Tuesday, December 26, 2006

Plugging Leaks

Pipelines are among the most prosaic elements of our energy infrastructure. Big, controversial ones crossing national frontiers get a lot of attention, but the rest generally hum along, year after year, unnoticed unless they experience a leak. A new technology offers the possibility of plugging pipeline leaks in much the same way our bodies heal cuts. An article in Technology Review describes how this technique was developed by a Scottish engineer and recently tested by a big oil company under real-world conditions, undersea. What intrigues me the most about this idea, however, is not just the highly beneficial prospect of reducing the environmental damage caused by oil spills from pipelines, but how a fully-developed self-patching technology could reduce the risks associated with future oil development in sensitive areas, and expand our potential supply base.

It would be hard to imagine our present industrialized world without energy pipelines. They make it possible to carry large volumes of petroleum and its products long distances, very inexpensively. Moving the same volumes for comparable distances overland by rail or truck would be immensely more intrusive, hazardous, and expensive, and it probably wouldn't have happened, along with a good deal of the energy use that pipelines have facilitated. That's even more true for natural gas. (You can take that as a benefit or drawback of their development, depending on your viewpoint.)

One of the biggest problems with pipelines is not the risk of a catastrophic rupture, which occur rarely and are immediately evident to operators, but of smaller leaks that can create serious localized environmental damage before being detected, requiring expensive cleanups. Department of Transportation data indicate that, on average, just under 100,000 barrels per year of "hazardous liquids"--mostly oil and its products--has leaked from US pipelines since 2001, the equivalent of an Exxon "Valdez" every three years. Reducing this volume would have very significant benefits for both the industry and the environment, and the artificial platelet technology described in the article is a clever answer to this problem.

Plugging leaks this way could have applications beyond liquid pipelines, as well. Similar technology might be deployed on oil tankers and remote storage tanks, limiting leaks of oil or other dangerous fluids from a variety of sources. If the platelets could be adapted to work in natural gas pipelines, they might even address a significant source of greenhouse gas emissions. Methane emissions from natural gas systems accounted for roughly 2% of all US greenhouse gas emissions last year, according to the Department of Energy.

The value of a fast-acting anti-leak system could be even greater in changing perceptions about the risk of leaks in sensitive areas. Something like this would have to go through a lot of testing and experience in existing installations, before it would be deemed reliable enough to alter the balance of risks associated with developing oil fields in the arctic, for example. Nor would this be universally welcomed, since there are many who oppose such development on general principles, rather than on its actual track record and risks. But as I've suggested before, any serious discussion of energy security must consider expanded oil drilling as a serious option, weighing its environmental impact against that of alternative hydrocarbons, such as coal liquefaction or oil sands extraction. Self-healing pipelines would enhance oil's side of this ledger substantially.

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