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The future of carbon

The future of carbon
By Ian MacDougall

Before we consider the element carbon, let us first consider that magnificent wonder of Classical Greece, the Parthenon, which was built partly out of it. That is, out of calcium carbonate in the form commonly known as white marble:

[The] Temple of Athena Parthenos (‘the Virgin’) on the Acropolis at Athens; built 447–438 BC by Callicrates and Ictinus under the supervision of the sculptor Phidias, and the most perfect example of Doric architecture. In turn a Christian church and a Turkish mosque, it was then used as a gunpowder store, and reduced to ruins when the Venetians bombarded the Acropolis in 1687. [0.5]

The Parthenon was intact from 438 BC until only 321 years ago. The decision by the Turks then in occupation of Greece to use it as they did is deplored everywhere today, and I dare say even in modern Istanbul. Admittedly though, the Turks did need a store for their gunpowder.

An earlier example of short term thinking and callous disregard for posterity resulted in the deliberate destruction of the great library of Alexandria, probably in AD 272. Much of classical literature was lost forever as a result. [0.55]

However, even these travesties were capped by a decision made one night in 1930 by Wilf Batty, a Tasmanian farmer. Hearing a commotion in his fowl house, Batty reached for his rifle and a short time later shot dead the world’s last known wild thylacine, the marsupial carnivore they called the ‘Tasmanian Tiger’. [0.555]

Today all sorts of suggestions are made as to how thylacines might be reconstituted (at huge expense) from the DNA of pickled museum specimens. But it could be said in Batty’s defence that he was operating according to the conventional rural wisdom abroad in Tasmania at the time. Moreover, he probably believed that both chicken and egg came first.

My following argument is that humanity today is poised on the brink of making a short term political decision so potentially catastrophic in its implications as to dwarf the sum total of all preceding historic blunders. I refer to carbon capture and storage (CCS), at least as presently envisaged.

The best general critique of CCS is that of Greenpeace, entitled ‘False Hope’. [0.5555] The argument set out in that document is that CCS:

  1. cannot deliver in time to avoid dangerous climate change;
  2. wastes energy.
  3. is risky.
  4. is expensive, and
  5. carries significant liability risks.

While generally endorsing the Greenpeace series of arguments, I add two more: (6) that carbon dioxide (CO2) although a greenhouse gas (GHG) and today rightly seen as an atmospheric problem, is none the less a resource that humans in the short term of future historic time will likely see as important for controlling the world’s climate; and (7) that as CO2 is a fundamental nutrient of plants and therefore of the whole biosphere, it is a resource that we cannot afford to waste, particularly as the world population expands and demand for plant and carbon-based products increases, while simultaneously the supply of fossil carbon and its compounds and products decreases.

In the general public and private discussion of the issues relating to climate change, Global Warming and the Garnaut Draft Report [1], reference is commonly made to the ameliorating effect possible through the geosequestration of CO2. This gas is added to the atmosphere by the combustion of carbon-based fuels, and at a greater present rate than can be coped with by the natural systems that remove it from the air. This is arguably leading to dangerous levels in the atmosphere, which the scientific consensus agrees will in turn result, if unchecked, in catastrophic climate change and global warming.

As the reader is probably aware, the CO2 in the Earth’s atmosphere acts in a way that can be likened to that of the glass of a greenhouse, with a net effect of allowing in (higher frequency) incipient solar heat radiation, but allowing less of the (lower frequency) returning radiation to escape. The actual Greenhouse Effect is a bit more complicated, but this net effect remains the same. [1.1]

Most countries of the world have some fossil fuel resources, most commonly coal. But few are exporters. Australia is one of the world’s top six exporters, along with the United States, South Africa, Canada, Indonesia and Colombia. Between them, those countries account for about 80% of internationally traded coal. [2] As coal is now Australia’s biggest single export earner, the Federal Government is eager for a way to be found around the greenhouse problem its end use as fuel creates. Geosequestration of the carbon dioxide, whereby the gas is trapped at the site of production, liquefied under pressure, and removed for burial deep in the Earth at other suitable sites, is seen by the coal industry as the best answer to the problem.

Before we examine that, I would ask the reader to consider the role carbon plays in the makeup of the planet and its biosphere. The masses involved are so huge that the most practical unit to use in discussion is the gigatonne (Gt). (1 Gt = 1,000,000,000 tonnes, or in scientific notation, 1 x 10^9 tonnes, which in longhand is 1 x 10 x 10 x 10 x 10 x 10 x 10 x 10 x 10 x 10 tonnes. A tonne, in turn, is 1,000 kilograms.) A block of bituminous coal 800 metres high and of length and breadth both one kilometre, would have a mass of one gigatonne.

All the world’s land plants together contain about 610 Gt of carbon, chiefly bound up chemically with hydrogen and oxygen in the form of lignocellulose, the major component of their woody and reinforcing tissue. The atmosphere actually contains more carbon (as CO2) than there is in all the land plants put together: 750 Gt are in the air. (The total mass of the atmosphere is about 6,700 times larger than that, at 5.1 × 10^6 Gt. Carbon dioxide is in turn only about 0.04% of the air mass, by what chemists call molar content. [3] It would be exactly the same percentage by weight, and much the same by volume.)

Soils contain a greater mass of carbon still, at 1,580 Gt, which is a bit over twice that found in the air and 2.6 times the total mass in the land plants growing in them. However, this is minor beside the carbon mass in the oceans, which has been assessed at 39,000 Gt (that is, 25 times the mass in the soils). It is made up of living organisms, their shells, skeletons and the limy remains of these lying on the beds of the oceans and seas.

The earliest known fossils of living organisms date from around 3.5 billion years ago. [4] These are stromatolites, or colonies of cyanobacteria (formerly called ‘blue-green algae’). The very earliest living organisms would almost certainly have been something similar to modern ‘chemical-feeding’ chemosynthetic bacteria, rather than to modern photosynthetic cyanobacteria, because chemosynthesis (deriving energy from chemical sources, such as submarine volcanic vents or ‘black smokers’) would have been possible long before photosynthesis was.

Consider now the last in our list of carbon deposits: the rocks. Here carbon is mainly found as carbonate combined with calcium; sometimes also with magnesium, and less often, with such metals as iron, nickel and copper. Because calcium carbonate is so commonly found in association with fossilized life forms, it is reasonable to assume that life has generally been involved in its formation, and from earliest times.

Here also, we come to the major repository of carbon on earth: the rock layer, or lithosphere. Specifically, the carbon is mainly in the sedimentary rocks, which are the most common rocks covering the Earth’s land masses, but only make up about 5% of the Earth’s overall crust. There are 65,000,000 Gt (or 6.5 x 10^7 Gt) of carbon in the rocks. It is found most spectacularly in the vast beds of calcium carbonate (as limestone) which underlie such places as the Nullarbor Plain, but it also occurs as small carbonate cementing particles in many rocks such as shales and sandstones. Put some vinegar on a piece of Sydney or Hobart sandstone and it will fizz, as the calcium carbonate cementing the stone together reacts and releases CO2.

The world really has only one ocean. The total mass of the hydrosphere (ocean, lakes, rivers etc) is about 1.4 x 10^9 Gt [5] and over 98% of it is oceanic salt water. That is, the total mass of carbon in the world’s carbonate rocks and minerals is a relatively huge 4.6% (nearly one part in 20 by mass) of the water in the ocean. If all that carbon was once in the early Earth’s atmosphere as carbon dioxide and methane, and much of the oceanic water was in the air as well as water vapour, that air would have been impenetrable to light. Life would have had to start through chemosynthesis, unless it began at the top of the cloud layer.

To get from the air to the lithosphere, our rock carbon probably spent some time as a component of the primordial ocean. To model that situation, one can take a level teaspoon of Vegemite and fully dissolve it in 19 teaspoons of warm water. The resulting dark liquid is a sample of ersatz primordial ocean. The first chemical feeding bacteria would possibly have converted that rich soup of organic compounds into a swarming population of their descendants. If the chemical feeders did not do it, then the later-evolved photosynthetic cyanobacteria certainly would have. The water of the ocean before life began would have been as if straight out of a pot of minestrone; shortly after life began, as if out of the most slime-infested stagnant pool one can find today. But over the course of evolutionary time, most of its carbon made its way into the bodies of multicellular organisms, then into the carbonate rocks, the oil and natural gas deposits, the land plants and the coal seams of the world. In one of those rare and rapidly transforming events in the history of the Earth, exponential growth of the first populations of photosynthetic organisms would have cleared the ocean water.

