I recently received an e-mail from the normally level-headed National Academy of Sciences alerting me to the great potential of methane hydrates in fixing the climate and meeting our future energy needs.
Natural gas, composed mostly of methane, is the cleanest of all the fossil fuels, emitting 25-50% less carbon dioxide than either oil or coal for each unit of energy produced. In recent years, natural gas supplied approximately 20-25% of all energy consumed in the United States. Methane hydrate is a potentially enormous and as yet untapped source of methane. The Department of Energy’s Methane Hydrate Research and Development Program has been tasked since 2000 to implement and coordinate a national methane hydrate research effort to stimulate the development of knowledge and technology necessary for commercial production of methane from methane hydrate in a safe and environmentally responsible way.
Realizing the Energy Potential of Methane Hydrate for the United States evaluates the program’s research projects and management processes since its congressional re-authorization in 2005, and presents recommendations for its future research and development initiatives.
There’s no immediate need to worry about all that ice-bound methane on the ocean floors getting loose to wreak havoc with the climate.
For most parts of the ocean, melting of hydrates is a slow process. It
takes decades to centuries to warm up the water 1000 meters down in the
ocean, and centuries more to diffuse that heat down into the sediment
where the base of the stability zone is. The Arctic Ocean may be a
special case, because of the shallower stability zone due to the colder
water column, and because warming is expected to be more intense in
high latitudes.
Well, OK, the Arctic Ocean may be a special case, but I wouldn’t worry just now about all that methane scientists discovered bubbling out from the sea floor west of the Svalbard archipelago, which lies north of Norway. No doubt you’ve got enough to worry about as it is. In any case, technology will fix this degassing problem—human ingenuity can fix anything! For example, we could simply affix a huge sealed tarp over the area of methane release to capture the gas and then pipe it to wherever we need it.
Unfortunately, our Wet Dream of exploiting every hydrocarbon on the planet must be postponed while we study the problem. Still, there are no gotchas that will prevent that Dream from coming true.
Research on methane hydrate to date has not revealed technical challenges that the committee believes are insurmountable in the goal to achieve commercial production of methane from methane hydrate in an economically and environmentally feasible manner. However, many scientific and engineering questions in methane hydrate research remain to be answered before it will be possible to achieve commercial production. When this knowledge is available, informed decisions can be made as to whether or not to proceed with the commercial exploitation of methane hydrate.
The methane hydrate resource “pyramid” concept qualitatively appraises the distribution of the global methane hydrate resource by the size and type of the occurrence (deposit) and evaluates which of those hold the greatest economic potential for development. Resources near the top of the pyramid (Arctic and marine sands) are of higher reservoir quality and estimated percentage of recoverable resource, although they represent a smaller in-place resource volume than reservoirs at the bottom of the pyramid that represent fine-grained sediments (silts, shales, and muds).
We must consider The Importance of Methane Hydrate to the Nation.
Ensuring reliable sources of natural gas is of significant strategic interest to the United States… Natural gas is the cleanest of all the fossil fuels, emitting from 25 to 50 percent less carbon dioxide than either oil or coal for each unit of energy produced. In recent years, natural gas has supplied approximately 20-25 percent of all energy consumed in the United States.
Accumulations of methane hydrate, a solid form of natural gas, may represent an enormous source of methane [See the Figure above]… Although the estimated total global volume of methane in methane hydrate is still debated, generally acknowledged estimates yield figures between 2 and 10 times greater than those of technically recoverable conventional natural gas resources. The existence of such a large and as-yet untapped methane hydrate resource has provided a strong global research incentive to determine how methane from methane hydrate might be produced as a technically safe, environmentally compatible, and economically competitive energy resource.
Although methane is a cleaner-burning energy source than other fossil fuels, it is itself a significant greenhouse gas, about 25 times more potent per molecule than carbon dioxide on a 100-year basis. Thus, understanding the potential environmental impacts of methane hydrate degassing and the seafloor hazard (“geohazard”) potential resulting from methane hydrate dissociation, whether through natural processes or through oil and gas drilling and production, are also important as its potential for commercial production is considered and tested.
Well, of course, this makes sense. We wouldn’t want to inadvertently disturb a big patch of methane hydrates, which might lead to the release of a shitload of gas into the water column, which would eventually lead to its bubbling out of the sea and into the atmosphere.
You see, if the methane in ocean floor hydrates gets loose, that’s much, much worse than if we successfully capture it, pipe it somewhere and burn it. In this latter case, we only get the carbon emissions from burning the “pure” natural gas (CH4), not the full-blown greenhouse effects of unadulterated methane in the atmosphere, which converts to CO2 over time there—it’s 25 times more potent per molecule [as a greenhouse gas] than carbon dioxide on a 100-year basis.
Methane bubbles escaping from the sea floor
Methane hydrates are stable under low temperatures and high pressures. So, I guess you could say that by capturing & burning the natural gas in ocean floor hydrates, we would be actually saving the planet from the future ruin we might incur if the deep oceans were to warm sufficiently—due to the burning of fossil fuels like natural gas—to cause natural degassing.
Got it?
Perhaps you were a bit concerned for a little while here about the consequences of exploiting methane hydrates. But as I’ve just explained to you, there’s no need to worry about it—it’s all good!
