Call it hydraulic fracturing — without the hydro.
In most hydraulic fracturing operations, several million gallons of water, together with sand and chemicals, get pumped down a hole to blast apart rock that encases oil or gas. But with water increasingly scarce and expensive around Texas, a few companies have begun fracking with propane or other alternatives.
“We don’t use any water,” said Eric Tudor, a Houston-based official with GasFrac, a Canadian company that fracks with propane gel and butane. “Zip. None.” At a GasFrac operation in South Texas last month, a sticker on one worker's hard hat showed a red slash through the word H2O.
Water-free fracking still remains an early-stage technology, with potentially higher initial costs than conventional fracking methods. But as lawmakers and oil regulators focus on the large quantity of water used for fracking wells, the concept is getting a closer look. GasFrac has led the way, bringing its propane fracking operations to Texas, and there is talk of using other substances like carbon dioxide or nitrogen.
"We've looked at [propane fracking], and I would say that absolutely our industry is open to all possibilities," Michael Dunkel, the director of sustainable development for Pioneer Natural Resources, said in testimony last month before a joint hearing of the House Energy Resources and Natural Resources committees.
Waterless fracking is “a viable technology for sure,” said David Yoxtheimer, an extension associate with the Marcellus Center for Outreach & Research at Penn State University. However, he noted, there is a reason that companies use water, namely that it is "virtually incompressible" and thus is very effective in bringing pressure against, and ultimately breaking up, rock.
Currently there are no special rules on fracking with propane or other nonwater liquids in Texas, according to Christi Craddick, one of three members of the Railroad Commission of Texas, which regulates the oil and gas industry. The technology is “exciting” but still rare, she said, and no rule changes are on the horizon.
“We’ll see as the technology evolves if our rules need to evolve,” Craddick said last week in an interview.
Tudor, of GasFrac, said his company began working in Texas in 2010, after fracking its first well in Canada in 2008. It has done roughly 100 fracks in Texas so far, he estimated. (Some wells get fracked multiple times.) Much of the work has been in South Texas. A recent job bored into the San Miguel formation, which is a relatively shallow formation in the vicinity of the Eagle Ford Shale. But GasFrac has also done “a couple of prototype fracks” in West Texas, he said.
“We're just getting started," Tudor said.
Academics see a number of challenges associated with propane fracking, which few if any companies are experimenting with in Texas, apart from GasFrac. First, according to Yoxtheimer, “you’ve got to truck in a lot of propane,” which can be expensive. He also said the propane “works less effectively in deeper formations where you need to build up more pressure.”
Tudor disagrees that these issues pose problems. He pointed out that the virtually all the propane — which is a byproduct of natural gas processing and oil refining — gets reused. Supplies of propane come from Corpus Christi, he said, and the fuel is "easily available" in South Texas. "We won't cause any shortages," he said.
That is an implicit contrast with the considerable water needs of conventional fracking, which already accounts for a double-digit percentage of water use in some rural Texas counties. The water leftover from fracking operations typically does not get reused. Instead, it gets discarded into a disposal well. (The Texas Railroad Commission on Tuesday approved rules to make it easier for companies to recycle water.)
Tudor also said that his company had fracked at depths well over 10,000 feet.
An advantage of propane fracks, said Yoxtheimer, is that they avoid the damage to the oil and gas-producing formation that water can cause.
“If you’re using water, the water can actually block off or at least impede the flow of hydrocarbons,” he said.
Tudor agreed, saying that his company could recover a higher percentage of the oil or gas with propane than with a traditional water frack job. It was this increased production, rather than the reduced use of water, that enticed GasFrac's customers, he said.
David Burnett, research coordinator at the Department of Petroleum Engineering at Texas A&M University, said that more study is needed. Evidence that the wells fracked with propane are more productive is “sort of anecdotal data,” he said.
As for the risks of handling flammable material like propane, “Our industry is used to handling high-pressure gas and pumping flammable liquids,” Burnett said. “It’s not an issue if the equipment is designed properly.” The risks, he added, are “no more worrisome than a propane tank on the edge of town.”
Tudor said that his company had done 2,000 or more fracks by now, with only one “minor incident in Canada” in which a worker got blisters while some equipment was being shut off. Any leaks, Tuder said, can be “quarantine[d], and “we’re always hooked up to a flare” that can release the gas if needed. The company uses thermal cameras to monitor “hot areas” remotely.
As GasFrac’s technology spreads, other companies are also trying to use less water. In testimony last month before the joint hearing of the House Natural Resources and House Energy Resources committees, Glenn Gesoff, an official with BP who also chairs the water committee of the Texas Oil and Gas Association, told lawmakers that there were "a number of tests going on" in waterless fracking and fracking that uses significantly less water. In addition to propane, he said, work is ongoing with carbon dioxide and nitrogen.
"They're in the development phase," Gesoff said. "There are some safety concerns."
Marathon Oil has begun using a new formula, which it describes as a “guar mix commonly used in ice cream and other food products,” to reduce its water use. Guar is a small bean that can thicken water, and the thicker fluid can carry the sand and other elements “while simultaneously using less water,” Lee Warren, a Marathon Oil spokesman, said in an email.
Over the last 18 months, she said, Marathon has cut its water use by 45 percent per well.