It is important to remember, however, that for a while there in the Precambrian (say for at least 1,000 million years after life began) pretty well all of the world’s carbon was probably cycling through the biosphere, with enough locked up in it at any one time to hold the atmospheric CO2 concentration sufficiently low as to prevent the planet from overheating, but at the same time with enough being respired back into the air to prevent the planet from freeze locking. Carbon moved out of circulation and into sedimentary rock would have been replaced, at least in part, by that issuing forth from volcanoes. (Though there seems to have been the odd interlude in geological time when this mechanism gave trouble. [5.25])

The early biosphere, though consisting then of much less complex life forms than we see today, must none the less have been huge by today’s biomass standards. That is something I see as being of crucial significance in dealing appropriately with the present carbon and petroleum resource crises, of which more below.

After the formation of life, photosynthetic cyanobacteria would have steadily removed CO2 from the air and ocean and deposited it as calcium carbonate stromatolites, such as those still found today at Shark Bay in Western Australia and fossilised in the Gunflint Chert of Western Ontario, which was laid down between 2.3 and 1.9 billion years ago. [5.5] Such natural geosequestration has continued to this day.

After the main rock and iron mass of the planet (literally) fell together, the Earth’s primordial atmosphere was likely formed by outgassing of volcanoes. Volcanic gases today consist of around 1.4% CO2 [6]. The atmosphere of Venus is 96.5% CO2 and 3.5% nitrogen [7], and that of Mars is 95.32% CO2, 2.7% nitrogen and 1.6% argon. [8] Titan, which is the largest moon of Saturn, has an atmosphere 98.4% nitrogen, with the remaining 1.6% being methane (CH4) and traces of other gases such as hydrocarbons. [9] It is likely therefore that the Earth originally had just such a ‘reducing atmosphere’, with a larger component of CO2 and significantly greater mass and pressure than the oxidising atmosphere it has now. Its oxygen came only after the first photosynthetic bacteria appeared.

However it must be pointed out that not everyone agrees with this. [10]

The carbon in the carbonate rocks is mainly in the form of carbonate ions, which can be thought of as electrically charged CO2 molecules, each with an extra oxygen atom bonded on. These form when carbon dioxide reacts with water to yield carbonic acid (soda water). Being already in a fully oxidised state, they are not capable of serving as fuel. However, they are used for making cement, and in that process they are strongly heated with powdered shale in kilns, which drives the carbon dioxide out, leaving highly alkaline cement. Once mixed with water and allowed to set, this substance slowly reacts with the CO2 of the air to form calcium carbonate again, over tens or hundreds of years. So all the concrete in the world is a slow CO2 sink.

The carbon we use as fuel was sequestered after the rise of the land plants, the first fossils of which appear in sedimentary rocks of Silurian age (laid down between 443 and 417 million years ago.) [11] But the period of geological time that stands out for coal formation is the Carboniferous (354 to 290 million years ago), there followed, as the race callers say, by the Permian (290 to 248 million years ago). The formation of coal, oil, natural gas and limestone are processes which have never ceased, and can be seen still going on today. Nothing on the face of the Earth or under it is static; everything material is part of some cycle or other. We reading members of the human species are not just passive spectators in the drama of birth, death and decay; we actively intervene in all known processes, and sometimes not even consciously.

How much carbon is in the coal, as distinct from the rocks generally? 909 Gt, of which 479 Gt are high grade (bituminous coal and anthracite) and 430 Gt are sub-bituminous and lignite (ie brown coal). The world’s remaining oil deposits contain another 130 Gt, and natural gas another 110 Gt. As the mass ratio of the carbon in CO2 to that of the whole molecule is 12:44, considerably more CO2 by mass will be produced as compared with the mass of fossil fuel burnt; particularly coal, which is 50-80% carbon. Note also that the 1,150 Gt of total fossil fuel carbon is only one 57 thousandth part of the total carbon in the rocks, which as we have seen, is 65,000,000 Gt. (The carbon statistics above are from a Columbia University source. [11.5])

So the remaining coal reserves contain 79% of the fossil fuel carbon, the oil reserves 11%, and the natural gas reserves 10%.

Had we humans not appeared on the Earth, the great coal seams would have slumbered on deep under its surface, until a time millions of years hence when they were dragged down below the continents in the subduction zones: those fault lines where one crustal plate makes its uncomfortable way beneath another. Their carbon in due course would have transformed into volcanic gas, oil, soot, or diamonds as big as the Ritz; who knows? There has not been enough time passed yet for anyone to find out. Eventually it would all have returned to the air some way or another, to begin its cycle anew. Homo sapiens has just hurried it along a bit, that is all.

What then, should be the future for all that carbon, and right at this instant of geological time, for the carbon dioxide produced everywhere by combustion of fossil fuels?

A few months ago an article in The Australian by Dr Nikki Williams, CEO of the NSW Minerals Council, caught my eye. It was the title more than anything: We can bury carbon dioxide forever. [12] Her major claim I found most intriguing:

Since 1996 at Sleipner in Norway a million tonnes of CO2 a year has been captured and stored 1000m beneath the seabed in the Utsira aquifer. This formation is large enough to store all of Europe's 600 billion tonnes of CO2 emissions for the next 600 years. Since 2000, when monitoring started, there has been zero leakage. The Norwegians are confident that it will remain in situ indefinitely, just as natural gases and oils have remained safely underground for millions of years.

I take her word that Europe will produce 600 Gt of CO2, containing 12/44ths of that mass (164 Gt) of carbon some time in the next 600 years. On the face of it, she is probably right. I also take her word about the confidence of the Norwegians, but that is all I take on that front.

Steve Furnival, a reservoir engineer at Senergy Ltd, in Aberdeen, UK, has written a detailed article [13] on CCS and Sleipner. His aim is to explain how “capturing and burying the carbon dioxide produced could help avert disastrous global warming”, so he does not approach the issue from the Greenpeace end of the arena. He says:

Carbon storage is not just wishful thinking: there is already a successful CCS scheme operating in Norway. The Sleipner gas field was discovered in 1974 and is one of the largest gas producers in the Norwegian sector of the North Sea. However, the gas in the field contains 4–10% carbon dioxide, while typically less than 2.5% is required to ensure the gas will burn properly. In almost any other country, the oil company would have removed the excess carbon dioxide from the gas and vented it into the atmosphere. But under Norway's environmental laws, Statoil – the state oil company – would have faced an annual carbon-tax bill of about $50m for this option. Instead, Statoil researchers investigated storing the carbon dioxide in a nearby geological formation: the saline aquifer called Utsira that lies above the Sleipner field. Utsira is a massive formation: at some 500 km long, 50 km wide and 200 m thick, it has the capacity to store 100 times the annual volume of carbon dioxide emitted from all Europe's power stations. [13]

Now this is a bit tricky, because CO2 comes out of power stations as a hot, low density gas. One assumes that this refers to final liquid volumes of CO2. From the above figures, if it were all hollow space, and the shape of a rectangular prism, the Utsira aquifer would have a volume of 5 x 10^12 cubic metres, or 5,000 cubic kilometres. Hollowed out, it would have space enough for the world’s reserves of coal and oil six times over.

The reader may have noticed that Furnival’s “100 times the annual volume of carbon dioxide emitted from all Europe's power stations” is a bit at variance with Williams’ “all of Europe's 600 billion tonnes of CO2 emissions for the next 600 years.” But we will let that pass.

Furnival goes on to say:

After several years of experimental study, a commercial plant was installed on the Sleipner platform in time for the start of production in 1996. Two MEA [monoethylamine] absorber columns were installed that reduce the CO2 content of the gas to 2.25%. Four compressors – standard items of equipment on most oil and gas platforms – are then used to pressurize the nearly pure excess carbon dioxide to 80 × 10^5 Pa, before it is injected into the base of the Utsira aquifer 1 km below. The high pressure is significant because carbon dioxide has a "critical point" at a temperature of 31 °C and a pressure of 74 × 10^5 Pa, beyond which it exists in a "supercritical fluid" state with a density of about 700 kg m^–3 [ie 700 kg/cubic metre]. Since injecting CO2 will raise the pressure in the aquifer, the CO2 remains in this fluid state.

