I am in Panama! It is an awesome place. (Including the traffic at 5pm on a Monday. And the lack of sidewalks.) So, of course, I will talk about Japan.
A Japanese drilling ship, the Chikyu, recently extracted methane from hydrates 1,000 feet down in the Eastern
Nankai Trough. Methane hydrates, aka clathrates, are deposits of
natural gas trapped in ice. (OK, it’s not really ice, but what else would you call it?) They are not easy to extract. A good primer is here at Wonkblog.
How not easy to extract? Seriously not easy to extract. This blog likes cost numbers, and fortunately the Japanese consortium running the process provided them in 2008:
¥ per m3 | $ per MCF | |
Present construction costs | ¥ 92 |
$ 33.98 |
Assumed conditions | ¥ 46 |
$ 16.99 |
Volume 25% lower than expected | ¥ 174 |
$ 64.27 |
“Assumed conditions” means a threefold drop in construction costs. Worse yet, costs are extremely sensitive to volumes; produce less than expected, and profits go out the window. The low price of $16.99, meanwhile, is more than Japan currently pays for liquified natural gas (LNG).
Still, breakthroughs happen. Maybe Japanese engineers can move beyond proof-of-concept tests to cost-effective methane extraction. What then?
Well, do not worry about the amount of methane that can be extracted and burned. That is entirely a red herring. The world has plenty of cheap conventional natural gas to burn between now and 2100. Unless the hydrates drop in price way more than anyone expects — say, down below $6 per MCF — then commercial exploitation will not cause the world to burn natural gas any faster than it would have otherwise. I very much fear global warming, and once natural gas has killed coal dead then natural gas will become the problem, but the hydrates won’t make a damned bit of difference unless you believe that we will be burning methane for power into the 22nd and 23rd centuries.
OK, so no worries in burning methane from hydrates. (More specifically: no additional worries than we currently have.) But do worry! I have been talking about this with my friend Will Baird out in California. The problem is that not all of that methane will be burned. Maybe not even most. Maybe even catastrophically little.
The Department of Energy reports that the Nankai Trough has 16 to 27 trillion cubic meters of methane hydrates. Methane is approximately 21 times more potent as a green house gas as CO2. If you were to dump all of the Nakai Trough's hydrates into the air at once, it would the equivalent 20 years worth of U.S. methane emissions all at once.
The good thing is that methane falls out of the atmosphere quickly. The bad thing is in the middle sentence of the above paragraph. A catastrophic emission of the Nankai hydrates would cause a short painful spike in temperatures ... and given how close the Earth is to climatological tipping points, it could push us over.
That probably won’t happen, but you’d be crazy not to think about it. What most likely would happen is that commercial exploitation would destabilize the deposits. The Japanese want to remove ice from under sediment. In a geologically inactive zone, that is mildly annoying, but, well, Japan is not in a geologically inactive zone. Even without the effect of quakes, if the Japanese use warm(er) water to melt and separate the gas from the ice, then surrounding ice could be destabilized. A catastrophic release may be unlikely, but the probability of large-scale methane releases is too high for comfort.
And some degree of methane release is inevitable. So far, we do not know what the capture ratio will be ... and we probably won’t until there is a commercial test.
But let me finish with two pieces of good news. First, the process is not likely to be economically competitive; we will probably therefore never have to worry about the environmental effects. Second, this is a government-funded project, so even if it is competitive there will be fewer vested interests insisting on development.
In short, the hydrates are scary if you want to leave this world to your grandchildren ... but the obstacles to development are high enough that they will likely not be developed.
Glad I could help with this one.
The amusing flipside of this is if we tap, mine and remove the hydrates(*), then they can't naturally destabilize. Which they do. So, if we can do this safely, we're making the world a slightly safer place.
Whatever heating from the Ch4 will not disappear quickly though.
Its a low likelihood.
The capture ratio is really important. For that matter, what is it for fracking?
Posted by: Will Baird | March 19, 2013 at 02:16 PM
Fracking has around 91% capture.
Checking on the calthrates.
Posted by: Will Baird | March 20, 2013 at 02:18 AM
AFAIK, that 9% figure for fracking is from one NOAA study in Utah. People across the river at HKS don't believe it travels; they stick to the EPA estimate of 2.4%. If the NOAA study is confirmed outside of the Uintah Basin, then we'll have a bombshell that you can be sure I will blog about.
Baseline to be better than coal is around 3½ percent.
Posted by: Noel Maurer | March 20, 2013 at 06:00 AM
Query: how is it a bombshell?
Clathrates are a lot worse, iirc. I saw a number once and I even had it on the blog somewhere, but...I can't seem to find it. Its probably before I started using key words.
Posted by: Will Baird | March 20, 2013 at 08:02 PM
If methane leakage goes hits 3½% of production, then natural gas becomes as bad as coal in terms of force heating the Earth.
If leakage goes to 9%, then not only do the greenhouse benefits of switching from coal to natural gas go out the window, but the U.S. becomes a significantly worse emitter.
It would be a bombshell, and bad. I do not know if anyone as calculated yet just how bad.
Posted by: Noel Maurer | March 20, 2013 at 09:11 PM