Some industry veterans believe it's the biggest development in the energy game since 1859, when the first US oil well gushed from beneath the earth in Titusville, Pennsylvania.

In changes that would have been unthinkable just five years ago, the US is set to become a net energy exporter in the next few years, thanks to the controversial process of fracking that is re-wiring geopolitics and the world of energy.

The practice of shooting steam and chemicals into shale rock formations to unlock energy sources previously considered marginal has "changed the world", according to one lawyer with more than 40 years of experience negotiating natural gas contracts.

"We are talking about increases [in natural gas production] of 15 to 20 percent per year," George Washington University law professor Richard Pierce told Al Jazeera. "The US is now 100 percent independent in natural gas and within the next half a dozen years [North America] will be independent in oil. It will become a global supplier, rather than a demander, in a hurry."

'Once-in-a-lifetime experience'

New technologies to access hard-to-reach fuels mean that, in 2012, the United States experienced its largest rise in annual oil output since the middle of the 19th century, according to data from the US Energy Information Administration (EIA) released in December. Shale gas is a fossil fuel trapped inside formations of shale rock. Some of these formations also contain oil.

US crude oil production is also rising, with production hitting 7.5 million barrels per day in July, the highest level in more than 20 years according to the US Energy Department.

Monthly crude oil production will exceed US crude oil imports by October, the EIA reported in August.

"This is a once in a lifetime thing we are experiencing now," Paul Faeth, a senior fellow with the CNA research organisation, told Al Jazeera. "The chemical industry is moving back to the US [because of cheap gas] and demand will increase because of low prices."

The gas boom has led to about $90bn in new investments in related US industries over the past two years, including steel manufacturing, petrochemicals production and fertiliser fabrication, according to Dow Chemical's calculations.

Between 2005 and 2012, more than $125bn was spent on shale extraction, including drilling and purchasing land, by the 50 largest US oil and gas companies, according to a study by Ernst and Young.

High prices over the past decade, the flow of petroleum from east to west, and the gush of money the other way has allowed Russia to re-assert its international clout and Gulf states to build up massive sovereign wealth funds. The shale boom has the potential to derail those trends.

In 2011, members of the Organisation of Petroleum Exporting countries (OPEC) earned $1,026bn in net oil export revenue, a 33 percent increase over 2010, the US Energy Information Adminisiration reported in May 2012. If the price of oil drops because of new supplies, or if natural gas starts to eat into demand for traditional crude, oil-rich nations could potentially find themselves significantly less well-off.



"There will be significant impacts for security and global politics," Faeth said of the shale boom.

Blue-eyed 'sheikhs'

Thanks largely to fracking, the US is set to overtake Saudi Arabia and Russia to become the world's biggest oil producer by 2017, according to a November 2012 report from the International Energy Agency (IEA).

Should gas-dependent leaders, including Russia's Vladimir Putin or the Emir of Qatar, be worried? Will the wealth and power of steely-eyed ex-KGB agents or white-robed sheikhs be overshadowed by a rebirth of the American oil man - a new breed of Beverly Hillbilly?

"In the medium term, I think Qatar and Russia are okay," Frank Asche, professor of risk management at the University of Stavanger in Norway, told Al Jazeera. "Not [just] because they sell to customers on long-term contracts, but because the infrastructure is there."

Transporting natural gas around the world is more difficult than moving oil. Russia has pipelines running to Western Europe, while Qatar - the world's largest natural gas exporter - has shipping terminals in key Asian markets.

There is no question that fresh water is going to be a serious concern… the water crisis will be the next big crisis people will have to confront everywhere in the world in the next few decades Richard Pierce, George Washington University law professor

Oil has a single, global price. But because of transportation challenges, the cost of natural gas varies widely between markets: Japan pays more than five times as much for natural gas compared with the US, according to some estimates. But that could change as new reserves are found and technologies advance.

"I think we are moving closer to a global natural gas market," Asche said. "It's only a matter of time, I think, until you see something like a big super-tanker that can carry LNG (liquefied natural gas) around the world."