Although much denser than a gas, the supercritical CO2 is less dense than water so it will start to migrate upwards. Understanding where and how this fluid moves is the main issue for ensuring long-term capture, and one that is being addressed by teams of geologists, geophysicists and reservoir engineers employed by oil companies to unravel the structure of underground reservoirs. [13]

Note that 10^5 Pa (ie 10^5 pascals) is a pressure of one atmosphere. So 80 x 10^5 Pa is a pressure of 80 atmospheres. For comparison, a car tyre commonly operates at a pressure of about 2 atmospheres.

Given Furnival’s quoted liquid CO2 density of 700 kg/cubic metre (ie 0.7 tonne/cubic metre), our hypothetical 5,000 cubic kilometre storage, conceived of for the moment as a ‘cave’, will hold around 3.5 x 10^12 tonnes of CO2.

The European Environment Agency’s latest report on GHG emissions is on the web [14]. According to that EEA report, the 15 countries of the European Union as in 2004 had total GHG emissions of 4,227.4 million tonnes, not all of it, of course, from thermal power stations. The subsequent admission of eight central and eastern European nations plus Cyprus and Malta has pushed the total to 4,979.5 million tonnes for that year. That is, 5.0 gigatonnes when rounded. As that would require only 1/700 of the space in the ‘cave’, it leaves a lot of room for supporting rock as well. The CO2 will actually reside in pores in the rock, and note that for this purpose I have assumed that all the GHG is CO2. It would take 700 years to fill the ‘cave’ with Europe’s emissions at their present rate, provided it was a hollowed-out chamber.

So what about Nikki Williams claim about storing “Europe's 600 billion tonnes of CO2 emissions for the next 600 years”? Well, 600 billion is 600,000,000,000, or 6.0 x 10^11 tonnes, and the empty ‘cave’ will hold 3.5 x 10^12 tonnes of CO2. The CO2 will take up 17% (nearly a fifth) of the room in it, which seems a lot of space for the interior of porous rock. Utsira has shown that it can take one million tonnes of CO2 produced in the adjacent oilfield in a year. However, this is dwarfed by the increase of emissions of greenhouse gases from the EU-25, which increase was by 18 million tonnes (0.4 %) between 2003 and 2004. Emissions from the EU-15 increased by 11.5 million tonnes (0.3 %) in the same period. [15] That is to say, the increase per year alone is eighteen times the mass of CO2 injected per year to date into the Utsira aquifer, which helpfully is in close proximity to the CO2 source: the Sleipner oilfield. Something like Utsira, although impressive in size, might be used for all of Norway’s future emissions, but not all of Europe’s. That would require a multitude of sequestration sites closer to the points of production.

More detail is available in the reports of The European Environment Agency [16] and [17]. Also [18].

Nikki Williams was not wrong, though she may have stretched it a bit. But her article calls forth not so much an argument over big numbers, as the reply: ‘should we bury carbon dioxide forever?’

For CCS to make a meaningful contribution to alleviating the CO2 problem, a number of conditions have to be met:

  1. The source of the CO2 has to be close enough to the burial site to make transport to it practical. Many sources require many short pipes to many sinks. Otherwise, a network of pipelines from many sources to a few sinks will be necessary. The longer the pipe network, the greater the potential risks, such as random leaks, and those deliberately brought about by vandals, saboteurs and terrorists. If such take place in densely populated areas the results can be disastrous, as CO2 gas is deadly in the quantities and transportation rates envisaged for CCS.
  2. The containment beds such as saline aquifers (eg Utsira) and disused oil and gas wells have to be gas tight.
  3. Some arrangement for dealing with future situations in which CO2 starts leaking out of the geological store has to be in place.
  4. Future drilling exploration and mining into layers underneath the CO2 store will become significantly more expensive and dangerous, or have to be foregone completely. The economic consequences of this, all other factors being constant, will be in proportion to the geological area covered by the CO2 store. This will likely be comparable to the geological area of the original coal and oil fields from which the carbon was taken. The horizontal dimensions of Utsira (500 km by 50 km, and just one of many fields) give some idea of it.
  5. The mass of liquid CO2 to be stored if the program is to be successful is huge: in the order of 3 times the total mass of coal in the world’s coal reserves (which as we have seen is 909 Gt). That is, if we assume that acidification of the ocean by CO2 has reached saturation level and crisis point in terms of its effects on corals and other basic life forms, and that the ocean literally cannot take it any more. That in turn means 3 x 909 Gt or 2,727 Gt of carbon dioxide have to be captured and stored in order to protect the ocean. That is, 2.727 x 10^12 tonnes.
  6. Then there is what I call the seismic hydraulic jack problem, of which more below.

Protecting the atmosphere would be about 100 times easier than protecting the ocean, if that was all we had to do. The mass of the Earth’s atmosphere is 5.14×10^18 kg, and the total mass of atmospheric carbon dioxide is 3.0×10^15 kg, or 3,000 Gt. [18.5] The concentration of CO2 in the atmosphere is increasing by 0.4% per year, because the natural sequestering systems cannot cope with the Earth's total annual increase in CO2 production. So the amount that must be sequestered per year by other than natural means, just to hold the global atmospheric concentration constant, is 0.4% of 3,000 Gt or 1.2 x 10^10 tonnes, globally. When we write that out in longhand, it comes to 12,000,000,000 tonnes per year, or 33 million tonnes of CO2 per day.

Australia’s share of the task is no trifle either. In 2004-5 Australian total domestic energy consumption was 5,525 petajoules (PJ). [19.5] Of this, 41 % came from coal, 35% from oil, 19% from natural gas and 5% from renewables. 41% of 5,525 PJ is 2,265 PJ, which translates to 79 million tonnes of coal. If we assume this to be on average 70% carbon, that makes 55 million tones of coal, which burned to yield around 200 million tonnes of CO2 that year; around 560,000 tonnes per day: the mass that must be buried under Australia if locally-burnt coal is to contribute zero CO2 to the global atmosphere and ocean problems.

These are huge capture and storage problems in themselves. However, there are also problems with the whole feasibility of CCS, even if on an industrial scale it can handle the daily mass of CO2 involved. Note that CCS only has relevance at present to coal, which these days is generally burnt in a relatively few huge furnaces in such establishments as power stations and iron smelters. However, we have seen that the remaining coal reserves contain 79% of the fossil fuel carbon, the oil reserves 11%, and the natural gas reserves 10%. The world thus has around eight times as much coal reserves as it has of petroleum reserves, and four times as much in the coal as in oil and natural gas combined. Carbon capture and storage is not applicable to most domestic and industrial uses of gas and petroleum fuel, so the future of captured carbon is largely the future of CO2 derived from the burning of coal. Such future devices as ‘plug in and charge’ automobiles, will run in on energy from coal unless renewables take its place.

Steve Furnival:

Once a suitable site has been chosen, the mechanics of storing carbon dioxide are not too difficult – it just involves a few pipes, some injection wells and equipment to compress the carbon dioxide before it is stored. The main issue is to ensure that once injected, the carbon dioxide will not find its way back to the surface in any significant amounts. The most likely leak path is through wells, both active and abandoned. Furthermore, when water and carbon dioxide mix they form carbonic acid, so new sealing methods must be developed using cements that are resistant to this chemical attack. Long-term monitoring for leaks will be needed too – a responsibility that must be borne by governments since no commercial organization would take on such an open-ended commitment. While the lifespan of a typical oilfield is between 20 and 50 years, monitoring of CO2 leaks may be needed for millennia.

Here indeed is a major snag in the fine print of the contract. Potentially, it is the most outstanding example in all of economic history of what John Kenneth Galbraith called ‘privatised profits and socialised losses.’ Once Australia’s or any other country’s government allows its private CO2 emitters to start moving down the CCS path, it must accept total liability, literally from here to eternity, for anything which might go wrong. That includes the foreseeable, like leaks, and the unforeseeable, like literally God knows what. It would be a very brave actuary, working for an insurance company with very deep pockets and most charitable shareholders, who would even try to work out the statistics on that, let alone suggest an annual premium for that total liability.

So I have serious reservations about the whole business, and regard the $500 million earmarked in the last Australian budget for CCS as likely to be wasted. Although it will all finish up in certain peoples' bank accounts, whether it will do any good as it makes its way into them is an open question.

