The fuel of civilization is usually found in unattractive places. Geologists discovered the biggest oil and natural gas reserves in the deserts of the Middle East and beneath the permafrost of Siberia. Countries in temperate Central Europe, on the other hand, have only modest reserves. One of them lies some 5,000 meters (16,000 feet) beneath the surface in Rotenburg/Wümme, an administrative district in the northwestern German state of Lower Saxony.
The most recent well that was drilled into the natural gas field there is called "Bötersen Z11." The site, located next to a federal highway near the port city of Bremen, occupies about a hectare (2.5 acres) of asphalt-covered land surrounded by a green wire fence. A pipe about as thick as a tree trunk is protruding from the middle of the site, but nothing is coming out of it.
There isn't enough pressure in the field the pipe is sticking out of, and ExxonMobil, which operates the well, isn't surprised. Even during the planning stages, "Bötersen Z11" was a candidate for a process that engineering geologists refer to as "induced hydraulic fracturing," or "fracking" for short.
ExxonMobil plans to inject about 350,000 liters (92,500 gallons) of water, mixed with a cocktail of chemicals, into the well under high pressure. The liquid is supposed to penetrate into the rock at the bottom of the pipe and trigger a long-term loosening effect. Hair-line fractures will create a network of tiny channels from which natural gas can escape for at least 15 years, according to ExxonMobil estimates.
But what ExxonMobil still lacks is official permission to do this. The state mining agency has been sitting on the company's application for the last year, hesitant to move forward with its approval.
"Unfortunately, fracking has become a scary word," says Dieter Sieber, a mining engineer and fracking expert at ExxonMobil. A cart decorated with pamphlets from a local citizens' initiative is parked at the entrance to the drilling site. The group aims to "protect God's creation," and one of its signs proclaims: "Stop Fracking!"
The public reservations and protests are coming at a surprisingly late point. As a method to increase the yields of hydrocarbon deposits, fracking has been in use for almost 50 years. In Germany, it has been instrumental in preventing domestic natural gas production from drying up altogether. Very few Germans are aware that, until the 1980s, almost a quarter of the natural gas being burned in Germany came from domestic sources. Although it's still about 12 percent today, that number is declining by about 1 percent a year.
The deposits that have already been discovered are almost exhausted. About 300 wells have been fracked in Germany since the 1960s. Without imports, more than three-quarters of which come from Russia, Norway and the Netherlands, Germany would soon find itself without natural gas -- if there weren't another alternative, that is.
In May, Germany's Federal Institute for Geosciences and Natural Resources (BGR) published a study concluding that there are up to 2.3 trillion cubic meters (81 trillion cubic feet) of technically recoverable natural gas under German soil, primarily in the northern state of Lower Saxony and the western state of North Rhine-Westphalia. This would be amount to more than 20 times Germany's annual consumption of natural gas.
The reserves are in deposits that are described as "unconventional," consisting of shale and coal formations, which are the primary "source rocks" of hydrocarbons. They were long considered unexploitable because they are substantially denser than "conventional" deposits found in more porous sandstone. The coveted fuel simply doesn't flow out of shale formations -- which is where fracking comes in.
Fracking is now proving to be a key technology for extracting oil and gas from shale formations. In Germany, the natural gas reserves that could be exploited in this manner would have "the potential to make up for declines in production in recent years," explains geophysicist Dieter Franke, a geophysicist who heads the BGR's oil and gas geology department. In light of the sheer magnitude of proven reserves, this could be seen as a conservative estimate.
Since the mid-1990s, Americans have been far more aggressive and active when it comes to fracking. Geologists estimate that -- after China and, presumably, Russia -- the United States has the third-largest shale natural gas reserves on Earth, or about 20 times as much as Germany. The United States is exploiting these reserves on a large scale and even hopes to use fracking to end its dependence on gas imports.
Now the United States is also taking a similar approach with shale oil. Thanks to fracking, the Midwestern state of North Dakota already produces more than half a million barrels of oil from the Bakken shale formation. As a result, this year, the state surpassed Alaska in oil production for the first time. According to a forecast by the Organization of the Petroleum Exporting Countries (OPEC), oil-tanker traffic to North America could very well be eliminated by 2035.
Hesitant about a Promising Technique
The BGR is also investigating Germany's oil shale reserves and expects to have results within three years. Geophysicist Franke anticipates that the study will reveal "significant quantities of exploitable reserves."
But whether this oil will ever be extracted remains uncertain. Even the natural gas that has already been found is still a long way from flowing out of wells. In contrast to the United States, which once met its own oil requirements and is now enthusiastic about returning to this status, government agencies in Europe are tentative.
