Earlier posted May 10, 2012, at Science 2.0 Seeing Green. Posted with the author's permission.
By Holly Moeller
Last week, word came from Prudhoe Bay that sent chills through me as surely as if I’d been standing in the Alaskan North Slope drilling outpost myself. The United States Department of Energy – in collaboration with energy giant ConocoPhillips and the Japanese nationalized minerals corporation – reported success from a month-long test extraction of methane gas tucked into an icy lattice below the permafrost.
These methane hydrates – also called methane clathrates, after the particular crystalline structure of the ice matrix – are found in cold regions (like the Arctic, where low temperatures keep the permafrost soil layer frozen year-round) and off continental shelves (where pressure from a thick blanket of water stabilizes the compressed gas).
Though testing to reveal the full extent and nature of these gas deposits has only just begun, methane hydrates are already making headlines as the next big energy source.
The US Geological Survey estimates that there’s twice as much burnable carbon hiding in hydrates as in all other known fossil fuel deposits worldwide. And since methane gas burns hot and clean – giving off 33% more energy per carbon dioxide molecule emitted as petroleum, without the nasty nitrogen and sulfur oxides that come from coal – ears around the world have perked up.
In 2006, China pledged $100 million to hydrate exploration. In 2008, Japan and Canada completed a six-day test drill in the Mackenzie Basin. And now that this year’s test results are looking good, Secretary of Energy Steven Chu says that domestic gas prices could drop 30% by 2025.
As an added bonus, methane extraction traps CO2. The latest technology pumps the most notorious greenhouse gas into the ground, where it replaces methane in the ice matrix. The displaced methane is then pumped to the surface and – in the DoE’s (and, undoubtedly, ConocoPhillips’) vision – down pipelines to heat homes in the Lower 48.
Plus, argue supporters, climate change projections indicate that rising temperatures may release much of that methane anyway. If the permafrost thaws or the ocean warms, vast tracts of icy clathrates could melt, outgassing methane – which has 20 times the warming potential of CO2 – into the atmosphere, further accelerating climate change. This is one of the most feared positive feedback loops known to climate scientists.
So wouldn’t it be nice if we could turn some of that methane into carbon dioxide ahead of time?
I don’t think so.
Burning fossil fuels – oil, coal, and natural gas – put us into our tenuous climatic position in the first place. Any CO2 we sequester during methane hydrate extraction will quickly be replaced through burning of the extracted methane. And the CO2 trap is only temporary: warmer polar temperatures will free it as surely as the presently trapped methane scientists are so concerned about.
Add to this the issue of scale. Given that commercialization of methane hydrate extraction is still a political pipe dream, we’re unlikely to process any significant portion of the 320 quadrillion cubic feet of methane scattered in hydrates around the country.
Now to don our economic hats. Increased supply and decreased costs only drive up demand. Say we can, as the DoE promises, double our natural gas supply and effect dramatic price cuts by using only 1% of domestically available methane hydrates. This quick fix of another carbon-based fuel will only delay our ultimate sustainability reckoning.
Methane hydrates, no matter how vast their supply seems, are just another nonrenewable resource. A boom in gas production will add years – maybe decades – to the difficult but necessary transition to renewable energy sources. And in the meantime, we’ll be doing plenty of damage to our environment both globally – through additional greenhouse gas emissions – and locally – by drilling in sensitive ecosystems.
In the last decade, we’ve fought plenty of environmental battles over how and where to drill for oil. We’ve seen the consequences – Deepwater Horizon and the Gulf of Mexico 2010 spill, for example – of pushing our technological limits towards harder and harder to reach deposits.
And now we want to grasp at something even more risky, at mineral formations that, when destabilized, cause explosions and landslides.
I’m afraid that the laws of economics – especially in a country that will invest $6.5 million this year alone (plus an additional $5 million, pending Congressional approval) on methane hydrate recover research – will once again favor Sarah Palin’s mantra, “Drill, baby, drill.” Because as surely as methane is trapped within its lattice of ice, we’ve trapped ourselves in a spiderweb of fossil fuel dependency. Unlike methane, however, it seems even climate change can’t force us out.