Steve Furnival:

The main disincentive to wide-scale adoption of CCS is the expense. It is estimated that CCS will cost between [US] $25 and $50 per tonne of CO2, of which 80% is the cost of capture. To get a feel for this, consider that each tonne of coal burned produces about three tonnes of CO2, and that a typical 1 GW coal-fired power station produces 6 million tonnes of CO2 per year. The energy required to operate an effective capture scheme at a power plant would therefore significantly reduce its operating efficiency. Although it should be possible to reduce the cost of CCS by 20–30% in the next decade, further savings will depend on the adoption of the technology together with on-going research and development. In the mean time, a tax on carbon-dioxide emissions would certainly make CCS more economically attractive…

A major concern when storing carbon dioxide in saline aquifers is that the natural seal at the top of the formation – a layer of non-porous rock – could be broken during CO2 injection. So far, this seal has remained intact at Utsira, but if it does eventually break, the hope is that a series of shallower seals will minimize the amount of carbon dioxide that will escape…

The probability of such escapes happening is likely to be a function of the mass of CO2 stored, the time stored, and the number of seismic movements per year, as measured over millenia.

Furthermore, it is believed that over a period of about 1000 years carbon dioxide will dissolve in the brine inside the aquifer, producing a CO2–brine mixture that is heavier than unsaturated brine. The saturated brine will thus move downwards, helping to lock the carbon dioxide away. Longer term still, on geological timescales, it is believed that chemical reactions will turn the CO2–brine mixture into a mineral, locking the carbon dioxide permanently into the Earth's crust.

Reading through the above, we can see that there is far more faith and hope amongst CCS advocates than there is scientific certainty, which is understandable, as there is no such thing as absolute certainty in science. The dark horse in the race is seismic movement, and particularly the possible contribution of the massive and geologically extensive high-pressure liquid CO2 storage in the sedimentary layers below the Earth’s surface to the very same seismic movements that might give rise to such release. What the geosequestration wells will set up will be in reality an array of gigantic hydraulic jacks. The force exerted upwards on the overlying strata by the gigatonnes of sequestered liquid CO2 will be equal to about a third of the weight of the overlying strata. As we have seen, the CO2 will require a pressure in the order of 100 atmospheres to remain liquid in the temperature conditions found at a sequestration depth commonly around 1 kilometre below the surface. Deep wells are favoured because of the containment strength needed. But even in the deepest, the gas pressure could have a significant easing effect on the friction blocking relative movement of adjacent strata. Applied over the areas envisaged, this could be of seismic significance. Literally.

Admittedly, the gigantic ‘slave cylinders’ [19.55] of the jacks (ie the sequestration reservoirs below ground) will not have impervious walls, as those of normal hydraulic jacks do. The pressure in the liquid CO2 below will even out as water is displaced through the porous reservoir rock. A moment’s reflection shows that if the reservoirs were watertight, liquid CO2 could not be pumped into them in the first place, as liquids are incompressible. But of course, this raises the next question: where will this displaced CO2-plus-water mix finally end up? If it moves downward or horizontally, it could eventually find its way via a submarine outcrop of the aquifer into the ocean, and from there the CO2 component could return to the atmosphere. This may not necessarily be bad for the biosphere or humanity, provided it happened slowly enough.

Apart from the six problems with CCS listed above, there is a seventh, and far more major one. It may appear to be a long term problem, and therefore dismissible by politicians and others who only permit themselves to think in the short term. But it will phase itself in as the existing carbon economy is phased down and then out over the anticipated life of the present deposits of fossil carbon fuel.

      7. Humanity cannot afford to bury the CO2 forever, because our descendants in the period of human historical time beyond the lifespan of the present fossil fuels (50 years for petroleum, perhaps 250 years for coal) will need the carbon. With high probability.

250 years backwards in time takes us from 2008 to 1758: that is to the period around the start of the Industrial Revolution in Britain, when the Enlightenment foundations of much that distinguishes modern thinking from what preceded it were being laid, and the CO2 concentration of the atmosphere was just starting on its exponential trend upwards. Nineteen years on from 1758, James Cook would step ashore at Botany Bay. So it is not so far further on from this present point in human history before a decision today to close off the options of later generations could well be seen as one of the stupidest choices members of our species have ever made.

We should not “bury carbon dioxide forever”. It should only be buried, if at all, for as long as it takes to restore pre-1758 atmospheric CO2 concentrations, and should always be retrievable. The problem affecting the present atmosphere and ocean is the unprecedented rate at which CO2 is being added to them both.

We have unwittingly been running an experiment on the planet, and with only limited control of variables. With luck, it will yield data sufficient for future scientists to make reasonably confident predictions as to the effect of particular atmospheric CO2 concentrations on the global climate. We are, with Kyoto, embarking on our second attempt to actually control the climate of the whole world, by controlling the concentration of GHG. The first was the (moderately successful) attempt to patch the hole in the Ozone Layer by progressively banning chlorinated fluorocarbons from mass usage in refrigeration and other applications. At the Montreal Summit, on September 21, 2007, approximately 200 countries agreed to accelerate the elimination of hydrochlorofluorocarbons entirely by 2020. Developing nations were given until 2030. Many nations, such as the United States and China, which had previously resisted such efforts, agreed with the accelerated phase-out schedule. [19.555]

By holding all other factors constant in controlled environment experiments, plant physiologists have repeatedly shown that the carbon dioxide concentration in the air available to the plant is the major limiting factor on plant growth. Number [20] in the links and references list below is a report of but one typical experiment. It is likely that the plants of the biosphere will increase their rates of photosynthesis and growth as the concentration of atmospheric CO2 rises, provided global warming does not produce factors like drought and heat stress which drive them in the opposite direction. Eventually as fossil fuel reserves run down, and provided we do not pass a tipping point along the way and enter runaway greenhouse conditions, the CO2 will stop its rise in atmospheric concentration, peak, and then start trending downwards, as photosynthesis exceeds combustion and respiration combined. Other factors could well join in along that way to plunge the planet into a new ice age. The ability of the human population of the globe at that time to elect to stay out of such a development will likely depend on its having the ability to adjust the atmospheric CO2 concentration to suit itself. In those circumstances, a decision on the part of this generation to “bury carbon dioxide forever” and seal the captured carbon storage wells permanently after filling, would be seen as careless and short-sighted. So carbon geosequestration should always be carried out in such a way as to not cut off the option to retrieve the CO2 at a later date. The extent to which that can actually be done remains to be seen.

In 2000, the Dutch atmospheric chemist and Nobel prizewinner Paul Crutzen [21] coined the term Anthropocene for the period of geological time we are now living in. It appears to be catching on in the scientific community. [22] [23] The preceding Holocene period began 10,000 years ago when the Pleistocene glaciers had retreated sufficiently to allow agriculture to begin. Argument now occurs as to when, if at all, it ended and the Anthropocene began. Crutzen says:

To assign a more specific date to the onset of the 'Anthropocene’ seems somewhat arbitrary, but we propose the latter part of the 18th century, although we are aware that alternative proposals can be made (some may even want to include the entire Holocene). However, we choose this date because, during the past two centuries, the global effects of human activities have become clearly noticeable. This is the period when data retrieved from glacial ice cores show the beginning of a growth in the atmospheric concentrations of several 'greenhouse gases’, in particular C02 and CH4. Such a starting date also coincides with James Watt's invention of the steam engine in 1784. [24]

I like the term, but would argue that the period began very abruptly: on September 21, 2007, when the Montreal Protocol was signed, marking humanity’s first conscious step towards climate control of the whole planet. The Kyoto Protocol, which was adopted on 11 December 1997 and entered into force on 16 February 2005 was a second, and far more difficult advance. [25]

Carbon is presently being moved out of one of its major stores on our planet, the rocks, and into another, the atmosphere. Human civilization presently depends as heavily on the carbon stored in the lithosphere as it depends on what is in the biosphere. The plants are hardly benefiting from this transfer, particularly as the Earth warms as a result. Today it is no exaggeration to say that we are not only transported about the face of the Earth by petroleum and coal, we also eat it, drink it, wear it and shelter under it. (For example, roofing iron is galvanized steel, smelted from its ore using coal.) We will be able to continue in our present style of carbon dependence if, and only if, the lithosphere carbon is moved slowly and steadily into the biosphere. Otherwise, when the fossil fuels finally run out, the biosphere, operating on roughly its present carbon mass (plus what it gets from the CO2 from the burning of fossil fuels other than coal, which cannot be geosequestered) will have to carry the full load. Its carbon will have to supply all our carbon-based needs.

