January 8th, 2013

The best chart I’ve seen for some time:

Seismic cloud from Habanero-4 EGS well test

What it describes is quite complex, so bear with me. A small Australian geothermal company, Geodynamics, has been drilling deep experimental wells at a desert site called Innamincka. These are EGS – “hot dry rocks” wells, not hydrothermal; the hot water reservoir isn’t there waiting for you, it must be engineered. After you finish drilling your well into a very large lump of hot granite, you inject water down it at high pressure – 2,000 psi or so, a fifth of that used in gas fracking. The water expands existing tiny cracks – microfractures – and with luck creates a web of channels as far as a second, extraction well. Pump up that now superheated hot water, expand to steam, and run it through a turbine. That’s an EGS geothermal plant: 24-hour, unobtrusive, zero-carbon, safe, long-lived. But still experimental, and financially nail-biting. Getting the geology right is critical and very difficult.

The crack-making creates microshocks. These can be detected with sensitive equipment (and, rarely, without them). The chart is a record of all the microshocks detected during a test period of three weeks from a well called Habanero-4. It captures:
- the relative magnitudes of the microshocks (by the size of the spheres)
- their spatial location in two-and-a half dimensions (the depth is roughly indicated by the occlusion of the deeper bubbles by the shallower)
- the development of the reservoir stimulation over time, using colours.

The grey dots aren’t explained, I think they must be the pattern from a previous test using Habanero-1 as the injector well. Here, Fig. 2.

You can see immediately that the fracture zone spread with time some distance north from the well – perhaps a surprise to the drillers, as the previous wells are south of Habanero-4.

The chart, like a cloud chamber experiment, lets our visual brains synthesize an immense amount of information. The software is presumably 3D, so you could view the seismic cloud from the side, or play a speeded-up movie.

A great deal is riding on a very few active EGS projects. Hydrothermal resources – underground hot water – are easier to tap but tectonically localised. (There are plenty in the Rift Valley, Central America, Iceland, Indonesia, and the Philippines). Deep lumps of hot granite are more or less everywhere, enough to give us all the backup we could ever need for cheaper wind and solar energy. The technology gets marginal support: the US DoE funds just two small projects into cheaper hard-rock drilling, spallation with Potter Drilling (there’s also a Swiss team at Einstein’s ETH in Zurich), and laser assistance with Foro Energy. Peanuts.

The coloured bubble cloud chart could be used to show spatial trends for a variety of discrete but causally linked events: infections, crimes, bankruptcies, foreclosures, innovations.

Here´s an unrelated use of bubbles to make a point:

It´s clever agitprop, but of course you don´t really learn anything.

16 Responses to “Hogmanay bubble clouds”

  1. Allen K. says:

    Not to sidetrack too much, I hope, but it’s really annoying that that agitprop doesn’t mention how much smaller is a New Yorker’s carbon footprint than a rural American’s.

    • John R says:

      If you were to calculate all the energy to build N.Y., run its total infrastructure (energy, roads, high-rises, gazillion computers, subways including water pumping, etc.), feed & clothe all its people from off-site producers, and dispose of all your waste (except carbon dioxide, of course!), then divide by the number of inhabitants, my guess is you’d be in for a surprise. We are retired gentleman/woman subsistence farmers, heat with blown-down wood on our 10 acre county property, have no air conditioning, produce electricity with solar panels, pump our water from a well, and heat water with solar water heaters. Which of us is more resilient in the event of emergencies of various sorts, do you suppose? I imagine your carbon footprint is very similar to ours, all things considered. I’ve done plenty of carbon footprint analyses, and have some idea what goes into them, and for northerners (us included) it’s mainly the fact of living in a cold climate that matters.

      • Barry says:

        No, because rural/suburban American spends a sh*tload on transportaton (when it takes a car to do anything, one burns a lot of CO2). Your example is not normal; most people don’t rely on woodstoves and solar.

