coal”, including those in the editorial offices.
But more likely, progress into the executive suites required these people to dump their consciences long ago.
www.greenleft.org.au/2009/812/41773
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Can renewables re-power Australia? By Renfrey Clarke (Green Left Weekly)
"Forget ‘alternative’ energy — it can’t work!" That — and in almost those exact words — was among the messages of an article published in the Rupert Murdoch-owned Weekend Australian by journalist Terry McCrann.
Wind power in particular, McCrann assured us, was "useless". And the proof? "In a brief but utterly devastating analysis”, McCrann said, "Andrew Miskelly and Tom Quirk tracked the power output of all the now quite substantial wind farms in South Australia, Victoria, NSW and Tasmania for every minute of June. The simply devastating conclusion: when the wind don’t blow, it don’t blow everywhere at the same time.
"This utterly shreds the claim that if you build enough wind farms nationally the wind will be blowing somewhere. You have to keep fully equivalent coal power up and running, not just when the wind is not blowing, but all the time."
Actually, the above-noted study does nothing to disprove the fact — well demonstrated by studies in the US and Spain — that widely dispersed wind farms with modest back-up from other energy sources can provide round-the-clock "base load" power.
Data collected by Miskelly and Quirk during June 2009 showed the total output of 11 Australian wind farms was close to zero on about six occasions, for a total of about 100 hours.
However, the electricity measured was mostly from large wind farms grouped in a relatively small area in western Victoria and south-eastern South Australia — not far apart and subject to different wind conditions. There was only a small input from NSW wind farms in the study.
Meanwhile, McCrann’s claim that wind power needs to be matched at all times by coal-fired power proves just one thing: he knows nothing about energy generation.
When the wind doesn’t blow, there are various options for taking up the slack. One is to use hydropower, which can be brought into operation almost instantly. For the most part though, Australian grid controllers prevent outages by using gas-fired power as back-up.
This reserve equipment has to be in place whether you use wind or not, since fossil-fuelled plants suffer breakdowns from time to time. Typically, coal-fired plants are shut down for repairs and maintenance about 10% of the time. This compares with less than 2% for modern wind turbines.
Energy authorities, of course, know perfectly well that a large high-pressure system can bring relatively light winds simultaneously to most of south-eastern Australia. The resulting lulls in wind power can usually be forecast days in advance. That’s time enough to take countermeasures — including, in extreme cases, temporarily firing up mothballed coal-burning plants.
However, the most obvious point ignored by the Australian is that wind power is not the only form of renewable energy — it’s just the one that’s now most developed and cheapest.
Future electrical grids will be much more diversified. Lulls in one renewable energy source can be made up by robust output from others.
Consider wave power. In the strong, constant swells of the Southern Ocean, Australia is reckoned to have the world’s largest and most consistent wave energy resource. Along lengthy stretches of Australia’s southern coastline, wave heights rarely fall below one metre. That is base-load energy waiting to be tapped.
After a decade of development at Fremantle in Western Australia, Carnegie Corporation’s CETO wave technology is now at the pre-commercial stage. Finance is being sought for a demonstration wave farm and negotiations are under way for test sites.
CETO uses the action of waves on submerged buoys to work pistons anchored to the seabed. High-pressure seawater is piped ashore where it powers turbines that generate electricity.
Costs are predicted to be similar to those for wind power at good sites. When demand for electricity is low, the high pressure can be used to desalinate seawater.
Still more revolutionary, arguably, is solar thermal technology that has been developed over more than 30 years by engineers and scientists at the Australian National University (ANU) in Canberra.
Solar and wind power have long been recognised as complementary to one another. When winds during the day are light, the odds are high that the sun will be shining brightly.
Near Whyalla in South Australia, a plant is being built that will further test the ANU designs.
The installation will feature large solar mirrors, able to track the sun and concentrate its rays up to 2000 times. Four 500-square-metre "Big Dishes" will create maximum temperatures of more than 2000ºC, several times hotter than advanced fossil-fuel generating plants.
As well as opening new horizons for solar electricity generation, the equipment has potential for use in ultra-high-temperature industrial processes.
ANU’s technology also promises to overcome the dual scourges of solar power — nightfall and cloudy weather. The intense heat of the Big Dishes will be used to heat ammonia to separate it into nitrogen and hydrogen. These two gases can be stored for as long as needed and retain most of the original energy.
Solar power will thus be turned into gas-fired power — available at any time.
The initial stage of the Whyalla project, to cost $15 million, will start operating in mid-2010. About $350 million will then be sought to build a 600-dish, 80 megawatt solar thermal plant.
Estimated electricity costs for the new system have not been released. But the technology appears to have important advantages compared with competing solar-thermal power systems — whose costs are predicted eventually to undercut those of fossil fuels.
The Big Dishes have been designed for cheap mass production and the ammonia process is described as suitable for large-scale solar fields of 500 megawatts or more. The potential for using the dishes with other high-temperature processes could also be an important factor helping to cut costs.
Not only might this world-leading technology allow Australia’s vast solar power resource to be used to replace fossil fuels, but it could also become a big export earner within a few years. Certainly, it seems a better investment than “clean coal”, which is to receive hundreds of millions of dollars in federal funding.
Curiously, ANU’s Big Dishes remain little-known, even among renewable energy enthusiasts. The main Murdoch publication in South Australia, the Adelaide Advertiser, has referred to them in only a few small, cursory reports.
The Australian, so far as this writer can tell, has published nothing. But considering the close ties between the Murdoch empire and the coal industry chiefs, that is not so surprising.
Green Left Weekly: www.greenleft.org.au/2009/809/41613
www.greenleft.org.au/2009/812/41773