The geosequestrationist proposal is to bury the CO2 forever back into the rock of the lithosphere. The case I have been setting out in this document is that the greatest benefit would arguably come about if we gradually returned the planet to the pre-Carboniferous situation, before its largest ever carbon store transfer, which was from the biosphere to the lithosphere. A progressive transfer of the carbon coming out of the lithosphere back into the biosphere would involve, and in no small measure, the reafforestation of the globe. It was much more extensively forested in the Carboniferous and the Permian.

The plants will do that by themselves if we give them the time (say a few hundred years) and a bit of conscious assistance. Ecological successions of them could take back the Sahara, the Great Sandy, the Gobi, and most of the other deserts of the world.

The US Census Bureau has estimated that the world’s human population will be 9.4 billion by 2050. [26] It is 6.7 billion today. [27] By that time also, says the prevailing scientific consensus, GHG production will have to have been reduced to 50% or less of the 2000 level, and the atmosphere’s CO2 concentration stabilized. That is, if runaway global warming is to be avoided.

A CSIRO study published on July 11, 2008 predicts that by 2018, petrol in Australia will cost around $8.00 per litre. (The previous day, the CSIRO announced success in capturing CO2 in flue gases at Loy Yang Power Station, Victoria, with the experimental plant being capable of capturing 1,000 tonnes of CO2 per year, which is 2.7 tonnes per day. (!)) Thus as petroleum recedes over the next 40 years, crop plants of various kinds will be called upon increasingly to provide not just our food and fibre, but liquid fuels for transportation. Those 9.4 billion people of the year 2050 will need cotton for their clothes, wood for their housing, cooking and home heating, fodder for their livestock and crops of edible plants for themselves. They will also need fuels (most likely also derived from plants) not just for transport, but for a host of industrial purposes as well.

I do not think that it is a wise move to pump the CO2 that could feed all those future plants, and those dependent on them, irretrievably, permanently and forever into the depths of the Earth. Thus the inescapable conclusion is that any carbon capture and storage scheme of a magnitude sufficient to have a noticeable effect on global climate has to be done in a temporary, retrievable way. Cutbacks in global production of CO2 from the burning of coal will have to make up for any shortfalls in CCS, which on the face of it, promise to be significant. That in turn means cutbacks in the production of steel, electricity and cement where these use coal as fuel.

And that in turn will mean significant, if not huge, price increases for those commodities. The only alternative would be to let the Earth fry.

If carbon capture and storage is capable of any significant dampening effect on global warming, then the CO2 involved will inevitably be a resource of massive importance for the future inhabitants of the Earth. That in short, is the other side of the CO2 coin. Our present climate change situation compels us to perceive atmospheric CO2 only as a problem. We should be seeing it differently: as a short term problem, but despite that, as a longer term vital resource.


[0.5] http://www.thehistorychannel.co.uk/site/encyclopedia/article_show/Parthenon/m0012197.html

[0.55] http://www.newadvent.org/cathen/01303a.htm

[0.555] http://en.wikipedia.org/wiki/Thylacine

[0.5555] http://www.greenpeace.org.au/blog/energy/?p=178

[1] http://www.garnautreview.org.au/CA25734E0016A131/pages/reports-and-papers

[1.1] http://en.wikipedia.org/wiki/Greenhouse_effect

[2] http://www.caer.uky.edu/iea/ieacr61.shtml

[3] http://en.wikipedia.org/wiki/Earth's_atmosphere

[4] http://www.uni-muenster.de/GeoPalaeontologie/Palaeo/Palbot/seite1.html

[5] http://en.wikipedia.org/wiki/Ocean (The total mass of the hydrosphere is about 1.4 × 1021 kilograms, which is about 0.023% of the Earth's total mass. Less than 2% is freshwater; the rest is saltwater, mostly in the ocean.)

[5.25] Hoffman, PF and Schrag, DP, Snowball Earth, Scientific American, January 2000. http://www.amherst.edu/~jwhagadorn/courses/27paleo/readings/HoffmanSchrag2000.pdf

[5.5] http://en.wikipedia.org/wiki/Chert#Chert_and_Precambrian_fossils


[7] http://en.wikipedia.org/wiki/Atmosphere_of_Venus

[8] http://en.wikipedia.org/wiki/Atmosphere_of_Mars

[9] http://en.wikipedia.org/wiki/Atmosphere_of_Titan#Atmosphere

[10] John C. Walton, The Chemical Composition of the Earth’s Original Atmosphere. http://www.grisda.org/origins/03066.htm

[11] http://www.ucmp.berkeley.edu/help/timeform.html

[11.5] http://www.ldeo.columbia.edu/edu/dees/V1003/lectures/global_carbon_cycle/

[12] http://www.theaustralian.news.com.au/story/0,25197,23508727-21147,00.html

[13] http://physicsworld.com/cws/article/print/25727

[14] http://reports.eea.europa.eu/technical_report_2007_7/en

[15] http://www.eea.europa.eu/pressroom/newsreleases/GHG2006-en

[16] http://reports.eea.europa.eu/technical_report_2007_7/en

[17] http://www.eea.europa.eu/pressroom/newsreleases/GHG2006-en

[18] http://www.climnet.org/resources/annex1emissions.htm

[18.5] http://en.wikipedia.org/wiki/Earth's_atmosphere#Density_and_mass

[19] http://en.wikipedia.org/wiki/Hydrofluorocarbons


[19.55] http://www.aphyedu.org/uploaddocuments/Nepad_Pressure1.pdf

[19.555] http://en.wikipedia.org/wiki/Hydrofluorocarbons

[20] http://adsabs.harvard.edu/abs/2002AGUSM.B22C..05J

[21] http://en.wikipedia.org/wiki/Paul_Crutzen

[22] http://en.wikipedia.org/wiki/Anthropocene


[24] http://www.mpch-mainz.mpg.de/~air/anthropocene/Text.html

[25] http://unfccc.int/kyoto_protocol/items/2830.php

[26] http://en.wikipedia.org/wiki/World_population#Forecast_of_world_population

[27] http://www.census.gov/main/www/popclock.html


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Who is going to pay for CCS? Can we afford it?

Measured against the sequestration capabilities of the world's three existing showcase projects, America alone would need 1,500 such plants to store the emissions generated by its electricity industry. Yet its one serious attempt to make CCS operational, in the form of the FutureGen project, was cancelled this year owing to an unexpected hike in costs from $830 million to $1.8 billion. And although the European Commission has called for upwards of a dozen commercial coal plants with CCS to be deployed by 2015, how they will be funded is anyone's guess.

At this rate of progress, the goal of broad deployment of CCS on coal plants by 2020 is a vain hope — and with new plants being deployed by the dozen, CCS can't come quickly enough.

CCS is going to be extremely expensive and more than likely the world will not have the skills or the time to implement CCS on existing coal fired power stations. We must realise that coal will not be in the mix if we are to reduce global emissions in time to save the planet from catastrophic climate change.

The potential of solar power is vitually unlimited.

Considering that the energy in sunlight reaching the earth in just 70 minutes is equivalent to annual global energy consumption, the potential for solar power is virtually unlimited. With concentrating solar thermal power (CSP) capacity expected to double every 16 months over the next five years, worldwide installed CSP capacity will reach 6,400 megawatts in 2012 -- 14 times the current capacity.

Unlike solar photovoltaics (PVs), which use semiconductors to convert sunlight directly into electricity, CSP plants generate electricity using heat. Much like a magnifying glass, reflectors focus sunlight onto a fluid-filled vessel. The heat absorbed by the fluid is used to generate steam that drives a turbine to produce electricity. Power generation after sunset is possible by storing excess heat in large, insulated tanks filled with molten salt. Since CSP plants require high levels of direct solar radiation to operate efficiently, deserts make ideal locations. />

Two big advantages of CSP over conventional power plants are that the electricity generation is clean and carbon-free and, since the sun is the energy source, there are no fuel costs. Energy storage in the form of heat is also significantly cheaper than battery storage of electricity, providing CSP with an economical means to overcome intermittency and deliver dispatchable power.