These methane hydrates – also called methane clathrates, after the particular crystalline structure of the ice matrix – are found in cold regions (like the Arctic, where low temperatures keep the permafrost soil layer frozen year-round) and off continental shelves (where pressure from a thick blanket of water stabilizes the compressed gas).
Though testing to reveal the full extent and nature of these gas deposits has only just begun, methane hydrates are already making headlines as the next big energy source.
The US Geological Survey estimates that there’s twice as much burnable carbon hiding in hydrates as in all other known fossil fuel deposits worldwide. And since methane gas burns hot and clean – giving off 33% more energy per carbon dioxide molecule emitted as petroleum, without the nasty nitrogen and sulfur oxides that come from coal – ears around the world have perked up.
In 2006, China pledged $100 million to hydrate exploration. In 2008, Japan and Canada completed a six-day test drill in the Mackenzie Basin. And now that this year’s test results are looking good, Secretary of Energy Steven Chu says that domestic gas prices could drop 30% by 2025.
As an added bonus, methane extraction traps CO2. The latest technology pumps the most notorious greenhouse gas into the ground, where it replaces methane in the ice matrix. The displaced methane is then pumped to the surface and – in the DoE’s (and, undoubtedly, ConocoPhillips’) vision – down pipelines to heat homes in the Lower 48.
Plus, argue supporters, climate change projections indicate that rising temperatures may release much of that methane anyway. If the permafrost thaws or the ocean warms, vast tracts of icy clathrates could melt, outgassing methane – which has 20 times the warming potential of CO2 – into the atmosphere, further accelerating climate change. This is one of the most feared positive feedback loops known to climate scientists.
So wouldn’t it be nice if we could turn some of that methane into carbon dioxide ahead of time?
I don’t think so.
Burning fossil fuels – oil, coal, and natural gas – put us into our tenuous climatic position in the first place. Any CO2 we sequester during methane hydrate extraction will quickly be replaced through burning of the extracted methane. And the CO2 trap is only temporary: warmer polar temperatures will free it as surely as the presently trapped methane scientists are so concerned about.
Add to this the issue of scale. Given that commercialization of methane hydrate extraction is still a political pipe dream, we’re unlikely to process any significant portion of the 320 quadrillion cubic feet of methane scattered in hydrates around the country.
Now to don our economic hats. Increased supply and decreased costs only drive up demand. Say we can, as the DoE promises, double our natural gas supply and effect dramatic price cuts by using only 1% of domestically available methane hydrates. This quick fix of another carbon-based fuel will only delay our ultimate sustainability reckoning.
Methane hydrates, no matter how vast their supply seems, are just another nonrenewable resource. A boom in gas production will add years – maybe decades – to the difficult but necessary transition to renewable energy sources. And in the meantime, we’ll be doing plenty of damage to our environment both globally – through additional greenhouse gas emissions – and locally – by drilling in sensitive ecosystems.
In the last decade, we’ve fought plenty of environmental battles over how and where to drill for oil. We’ve seen the consequences – Deepwater Horizon and the Gulf of Mexico 2010 spill, for example – of pushing our technological limits towards harder and harder to reach deposits.
And now we want to grasp at something even more risky, at mineral formations that, when destabilized, cause explosions and landslides.
I’m afraid that the laws of economics – especially in a country that will invest $6.5 million this year alone (plus an additional $5 million, pending Congressional approval) on methane hydrate recover research – will once again favor Sarah Palin’s mantra, “Drill, baby, drill.” Because as surely as methane is trapped within its lattice of ice, we’ve trapped ourselves in a spiderweb of fossil fuel dependency. Unlike methane, however, it seems even climate change can’t force us out.
Editor's notes:
- Methane's global warming potential (GWP) is more than 130 times that of carbon dioxide over a period of ten years, as described in the post Methane in the Arctic.
- The Energy Department's announcement can be viewed at: http://energy.gov/articles/us-and-japan-complete-successful-field-trial-methane-hydrate-production-technologies
- Methane's global warming potential (GWP) is more than 130 times that of carbon dioxide over a period of ten years, as described in the post Methane in the Arctic.
- The Energy Department's announcement can be viewed at: http://energy.gov/articles/us-and-japan-complete-successful-field-trial-methane-hydrate-production-technologies
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