Otways Carbon Capture: Dumb idea?

We already have a proven and widely used means of carbon capture and storage that does not threaten a massive disaster as pumping CO₂ underground does, yet the latte drinkers who consider themselves green hate it.

Ideally, carbon capture should be to a solid that will not degrade over time, and needs minimal technology to contain it.  Non-biodegradable plastic bags meet such requirements.  Further, if they are collected into one spot, they can be retrieved later, when technology allows efficient conversion to other useful items.

Pumping CO₂ underground, however, is something that could be worrying, especially the current project in the Otway basin in my old stomping ground of South-Western Victoria.

Natural CCS disasters

There are numerous limnic eruption disasters where CO₂ has wiped out all animal life in a fairly large area, the 1986 Lake Nyos event in Cameroon being perhaps the best known.

The CO₂-rich cloud was expelled rapidly from the southern floor of Lake Nyos. It rose as a jet with a speed of about 100 km per hour.  The cloud quickly enveloped houses within the crater that were 120 meters above the shoreline of the lake.  Because CO₂ is about 1.5 times the density of air, the gaseous mass hugged the ground surface and descended down valleys along the north side of the crater.  The deadly cloud was about 50 meters thick and it advanced downslope at a rate of 20 to 50 km per hour.  This deadly mist persisted in a concentrated form over a distance of 23 km, bringing sudden death to the villages of Nyos, Kam, Cha, and Subum.

Lake Kivu, which is much bigger than Nyos, and has 2 million people around it’s shores, is considered dangerous… so dangerous, that it is one lake under consideration for "outgassing" – pumping CO₂ from the bottom of the lake into the air.

Mind you, the biggest CO₂ eruptions are linked to massive global warming at the start of the Eocene, and the mass global extinctions of the Permian.

Otway Basin Project

The A$30 million pilot project to inject CO₂ into a depleted gas field in the Otways basin might create conditions leading to something akin to a phreatic eruption, as the Otways are in a region that, on a UWA page, "was an active volcanic province in relatively recent times", a few thousand years ago, and with Richter 5.3 earthquakes hitting Cape Otway in my own lifetime (24 Dec 1960), and Warrnambool in 1903. (See map of earthquake epicentres in South-Western Victoria.)

CO2CRC.com.au, running this project, publishes a Lake Nyos fact sheet, and explains that the Otways are different (yes, of course!), and that therefore the Otways project is safe (not necessarily, because other mechanisms could be involved).  Perhaps CO2CRC were setting up a straw-man objection?  CO2CRC’s promotional materials about CCS being safe mention risks from heat and earthquakes as being real, but not a problem.  I’m more skeptical: and remember, we are talking about storage of geologically significant amounts of CO₂ for a geologically significant time.

Indeed, those promotional materials indicate there are no guidelines for considering seismic safety yet in place:

Storage sites are selected because they are inherently stable, have effective seals, and are located away from areas of seismic instability. Criteria for considering seismic effects in site selection are being developed.

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From a 2004 ABC Science report:

Bernie Joyce, from the University of Melbourne, presented a paper on volcanic hazards today at the 17th Australian Geological Convention of the Geological Society of Australia held in Hobart, Tasmania.  Volcanoes in Victoria, New South Wales and Queensland could erupt at any time, he told ABC Science Online ahead of the conference.

It’s also worth noting that many scientists are worried about clathrates (sequestered carbon in undersea "ice") causing massive releases of CO₂, a positive feedback component of global warming, and linked to mass extinctions in the Permian, and the global warming at the start of the Eocene.

So, if CCS is an untested technology, and little thought is given to the dangers of containment failure (at least with a nuclear accident there are some medical treatments available – with CO₂ eruptions everything is dead in seconds), then either we assess the dangers properly (a large and hot explosion simulating earthquakes and/or vulcanism near the pilot project would be required) or we’d be better off burying plastic bags.

Personally, rather than encourage activities (Carbon release) we know to be harmful by the promise of an unproven technology, I’d rather the money was spent on efficiency, wind/hydro/solar, or installing a Toshiba 4S Personal Reactor (picture, US Dept of Energy notes, and on sale soon costing half grid cost) in every residential block.

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See Also:

• Otways Project
  • CSIRO Briefing
  • Otway project overview from CO2CRC.com.au
  • CO2CRC.com.au’s media launch
  • CO2CRC.com.au’s promotional material about safety
  • Ministerial Announcement of Otways project
  • C02CRC at Melb Uni Chemical Engineering , including list of CO2CRC partners (which includes "Origon Energy", and the link to the no-such-site origonenergy.com.au – great QA!)
• Geology of Otway region
  • Volcanoes and Earthquakes in South Eastern Australia – University of WA
  • South Western Victorian Earthquakes sourced via nre.vic.gov.au – Cape Otway is the southernmost tip of land on this map, with the Otway ranges extending northwards halfway to Colac.  You’ll find a relative of mine in almost every small town south of the Hamilton Highway between Geelong and Mortlake.
• Selected Publications on the Cameroon Lakes
• Volcanic Lakes and Gas Releases (US Geological Survey)
• International Volcanic Health Hazard Network CO₂ page has a table of CO₂ related mortalities
• "Release of methane from a volcanic basin as a mechanism for initial Eocene global warming" in Nature doi:10.1038/nature02566
• Clathrate Gun Hypothesis, which shows how "natural" CCS might be highly dangerous in geological time, with no hint that pumping geologically-significant amounts of CO₂ underground is really any safer as far as climate change is concerned.
• While Melbourne Uni ChemEng’s backgrounder on CO2CRC states "First steps in the hydrogen economy will be fed by transforming methane derived from coal or natural gas, but this also generates considerable quantities of CO2." and " Therefore any move towards a hydrogen economy will be dependant on the successful application of sequestration technology", this is not necessarily true, as a hydrogen economy might involve electrolysis of water (powered by geothermal energy).
• On a side note, CO₂ sequestration would be less of an issue if we had improved use of non-inflammable renewable energy, and there is a fairly extensive page on wikipedia: "Renewable energy commercialisation in Australia". (Mind you, socialist that I am, it’s an essential service, so I’d limit the capitalism but to paying producers, and recovering some costs from consumers.