Concentrating solar thermal power is expected to double every 16 months with its capacity to provide clean base load 24 hour energy. Why isn't Australia with an abundance of desert sunshine leading the charge instead of wasting billions on trying to capture C02 from obsolete coal power stations?

We need to be building these power stations now and closing down the coal power stations.

The jobs lost in the coal industry will be replaced by jobs in the new solar power industry.

The end is nigh.

An interesting interview of Chris Nelder author of Profit from the peak.

The failure of governments  to see the urgency of switching to alternate energy is going to cost us dearly. 

I feel like a man standing on a corner with the sign "The End is Nigh" but no one is listening.

Coal is here to stay. Catastrophic climate change is inevitable

Mr Ferguson says coal is here to stay, and a long-term strategy is needed to nurse the resource industry through climate change transitions.

"Australia is a nation that is highly dependent on coal for electricity," he said.

"The Government is confident that, working both domestically and internationally, in partnerships with state governments and also the business sector, we will make progress on the development of low emissions coal."

NASA scientist Jame Hansen says we must phase out coal.

“Building new coal-fired power plants is ill conceived,” said James E. Hansen, a leading climatologist at the NASA Goddard Institute for Space Studies. “Given our knowledge about what needs to be done to stabilize climate, this plan is like barging into a war without having a plan for how it should be conducted, even though information is available.

“We need a moratorium on coal now,” he added, “with phase-out of existing plants over the next two decades.”............

In fact, the technology that the industry is counting on to reduce the carbon dioxide emissions that add to global warning — carbon capture and storage — is not now commercially available. No one knows if it is feasible on a large, cost-effective scale.............

The task — in which carbon emissions are pumped into underground reservoirs rather than released — is challenging for any fuel source, but particularly so for coal, which produces more carbon dioxide than oil or natural gas.

Under optimal current conditions, coal produces more than twice as much carbon dioxide per unit of electricity as natural gas, the second most common fuel used for electricity generation, according to the Electric Power Research Institute. In the developing world, where even new coal plants use lower grade coal and less efficient machinery, the equation is even worse.

Without carbon capture and storage, coal cannot be green. But solving that problem will take global coordination and billions of dollars in investment, which no one country or company seems inclined to spend, said Jeffrey D. Sachs, director of the Earth Institute at Columbia University.

“Figuring out carbon capture is really critical — it may not work in the end — and if it is not viable, the situation, with respect to climate change, is far more dire,” Mr. Sachs said.

Mr Ferguson says "coal is here to stay". At best clean coal technology is ten to twenty years away. If we want to replace existing coal fired power stations world wide "clean coal" will not be an affordable option. Many believe that the technology may not work at all.

Can we afford to waste money on a technology that will not be available soon enough to prevent catastrophic climate change? Should we risk the future of the planet or should we be investing in clean energies that are currently available?

It is time for the Rudd government to get serious on reducing our emissions.

Calling Ian MacDougall, John Pratt

In respect of what passed before, on the production of CO2, perhaps you can enlighten me further.

So CO2 is produced by carbon uniting with oxygen. I can see the sense in that proposition. But on reflection I have a bit of a problem with it, as follows.

When we ferment malt to make beer, we aerate our diluted malt before adding yeast, because yeast cells needs oxygen to grow and proliferate. Conventional wisdom has it that all the oxygen, which is an enemy of beer and must be eliminated from it in order for the beer to be good, is all used up and absent within about an hour of the commencement of fermentation. The yeast has used it all up, and now the nascent beer must not be allowed to come in contact with air.

Yet the yeast continues to produce CO2 for many days after the dissolved oxygen is all gone. The yeast continues its work in the absence of oxygen. And in its work, it continues to produce enormous volumes of CO2. Were it not vented, the fermenting vessel would explode. My question is, since this production of CO2 cannot be due to a combining of carbon and oxygen, where does it come from?

Respiration and fermentation

Bill, yeast cells normally respire like most other cells do, oxidising sugar to CO2 and water, and extracting energy in the process. But in the absence of oxygen they can carry out the following reaction:

Chemical equation

C6H12O6 → 2 CH3CH2OH + 2 CO2 + 2 ATP (energy released:118 kJ/mol)

Word equation

Sugar (glucose or fructose) → alcohol (ethanol) + carbon dioxide + energy (ATP)

As you will be able to see from the above, the atoms in the CO2 molecules produced in fermentation (they are on the right hand side of the equation) come from the breakup of the sugar molecules on the left hand side of the equation. In the reaction, I should add, the ATP (adenosine triphosphate) shown as a product, picks up energy only from the sugar to alcohol + CO2 reaction. The energy of the reaction drives a parallel ADP (adenosine diphosphate) to ATP reaction. ATP is a molecule used in biochemical systems as a general energy carrier.

Because fermentation involves incomplete oxidation, the alcohol produced can be oxidised further. Hence the use of alcohol as a fuel.

$1.5 billion to be spent on clean coal fund

Resources and Energy Minister Martin Ferguson has announced it will do this by using its $500 million clean coal fund to form the National Low Emissions Coal Council and the Carbon Storage Taskforce.

Industry and state governments will contribute a further $1 billion.

"As we all appreciate, coal is Australia's largest export and is the primary fuel for about 80 per cent of Australia's current power supply," Mr Ferguson said.

"Clearly no serious response to climate change can ignore the need to reduce emissions from coal."

"The fact remains that significant emission reduction must flow from our coal-fired power stations - it is a fact of life."

The government should not be picking winners in an effort to reduce our GHG emissions. If coal cannot be made to produce clean energy this will be a huge waste of money.

During the 1980s, Congress ponied up $2.75 billion for the Department of Energy's Clean Coal Technology program, which sponsored 31 demonstration projects. The cleanest projects, called "combined-cycle coal-gasification plants," turn coal into gas, which is burned to generate electricity.

So far, there have been no commercial orders for them. In recent years, utilities have almost exclusively built natural-gas-fired plants, which meet environmental standards and use a fuel that -- until last year -- was abundant and cheap. In fact, $467 million of the demonstration money remains unspent.

Already billions have been spent with no success.

Last year, plans for more than 50 conventional coal-fired plants were canceled or delayed due to concerns about the environmental impact or through fear that carbon legislation is coming that could make their output uneconomic. The federal government has repeatedly held out the promise that technologies would be developed to clean up coal.

"People don't understand the magnitude of the problem," said Howard Herzog, principal research engineer for M.I.T.'s Carbon Capture and Sequestration Program. "How can we do hundreds of these plants by 2050 -- and that's what we'll need -- if we can't even do one?"

If progress on clean-coal technology isn't made soon, AEP's Mr. Morris said, "we'll have to move nuclear up the ladder." Indeed, the nuclear-power industry is already experiencing an unlikely rebirth in part because it is seen as a cleaner alternative to other electricity sources.

Renewable energy sources

It is vital that the remaining fossil fuels are used to develop renewable energy sources.  Unfortunately these fossil fuels  will be more expensive, as they require more energy to recover (in the case of oil) and more energy to mitigate the carbon dioxide emissions.  Creating wind turbines and solar panels without fossil fuel input will be very difficult.

As an aside, in chemistry nothing is for free.  To separate carbon dioxide from exhaust gases at power stations, transport it and pump it as a supercritical fluid into aquifers will require energy.  This will reduce the efficiency of the power station.  Eventually, the entire value of the energy produced from coal may be required to dispose of the carbon dioxide!  In the same way, some oil sands in Canada require more fossil fuel to extract it than the sands contain

Peak oil the end of economic growth.

Peak Oil does not mean that civilization is about to run out of oil. Instead, we are near (or at) the point where continued growth of petroleum combustion no longer can be maintained, which will have profound consequences for the global economy that is dependent on exponential growth of nearly everything (especially of money supplies). Energy creates the economy, a physical limitation rarely acknowledged by economists. Peak Oil is also the point where the maximum amount of economic "growth" is reached -- and ideally a turning point where we can decide to use the remaining half of the oil as a bridge toward a more sustainable way of living. It would require enormous energy, money and people power to reorient away from NAFTA Superhighways toward investing in bullet trains, away from dirty fossil fuel technologies toward efficiency and renewable energy systems, away from resource wars and toward global cooperative efforts to reduce our collective impact on the planetary biosphere.

