Huge supplies of cheap gas shatter peak energy fears
By Matt Ridley - from the Financial Post
The detection and exploitation of shale gas has been described as nothing less than a revolution in the world energy industry, promising to transform not only the prospects of the gas industry, but of world energy trade, geopolitics and climate policy. Some estimates of the gas recoverable from the Marcellus shale discovery in Pennsylvania alone are equivalent to 25 years’ U.S. consumption and worth potentially $2-trillion.
The Marcellus discovery alerted the world beyond the gas industry to shale gas. Similar shales exist on all continents. By one estimate, there are 688 suitable shale deposits in 142 basins, only a handful of which have yet been explored. It is unlikely that Marcellus will turn out to be the richest deposit in the world.
Initially, environmentalists welcomed shale gas. However, as it became apparent that shale gas was a competitive threat to renewable energy as well as to coal, the green movement has turned against shale. Its criticism is fivefold.
The first criticism is that the shale gas industry uses dangerous chemicals in fracturing, or “fracking,” the rocks that trap the gas, and that this process might contaminate groundwater. This criticism came about because of the industry‘s initial refusal to reveal the ingredients used in hydraulic fracking. Pressed by regulators, shale gas companies are now becoming more transparent about the chemicals in fracking fluid.
Typically, what goes down the well is 94.62% water, 5.24% sand, 0.05% friction reducer, 0.05% antimicrobial, 0.03% hydrochloric acid and 0.01% scale inhibitor. The actual chemicals are used in many industrial and even domestic applications. At high dilution, these are unlikely to pose a risk to human health in the event they reach groundwater.
But can they even infiltrate groundwater? The aquifers used for well water in states like Pennsylvania lie just a few hundred feet below the surface, whereas the shale gas is several thousand feet below. Seismic studies show that there is approximately one mile of solid rock between the fracking fissures and the aquifer.
The well pipe running down through the aquifer is encased in alternating layers of concrete and steel and is generally triple-encased down to the depth of aquifers (less than 500 feet). For the well to produce gas it is vital that there are no leaks of either gas or fracking fluids into the aquifer or any other strata, so it is not in the company‘s interest to allow this.
However, on rare occasions wells may fail through the loss of the drilling bit and have to be abandoned. In such cases, the well must be sealed with cement, but it is possible that this can be unsuccessful or that contamination can occur before it takes effect.
The industry contends that ground water contamination occurs much more frequently as a result of pollution unrelated to the shale-gas industry: agricultural run-off, oil spills from the transport industry, run-off from abandoned coal mines, and so forth. Wherever well water has been tested before and after gas drilling, no evidence has been found of groundwater contamination by fracking fluids.
Shale gas operations in the United States are heavily regulated and closely monitored. State regulators from Alaska, Colorado, Indiana, Louisiana, Michigan, Oklahoma, Pennsylvania, South Dakota, Texas and Wyoming have all asserted in writing that there have been no verified or documented cases of groundwater contamination as a result of hydraulic fracking. Read more...
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