Monday, October 19, 2009

energy crisis postponed as new gas rescues the world?

ODAC | It is hard to know where to begin regarding Ambrose Evans-Pritchard's article entitled "Energy crisis is postponed as new gas rescues the world." But since the speculative world he invokes has more to with Alice In Wonderland than the hard reality of engineering and science, let us begin - at the end.

Evans-Pritchard caps his evangelistic encomium with this: "I am not qualified to judge where gas excitement crosses into hyperbole. I pass on the story because the claims of BP and Statoil are so extraordinary that we may need to rewrite the geo-strategy textbooks for the next half century."

He admits his lack of gas qualifications but surely he is enough of a journalist - and an economist - to ask some basic fact-checking questions. What none of the boosters want to talk about is the reality of shale gas. It is true that there is most likely a lot of shale gas around, especially in the United States, but after this, the story goes down a rabbit hole. Shale gas is not like the conventional gas finds that gave the US vast supplies of cheap methane. Shale gas is locked in until the rocks holding it are fractured in a process known as hydro-fracing. This requires a lot of work, a lot of wells, a lot of water (2 - 5 million gallons per well), and some rather unpleasant chemicals. Having made all this effort, the production decline rates look like the cliffs at Beachy Head. Within two years production has typcally dropped by 80%.

Not surprisingly therefore, these expensive wells have an average commercial life of less than eight years. Worse still, in August of this year, World Oil pointed out that total production of many wells was only a third of what operators had predicted. Furthermore, of the two dozen or so shale plays in the US, Barnett appears to have the best geological profile and is responsible for 80% of current shale gas. Many of the other plays have much lower gas content density, which would likely mean yet more wells and more fracing for less gas.