The world's economic growth currently depends on energy created by the burning of fossilized carbon which combines with oxygen in the atmosphere to create C02. This is the energy wealth that has created our global capital. The atmosphere and oceans are being polluted by C02 which is creating enormous problems for our children and their children. We must use the remaining half of the oil as a way to bring about a sustainable way of life.

We must learn from the capitalists and not waste all our capital.

Ocean acidification, marching toward disaster.

While the existence of global warming was fiercely debated for decades, ocean acidification has been rapidly accepted by the scientific community as a real and imminent hazard. “It is very complicated to pin the heating of the planet on a single gas, but ocean acidification involves straightforward chemistry,” says Robert B. Dunbar, professor of geological and environmental sciences at Stanford University. Since it is easy to chart the step-by-step progression of the problem, there is widespread consensus that we are marching toward disaster at a pace that is impossible to ignore.

A few of us still think the link between carbon and global warming is hard to prove, but the link between ocean acidification and carbon is pure chemistry. Another very good reason for reducing our C02 emissions is the fact that we our putting the world's supply of food from the ocean at risk.

The other problem with carbon capture and storage.

But the biggest argument of all for caution — yet hardly ever spoken — is that there simply may not be enough coal to go around. This could lead to global shortages, price spikes, economic disruption and a rush to other energy sources — meaning billions of dollars of stranded investments.

Incredibly for an energy resource that the world depends on, global coal statistics are shockingly poor. Take China. Since 1992, the nation has mined roughly 20% of its reported reserves. Yet, China hasn't changed its reported reserve figures since that year. The United States and Australia have reasonably credible reserves, but other nations with large reported coal assets are Russia, India and South Africa. How reliable are their figures?

Put bluntly, neither the world nor Australia should commit to carbon capture and storage until there is a better global accounting of the underlying energy resource.

Not much point investing in carbon capture and storage if there is not enough coal to meet demand. Yet another reason why we must use alternative energy to produce electricity. We may have no other choice. Even if we ignored climate change we will still need alternative energy. Why not make the move sooner rather than later?

Where is the carbon?

Handy table from Garnaut (p64). You can see why some people are a tad worried about the deep ocean reversing cycle at higher temperatures ... 

carbon sinks

Day Of The Triffids

Bill: "...we'd have to have a perpetually increasing number of plants in the world just to keep things stable."

We're not manufacturing more carbon worldwide as far as I know, so I suspect we wouldn't have to perpetually increase the number of living plants. But we would have to raise the number to a level compatible with the greenhouse-sustainable rate of carbon release from

  1. our fossil fuel burning activities, in addition to:
  2. the natural release rate (thanks for the ecology lessons everybody!).

Of course as the former decreases due to increasing scarcity, the actual number would be reduced. Then again, giving the metric buttload of carbon given off in the last few centuries compared with the millions of years of buildup locked into the oil/coal/gas reserves, it might feel perpetual to our descendants...

The damage has already been done

Chris, I don't suppose we are manufacturing carbon, but we are in various ways releasing carbon dioxide into the atmosphere. Fossil fuels, especially coal, don't look like running out for a while yet. If we were able to stabilise our CO2 emissions at current levels, we would still be emitting plenty, and what we emit would be adding to the too much that is already there.

It therefore seems to me to follow that we would need ever-increasing numbers of plants to absorb the ever-increasing amount of CO2 in the atmosphere. And that means semi-permanent plants like trees, because crop plants release their stored CO2 as soon as they are processed or consumed. As we speak, trees are being cleared from the land to make it available for crop plants.

Further to that, the global warming caused by greenhouse gasses causes more greenhouse gas to be produced. For one thing, the oceans, as they warm, will release the CO2 naturally absorbed by the water when it was cold.

900 megatonnes of carbon sequestered per annum in pasture.

Professor Peter Grace of the Queensland University of Technology is an expert on agriculture and greenhouse emissions and estimates that in an ideal situation, more than 900 megatonnes of carbon dioxide equivalents could be sequestered per annum through improved pasture management.

"It's a very significant amount of carbon," he said.

Professor Grace says even if only 10 per cent of this amount was achieved it would result in a significant reduction in Australia's carbon emissions.

Despite this, most experts, including the Garnaut draft report, say agriculture can only be included in a national emissions trading scheme when there is more rigorous scientific data available on what is emitted and sequestered.

Professor Grace says one way to sequester carbon is to grow a bigger crop using more fertilisers.

Ian, more on agriculture and carbon sequestration. If we practiced better farming techniques we might be taking out more C02 than we are putting into the atmosphere from the use of fossil fuels. It looks like we should be doing a lot more agricultural research into the possibilities. The ABC did a story on this on their Bush Telegraph program this morning.

Plant sequestration

John, thanks for the comment and the link to the Carbon Coalition Against GW site. Most interesting.

I wonder if the C02 pipelines need to connected to C02 storage sites.

Surely it doesn't matter where we take the C02 out of the atmosphere as long as we do it.

Couldn't we store C02 in the soil, by rewarding farmers to contribute to carbon sequestration?

There is only one sure-fire method for taking CO2 out of the air once it is in, and that is to let the green plants and other CO2-utilising organisms do it. Their decay in turn builds up the permanent store in the soil and sites like peat bogs, some of which are huge. Though various schemes are floated from time to time for 'decontaminating the air' using industrial-scale scrubbing plants, the mass of CO2 in the atmosphere is so huge that any such scheme is likely to be folly, if not a deliberate con by some vested interest or other.

CCS as presently proposed only applies to the coal industry. As far as I can see, the intention is to rapidly develop the technology, and then pass it on to coal cutomers (probably give it away with each coal export deal signed), so that Australian coal burnt anywhere in the world need not contribute to the global warming problem. That would literally make it 'clean coal'.

Time was when every house in Sydney just about burned coal in the winter in one or more fireplaces. These days domestic heating is via natural gas or electricity (which means coal burnt in a power station). Heating oil is on its way out. CCS would apply to gas-fired power stations, but not to domestic heaters, car exhausts or other small-scal CO2 shortages. Australia's ability to continue increasing its coal exports after Kyoto is seen as hanging on CCS.

The masses of CO2 to sequester per day are so huge that pipeline transport is seen as the only practical way. A tonne of coal when burnt produces about 3 tonnes of CO2, so compressing the gas and moving it by sea, rail or road would be at least 3 times as expensive as moving the coal that produced it.

I personally doubt that there is time to get the capture technology going, scale it up, find the sequestration sites (as close as possible to the CO2 sources) and build the infrastructure before the CO2 load in the air reaches tipping point for runaway greenhouse. If CCS proves too slow and less than adequate, CO2 production from coal and all other sources will have to be cut back. That means steel, electricity, cement, aluminium, transport and everything else, and in a big way. So yes, a massive effort to expand and protect the areas of the Earth covered by plants might turn out to be not just the best, but the only  way to go to get CO2 safely down out of the air.

A ton of feathers, or a ton of lead?

Ian MacDougall:  "A tonne of coal when burnt produces about 3 tonnes of CO2".

So you take a lump of carbon, set it alight, and not only get to use its heat, and end up with a pile of ash and a cloud of smoke, but you end up with three times the mass of carbon you started with?

If you or anyone can explain how that makes sense, I'd be grateful. Makes Jesus' trick with the loaves and fishes look tame by comparison.

The carbon in the coal combines with the oxygen in the air.

Bill, hope this helps:

The carbon dioxide emission factors in this article are expressed in terms of the energy content of coal as pounds of carbon dioxide per million Btu. Carbon dioxide (CO2) forms during coal combustion when one atom of carbon (C) unites with two atoms of oxygen (O) from the air. Because the atomic weight of carbon is 12 and that of oxygen is 16, the atomic weight of carbon dioxide is 44. Based on that ratio, and assuming complete combustion, 1 pound of carbon combines with 2.667 pounds of oxygen to produce 3.667 pounds of carbon dioxide. For example, coal with a carbon content of 78 percent and a heating value of 14,000 Btu per pound emits about 204.3 pounds of carbon dioxide per million Btu when completely burned.(5) Complete combustion of 1 short ton (2,000 pounds) of this coal will generate about 5,720 pounds (2.86 short tons) of carbon dioxide.