France, which is assumed to have the largest unconventional gas reserves in Western Europe, has yet to issue a single fracking permit. German authorities have only permitted isolated test fracking. ExxonMobil, for example, was only allowed to conduct three experimental fracking operations in February 2008 at the "Damme 3" well north of Osnabrück, in northwestern Germany. Close to 13,000 cubic meters of fluid were injected into the wells. "We demonstrated there that fracking can be done in shale rock, and that the expansion (of the fracking fluid) corresponds to the simulations," says Sieber, the ExxonMobil engineer.
Although it has provided this insight, "Damme 3" has yet to generate any profits. To be able to make money from extracting gas from the well, ExxonMobil would have to inject more fracking fluid into the formations that contain natural gas -- but it hasn't been granted the permits to do so. The last fracking operation in German bedrock was conducted in late July 2011 -- also by ExxonMobil -- at the "Buchhorst T12" site, a conventional gas deposit in Bundsandstein, a type of colored sandstone that lies below large parts of Western and Central Europe.
Fears and Frustrations
Horror stories from the United States, an El Dorado for companies engaged in fracking, have discredited the technology. A documentary film about the practice showed a fireball emerging from a faucet, a result of the presence of methane in drinking water. Although it was never proven that fracking is responsible for such incidents, they have made the public afraid of the practice. People are starting to realize that pumping 13 million liters of chemical-laced water into a hole can have unpleasant consequences.
What happens in the bowels of the Earth when the hydraulic stimulator fractures the rock? Can natural gas, fracking fluid or formation water containing hazardous substances seep into and contaminate the groundwater?
These are extremely urgent questions, and it's astonishing that we are only now beginning to systematically search for answers. In early September, Germany's Federal Environment Agency (UBA) published an initial report with a sobering conclusion: "In summary, we conclude that a great deal of the fundamental information needed to make a valid assessment of these risks is still missing."
For regulators, who must ultimately decide whether fracking should be allowed, such a conclusion is as unhelpful as it is for the oil companies that want to use the fracking technology.
ExxonMobil, the leading natural gas producer in Germany, is paving its way to unconventional deposits with slick PR efforts. The company is already running TV ads in which its managers insist that they are also concerned about clean drinking water. ExxonMobil has also set up a website called Erdgassuche-in-deutschland.de, or "The Search for Natural Gas in Germany," to emphasize its transparency. The site even lists the ingredients in the last fracking cocktail used at the "Buchhorst T12" well.
Occupational medicine experts have classified substances like tetraethylenepentamine as being toxic to groundwater and corrosive. ExxonMobil points out that the concentrations of such chemicals in fracking fluid are very low. "If you were to drink more than three or four glasses of fracking fluid," says Sieber, "the worst that would happen to you would be the sort of diarrhea you'd get from drinking castor oil."
Studying and Waiting
But it's millions of liters of fracking fluid -- and not just three or four glasses -- that are injected into a well. And the government agency with the power to approve or prohibit the practice isn't the Environment Ministry, but rather the mining authority in each of Germany's 16 federal states. For Lower Saxony, where Germany's most promising candidates for fracking are located, it's the State Authority for Mining, Energy and Geology (LBEG), based in Hanover.
Ulrich Windhaus heads the agency's permit-granting department. "We have taken a very careful look at the situation with fracking," he explains, "and not just since the most recent debates." The unique problem in Germany, Windhaus adds, is that the shale formations containing the gas are closer to the surface than most conventional deposits, which means they are much closer to groundwater levels and, in some cases, even within the same stratum. Some shale formations in Lower Saxony reach almost to the surface. For this reason alone, says Windhaus, "a more comprehensive analysis has to be conducted."
ExxonMobil doesn't disagree. Like the agency, the company also advocates careful exploration of the shale formations. But it doesn't at all like the general ban on fracking, which also applies to reserves in conventional deposits. "ExxonMobil has already conducted more than 180 fracking operations in Germany," Sieber asserts, "and in not a single case has it contaminated the environment or drinking water."
The engineer feels that he is being put in a straitjacket in the struggle over the fracking license for the "Bötersen Z11" well. "The well site is sealed and the well is secured by several barriers consisting of steel pipes and layers of cement," he says. Besides, he adds, the deposit is kilometers below the strata containing groundwater.
Nevertheless, the state agency is still refusing to hand out permits. "The documents that were submitted are incomplete," says Windhaus. He is referring, among other things, to a hydrogeological report that ExxonMobil says is more complex than any such reports requested in the past.
Sieber is standing at the drilling site, which resembles a huge, empty parking lot, looking at the cart in the adjacent field plastered with protester posters. ExxonMobil has invested about €20 million ($26 million) in Bötersen Z11. If it doesn't get its fracking license, it will be a wasted investment.
It's certainly not the kind of money that could put a serious dent into an oil company's profits, and Sieber doesn't want to focus on the investment as an argument. "According to our estimates," he says, "the well could produce 500 million cubic meters of natural gas, or enough to supply 250,000 households with energy for one year."
Now that number, says the ExxonMobil engineer, sounds a lot better.