A report by the US Energy Information Administration last spring estimated the amount of recoverable natural gas within shale formations accessible in Europe with today’s technology was 624 trillion cubic feet—much higher than previous estimates. (The U.S., by comparison, is estimated to have 862 trillion cubic feet currently know and recoverable natural gas). Recently, the European Centre for Energy and Resource Security (EuCERS) based in Kings College in London released a study that estimated, "Europe's unconventional gas resources might be able to cover European gas demand for at least another 60 years.” Last week, Lichfield-based energy exploration firm Cuadrilla Resources estimated that some 200 trillion cubic feet of natural gas is stored within the shale rock beneath northwest England. The 200 trillion cubic feet is "gas in place" and is not the same as the recoverable volume of gas, but even if only a fraction of the shale gas is recoverable that increases the volume of gas that is recoverable with current technology significantly.
Until recently there was no economically feasible way to extract shale gas. However, in the past decade this has changed. Advances in horizontal drilling which allows a vertical well to turn and run thousands of feet laterally through the earth combined with advances in hydraulic fracking, the pumping of millions of gallons of water laced with proprietary chemicals into shale at high pressure to release the natural gas stored in the pore spaces have increased our ability to recover natural gas from that shale. An increase in the price of natural gas has spurred the development of the natural gas wells that could not have been viable without advances in drilling and fracking.
Fracking has been employed in the United States since the 1990s allowing energy producers to tap shale gas deposits previously considered almost useless. Production from those wells now contributes nearly a quarter of the United States gas supply, driving down prices for consumers. But concern and criticism of the practice has been growing even as it spreads. Exxon Mobil is drilling in Germany’s Lower Saxony. ConocoPhillips has joined a small firm based on the Isle of Man, to explore a large tract of land in Poland. Austria’s OMV is testing geological formations near Vienna. Shell is targeting Sweden. Earlier this year, France banned hydraulic fracturing despite the potential for extensive shale gas development in Southern France. In a radio interview France's environment minister Nathalie Kosciusko-Morizet, said that fracking “is not something we want to use in France. Shale gas is the same as any other gas. What poses a problem is the technology used."
Though the energy companies are beginning to gather baseline data for drinking water wells in the areas being fracked, the data collection is neither ongoing nor broad enough. The data that is being collected is not adding to the base of knowledge, but rather I suspect to demonstrate that stray gas was a pre-existing condition of the drinking water wells. What is needed is a slow development of shale gas resources to allow careful monitoring and data collection of the potential impacts to our water supply from hydraulic fracking. Drilling requires significant amounts of water to create a circulating mud that cools the bit and carries the rock cuttings out of the borehole. After drilling, the shale formation is then stimulated by hydraulic fracking, using up to 3 million gallons of water.
Data needs to be gathered on the impact to water resources of supplying water for the construction of thousands of wells per year. For gas to flow out of the shale, nearly all of the water injected into the well during fracking must be recovered and disposed of. Though less than 0.5% by volume, the proprietary chemicals are 15,000 gallons in the waste from the typical 3 million gallon hydro fracking job. The chemicals serve to increases the viscosity of the water to a gel-like consistency so that it can carry the propping agent (typically sand) into the fractures to hold them open so that the gas can flow. Determining the proper methods for the safe disposal of the large quantities of this fracking fluid that may also contain contaminants from the geological formation including brines, heavy metals, radionuclides and organic contaminants and monitoring the impact from this disposal must also be done. The impact of so much waste water on our water resources must be measured and monitored. In a study that was published in the Bulletin of the Seismological Society of America, concluded that the fracking did not cause the earthquakes, but there seemed to be a relationship to the deep well injection of the fracking fluid to small earthquakes experienced in Texas. The water caused the earthquakes Finally, care must be taken to avoid degradation of watersheds and streams from the industry itself as large quantities of heavy equipment and supplies are moved on rural roads and placed on concrete pads. The watersheds must be monitored.
http://pubs.cas.psu.edu/FreePubs/pdfs/XH0010.pdf
The U.S. success in gas recovery has set off shale gas explorations worldwide, and promising sites have been uncovered in Europe, particularly in France, Germany, Poland, and Ireland. Where there was coal there is shale gas. And as France's environment minister Nathalie Kosciusko-Morizet pointed out, gas is gas. When it burns, natural gas emits the lowest amount of carbon dioxide per calorie of any fossil fuel and burns cleanly because of this natural gas could be the “bridge fuel” in the long-term transition away from fossil fuels to renewable energy or whatever the future and science will discover. However, The U.S. Environmental Protection Agency (EPA) has said that loose pipe fittings and intentional venting for safety purposes on natural gas lines are a significant source of greenhouse gas emissions. (If you recall, methane and water are significant greenhouse gases.) These releases should be measured and the spurious emissions eliminated or at least significantly reduced. The environmental costs of sloppy production techniques and short cuts should be fresh in our minds after the Gulf of Mexico disaster, but the Deepwater Horizon fades from memory much too quickly.
In the 1990’s natural gas, sold for $2 per million BTUs after peaking in 2005 natural gas is now about $4 per million BTUs, making the extraction of shale gas viable and profitable. The U.S. uses natural gas to produce 21 % of its electricity. Coal is used to product 48 % of electricity in the United States and is still much cheaper than natural gas for generating electricity, but new regulations by the EPA on carbon emissions could decrease that financial advantage because coal burns dirtier than natural gas. Recent ambitious plans to convert the nation to renewable energy: build nuclear plants and solar and wind farms, were made under the assumption that natural gas prices would average $7 to $9 per million BTUs. At that level, electricity prices would have been high enough to make wind and nuclear power look affordable. Now, with natural gas at $4 per million BTUs and more gas reserves announced each year, many of these projects suddenly look too expensive. Shale sourced natural gas could profoundly change the future of our nation and world we live in; however we need to remember that the gas still is a limited resource and be cautious about what other impacts fracking might have on our other resources especially the hydraulic balance.
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