The carbon in the coal unites with the oxygen in the atmosphere 1 part carbon to 2 parts oxygen C02 during the burning process. The extra mass comes from the oxygen taken from the atmosphere and converted into carbon dioxide. So 1 ton of coal makes 2.86 tons of C02.

Thanks Ian and John

Now I see. I should have been able to figure that out for myself. I knew that CO2 meant a combination of two molecules of oxygen and one of carbon.

Now I'm even more depressed. Not only are we filling the air with CO2; we're depleting our oxygen supply in the process… no wonder I'm feeling breathless.

Everyone (except Michael Moore, who found it hard to believe, but he was educated in America) knows that plants absorb CO2 and release oxygen. That's good, except that when they die they stop making oxygen and release all the CO2 they've ever absorbed back into the air, right? I hope I'm not right, because if I am that would mean we'd have to have a perpetually increasing number of plants in the world just to keep things stable. And that is not likely to happen.

I almost perpetually dismantle grain carbohydrates with the help of yeasties, in order to make alcohol. In the process, I must be guilty of producing enormous amounts of CO2. One teaspoon full of sugar, when it is fermented, makes less than a millilitre of ethanol, and about 2.5 beer bottles full of CO2. I have no idea how to estimate its weight. I know where to weigh a whale, ( a whale-weigh station) and where to weigh a pie (somewhere over the rainbow), but weighing a gas is beyond me.

I can live with not knowing how to weigh everything; but what I would like to know is, if we're going to power our machines with ethanol, how is that going to reduce CO2 emissions? Do the big producers of fuel ethanol contain the CO2 they produce? And if so, what do they do with it?

The Secret Life Of Plants

Bill: "when they die they stop making oxygen and release all the CO2 they've ever absorbed back into the air, right?"

While alive, the plants breathe in CO2 and break it up. The oxygen gets exhaled for us to breathe, while the carbon goes into making wood. So when the plant dies, the carbon is locked up until we burn the wood (or until the plant becomes oil which some descendant of ours in a few million years may decide to burn).


Chris but you're wrong. The oil and coal was laid down before fungi and bacteria appeared on the scene. All plant forms are decomposed by the two and insect life forms now.

Pleased to meet you though.

Bill, from my privileged position as moderator I've discovered I've duplicated you.

To the best of my knowledge, hydro-carbons were the product of algae, one of the first plant life forms. Back in the seventies the Israelis had an algae plant producing crude like sludge. How far they went with it I don't know but trying to replicate a process that went on for billions of years is hard to say at the least.

Fungi and bacteria and wood

Scott, I have not looked far, but sources such as this indicate that fungi have been around for about the last billion years. As classic decomposer organisms, they can only live by having things to decompose, and the bulk of them are associated with land plants. They are soft-bodied, and leave no fossils easily identifiable as such.

Bacteria are as old as life itself. They were the first cellular organisms to appear on Earth, probably 3,800-3,500 million years ago.

Chris, milled wood fashioned into furniture etc would lock up carbon for as long as it was around. But the oldest piece of furniture that I am familiar with is an Elizabethan era dining table that a friend paid a small fortune for. Unfortunately, the oak it is made of has been subject to dry rot (caused by fungi).

Milling wood and building stuff out of it would help in the fight against climate change in proportion to the actual length of 'life' of the milled wood. Unfortunately, most of it is not around as houses, furniture etc long enough to make much difference.


Perhaps, Ian, I didn't go far enough. The point I was making was that as long as there were no other life forms around to consume algae it was free, once its life was extinguished, to fall to the bottom of the ocean.

Did a bit of research, this was interesting.

Not a very well-kept secret

Chris, when trees die they rot. Go into a forest and see for yourself. Fungus all over the place, producing carbon dioxide. Every bit of preserved timber will eventually rot or be burned.

Sure, some may be buried and become coal. But not much. And I don't think wood becomes oil.

CO2 from ethanol

 Bill: "...if we're going to power our machines with ethanol, how is that going to reduce CO2 emissions? Do the big producers of fuel ethanol contain the CO2 they produce? And if so, what do they do with it?"

Fuel whose store of chemical energy has come from plants recently grown puts CO2 into the air when burnt, but at least that CO2 was taken out of the air recently while the plants were growing. Trouble is, it is still CO2, indistinguishable chemically from CO2 arising from the burning of coal, the plant sources of which were alive hundreds of millions of years ago. However, if the world was 100% powered by solar and other 'renewables' including fuel from recently grown plants, as much CO2 would be being drawn from the air as was being added to it, and the CO2 load in the air would stabilise around a level where photosynthesis equalled respiration + combustion, which includes respiration by decomposer organisms. That will be the world that arises as fossil fuels decline to vanishing point, however long that takes. 

To my knowledge, no CO2 produced from combustion, other than in experimental systems, is being removed yet by industry. The smaller the industrial plant, the less cost-effective it would be. Ethanol producers are small beer beside BHP and Rio Tinto, and the latter two have not got it going in their plants yet.

Lavoisier's smoke and mirrors trick

Bill Avent:  "So you take a lump of carbon, set it alight, and not only get to use its heat, and end up with a pile of ash and a cloud of smoke, but you end up with three times the mass of carbon you started with?"

Not three times the mass of carbon, Bill. Three times the mass of the coal.  For a start, coal is not 100% carbon. The carbon in one tonne of coal, believe it or not, will combine with 2 tonnes of oxygen from the air (approximately) to produce 3 tonnes of carbon dioxide.

The first experiments on this phenomenon were carried out by the 'father of modern chemistry', Antoine Lavoisier. [1] He also produced the Law of Conservation of Mass, which as you infer, would be violated if you got three tonnes of carbon out of one.

However, I should point out to you and other readers an error that did manage to get past me in the n times I proof read The Furture of Carbon. The Montreal Protocol was opened for signature on September 16, 1987, not September 27, 2007. My apologies.

What weighs more, a tonne of feathers or a tonne of lead? Good question for the kids.

Try this one on them also: What weighs more, the pile of wood at the start of the winter, or the pile of ash at the end? They will inevitably say, "the wood." So you say: "Then where does all the weight go?" They will say, "up the chimney", if only because that's the only place it can go.

So you tell them: "you're dead right there."

Watch their reaction.

Farmers may be the answer to our C02 problems.

Ian, an excellent a well thought through piece. I had to read it twice to get all the information into my thick skull.

It is a pity that the Rudd government seems so determined to take Australia down the geosequestration path, probably wasting millions in the process.

I wonder if the C02 pipelines need to connected to C02 storage sites.

Surely it doesn't matter where we take the C02 out of the atmosphere as long as we do it.

Couldn't we store C02 in the soil, by rewarding farmers to contribute to carbon sequestration?

The benefits of rewarding farmers for contributing to carbon sequestration include the following:

  • Improved soil health, protecting our most precious national resource.
  • Increased soil fertility, boosting productivity and competitiveness
  • Better usage of water, reducing erosion, silting, and salination
  • Reduced danger of rising salt levels, lowering the water table
  • Reduced loss of topsoil to wind and runoff with 100% ground cover.
  • Increased farm incomes, increasing viability in volatile industries
  • Increased farm values, giving farm families financial flexibility
  • Foster growth in farm communities, providing employment opportunities and protecting social infrastructure

Given the following facts:

  • The terrestrial biosphere currently sequesters 2 billion metric tons of carbon annually. (US Department of Agriculture)
  • Soils contain 82% of terrestrial carbon.
  • "Enhancing the natural processes that remove CO2 from the atmosphere is thought to be the most cost-effective means of reducing atmospheric levels of CO2." (US Department of Energy)
  • "Soil organic carbon is the largest reservoir in interaction with the atmosphere." (United Nations Food & Agriculture Organisation) - Vegetation 650 gigatons, atmosphere 750 gigatons, soil 1500 gigatons
  • The carbon sink capacity of the world's agricultural and degraded soils is 50% to 66% of the historic carbon loss of 42 to 78 gigatons of carbon.
  • Grazing land comprises more than half the total land surface
  • An acre of pasture can sequester more carbon than an acre of forest.
  • “Soil represents the largest carbon sink over which we have control. Improvements in soil carbon levels could be made in all rural areas, whereas the regions suited to carbon sequestration in plantation timber are limited.” (Dr Christine Jones)

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