In the short-term, when prices are dependent on geography, the US is hardly alone in tapping into shale formations for domestic consumption. Other states that traditionally imported much of their gas, including Australia, Argentina, South Africa, Poland and China are also looking to cash in on the shale boom. But for now, the US is benefiting the most from the recent gas gush.

Environmentalists and some analysts, however, caution that jubilant predictions from a country that consumes some 25 percent of the world's oil will run into environmental constraints including global warming and a lack of fresh water.

"There is no question that fresh water is going to be a serious concern… the water crisis will be the next big crisis people will have to confront everywhere in the world in the next few decades," Pierce, the energy lawyer and professor, said. "Limits on fresh water, to a certain extent, will be the determining limit on fracking capability… how serious a limit is hard to say."

Environmental impacts

Extracting gas from one well through fracking takes about five million gallons of water, the equivalent of between 800 and 1,300 truckloads, said energy consultant Faeth. Over its lifespan, an average well produces more than 4 billion cubic feet of gas equivilent - enough energy to power about 16,000,000 homes for one day. Mixed with chemicals, much of the water ends up contaminated after being used in the fracking process. One well will often need to be fracked up to 18 times, drastically increasing water contamination.

"The industry is not that transparent; we don't know exactly how much water is being used in different places," Lorne Stockman, research director of advocacy group Oil Change International, told Al Jazeera. "Public discomfort with the fracking boom is growing, especially in states like Ohio… I can't say if it will come to a head."

Despite concerns about water quality, energy companies and supporters of unconventional gas extraction say the process is good for the environment, as it means "dirty" coal could be replaced by gas in power plants and other facilities.

The jury is still out on whether that's correct.

A study released in the journal Nature earlier this month found that fracking operations in Utah and Colorado leak about nine percent of the total methane contained in the wells. Methane, the chief component of natural gas, is a far worse contributor to global warming compared with carbon dioxide, and the figure of nine percent claimed by the study is higher than previously thought.

"The methane emissions matter a lot in the broader scheme of things," Faeth said. "If the study is right, the impacts of unconventional gas [on the climate] would not be positive compared to coal… [For environmental problems] gas will not be the long-term solution."

The fracking process, which forces steam and chemcials into rock formations, has also been known to cause earthquakes in Ohio, the UK and other regions.

'Leave it in the ground'

The gas boom could actually hurt sustainability in the long-term, as investment capital needed to finance research into solar, geothermal and wind energy is diverted to drill for gas in middle America.

Many experts worry about the environmental impacts of fracking to access new energy supplies [Al Jazeera]

If natural gas prices remain reasonably stable, banks can get a guaranteed return on capital invested in extraction, making the shale game a reasonably safe bet that is popular with Wall Street. New, renewable technologies, on the other hand, often take years of research before they come to market and a return on investment is not guaranteed. Often pioneered by small start-ups, the next energy game-changer could miss out on funding opporunities, as the big players are busy tapping shale deposits.

In some respects, the industry has been a victim of its own success in the short-term; natural gas prices in some areas are down more than 50 percent since the middle of 2008, due to new supplies coming into the market. "In the power sector, cheap gas has hurt renewables to some degree," Faeth said.

Traders in New York and wildcat drillers in Pennsylvania might be celebrating the newly minted resources, as are security hawks who relish the idea of reducing US energy dependency on the Middle East.

But there is near-universal consensus among scientists and policymakers that these new resources should be left in the ground.

"No more than one-third of proven fossil fuels can be consumed prior to 2050 if the world is to achieve the two degrees Celsius goal" - the limit for averting catastrophic climate change - according to International Energy Agency data released in November. The IEA is hardly Greenpeace, and predictions from the IEA, an industry-backed body, should be taken seriously, environmentalist campaigners said.

Leaving massive amounts of cheap natural gas untouched, however, will be nearly impossible for politicians in the US and beyond who are keen to jumpstart recession-battered economies and end dependence on foreign energy sources.

"The advantages gained geopolitically [for the US] by these new sources are small compared to the disadvantages of remaining dependent on oil as a source of energy given the threat of climate change," Stockman said.

"You can't separate climate change from discussions about global security. We have far more oil, gas and coal than we can afford to burn if we are going to avoid catastrophic climate change."

Follow Chris Arsenault on Twitter: @AJEchris