        As for resilience, that’s another thing whatsoever.

      • John Beaty says:

        A classic example of trying to use an outlying specific to counter a well-researched generality. Do you consult with the GOP?

        • prognostication says:

          Despite some of the weird resilience stuff, his point is actually somewhat valid. This is a much more complicated issue than the popular understanding suggests.

          Do emissions related to farming get charged to rural areas where production occurs, or where the food is consumed? Who is charged for the transport of food? Why?

    • Maynard Handley says:

      Dividing by population to get a per capita number may make you feel better, but in the absence of any serious attempt to reduce the number of capitas, it’s not just pointless, it’s positively destructive.
      The actual planetary effects don’t care about per capita numbers, they care about the totals.

  2. Potifar says:

    I think you definitely DO learn something from that video. It’s actually pretty damned impressive. And I think that if more people saw that they might think a little differently about CO2 emmissions and such. Now, of course, one thing that the video does that isn’t quite “right” is that the gas piles up on top of the city when in actuality it floats away…….so make one showing a years worth of all emissions on earth floating around in the atmosphere?

  3. Byomtov says:

    Could someone explain to this non-scientist what it means to say a ton of carbon dioxide will fill a sphere 33 feet across? It’s a gas.

    • Tim says:

      There’s a note at the end of the video that suggests their 33 foot diameter sphere comes from the density of CO2 at 59°F and “standard pressure” — which I guess means the average atmospheric pressure found at NYC. The volume of a gas is effected by temperature and pressure.

    • harrync says:

      According to the data slide at the end of the presentation, at normal temperature and pressure, carbon dioxide weighs 1.87 kilograms per cubic meter. This works out to roughly 500 cubic meters per ton; or put another way, a ton of carbon dioxide gas would fill a cube about 8 meters [about 25 - 30 feet] on a side; that is, about the equivalent of a sphere 33 feet in diameter. Just some rough calculations in my head, but it looks like their 33 foot sphere of gas is about right.

    • Byomtov says:

      OK. Thanks.

  4. koreyel says:

    The larger point here is that our political leaders are moving in slo-mo.
    Let me share a quote, and then a thought experiment based on it:

    The wind whistling across the wide-open plains of just three U.S. states – North Dakota, Kansas, and Texas — could power the entire nation. But without massive investments in new high-voltage power lines to move electricity from the Great Plains to the heavily populated coasts, windmills are useless.

    Now for a thought experiment:

    If CO2 not only warmed planet but also affected human brains, that is if in concentrations greater than 450 ppm it caused physiological changes that made people politically more liberally, perhaps even communistic, would our energy oligarchs be building windmills in the great plains and laying thick cables with incredible speed?

    I think you know the answer to that. They’d be killing it. Overtime pay for workers even…
    Which is all to suggest again that the answers to global warming are out there waiting to be seized.
    What we lack is political will. Most of the reason we lack that will is because of our filthy criminal oil and coal oligarchs.
    J’accuse the Kochs of crimes against humanity!

    Quote source: http://www.energyrealities.org/content/why-we-need-a-smarter-grid/erp92C855B20D65D16CB

  5. Trenton C. says:

    I appreciate the shout-out to AltaRock’s Newberry EGS demonstration in your post, “you inject water down it at high pressure – 2,000 psi or so, a fifth of that used in gas fracking.” However, I feel obligated to point out that 2000 psi well head pressure was a specific value calculated for an injection well on a volcano in central Oregon, USA. The Newberry well is much shallower than the Australian project (3 km versus 5 km), and the tectonic/volcanic regime is completely different (young rocks in an active volcanic arc compared to old granites). Suffice it to say, that the well head pressures used in the Geodynamics project are probably much higher than 2000 psi, closer to the 10000 psi number you also quote.

    Still EGS is an exciting business to be in and we wish our colleagues in Australia continued success. If your readers want to check out the status of our EGS project, please visit: blog.newberrygeothermal.com

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