By Alex Kimani of OilPrice.com
The U.S. shale revolution dramatically reshaped the world energy markets. The shale boom was one of the most impressive growth stories, from take off in 2008 to the Permian stealing the mantle from Saudi Arabia’s Ghawar as the world’s highest producing oilfield in a little over a decade. Overall, Reuters has estimated that, “U.S. petroleum production is at least 10-11 million bpd higher than it would have been without horizontal drilling and hydraulic fracturing.’’
Unfortunately, the shale patch has lately been struggling to ramp up production due to a litany of challenges including pressure from investors to boost returns, limited equipment and workers as well as a lack of capital.
But shale giant ExxonMobil is now betting that shale producers can double crude output from their existing wells by employing novel fracking technologies.
“There’s just a lot of oil being left in the ground. Fracking’s been around for a really long time, but the science of fracking is not well understood,” Exxon Chief Executive Officer Darren Woods said Thursday at the Bernstein Strategic Decisions conference. Woods has revealed that Exxon is currently working on two specific areas to improve fracking. First off, the company is trying to frack more precisely along the well so that more oil-soaked rock gets drained. It’s also looking for ways to keep the fracked cracks open longer so as to boost the flow of oil.
Luckily, the U.S. Shale Patch won’t have to wait for Exxon to perfect its new fracking technologies. There's already a proven technology for oil producers to return to existing wells and give them a second, high-pressure blast to increase output for a fraction of the cost of finishing a new well: shale well refracturing.
Refracturing is an operation designed to restimulate a well after an initial period of production, and can restore well productivity to near original or even higher rates of production as well as extend the productive life of a well. Re-fracking can be something of a booster shot for producers--a quick increase in output for a fraction of the cost of developing a new well.
While refracturing has never really gone mainstream, the technique is seeing higher adoption as drilling technology improves, aging oilfields erode output, and companies try to do more with less. According to a report published in the Journal of Petroleum Technology, new research from the Eagle Ford Shale in south Texas shows that refractured wells using liners are even capable of outperforming new wells despite the latter benefiting from more modern completion designs.
JPT also estimates that North Dakota’s Bakken Shale straddles some 400 openhole wells capable of generating an excess of $2 billion if refractured. Mind you, that estimate is derived from oil prices at $60/bbl vs. this year’s average oil price of almost $90/bbl. According to Garrett Fowler, chief operating officer for ResFrac, a refrac can be up to 40% cheaper than a new well and double or triple oil flows from aging wells.
How Refracs Work
Fowler says the most common re-frac method involves placing a steel liner inside the original well bore and then blasting holes through the steel casing to access the reservoir. The process typically uses half as much steel and frac sand than a new well
Refrac makes a lot of sense in the current inflationary environment. Back in April, Texas shale producer Callon Petroleum Company (NYSE: CPE) revealed that frac sand, drill pipe and labor costs have increased drilling and well-completion service costs ~20% Y/Y. Callon and Hess Corp. (NYSE: HES), both of which drill in North Dakota's Bakken shale, have been forced to hike capital spending budgets over the costs with Callon adding $75 million to its original budget while Hess added $200 million to its spending,
"Techniques like re-fracturing will allow the industry to continue to harvest the oil and gas out of these reservoirs," said Stephen Ingram, a regional vice president at hydraulic fracturing firm Halliburton Company (NYSE: HAL).
Another key benefit: re-fracs do not require additional state permits or new negotiations with landowners. They are also less disruptive to the environment because well sites already have road access.
"Considering inflation, supply chain issues, and rising wages, now is a great time for operators to start looking at wells for re-frac opportunities," Matt Johnson, CEO of energy consultancy Primary Vision Network, has told Reuters.
Refracs have also demonstrated higher recovery rates: in URTeC 3724057, Roberta Barba, a longtime completions consultant and CEO of Houston-based Integrated Energy Services, et al. share a case study from the Eagle Ford Shale in south Texas involving five refractured wells. The refractured wells had a combined average post-refrac EUR of 13.2% compared to an initial EUR of 7.4% average by seven new infill wells with modern completion designs.
Robert Barba, a longtime completions consultant and CEO of Houston-based Integrated Energy Services (IES).Estimated ultimate recovery (EUR) refers to potential production expected from an oil well or deposit and is made up of three components: proven reserves; probable reserves; and possible reserves.
The Authors of the paper say that despite the presumed advantages of a modern completion, refracs can increase stimulated reservoir volume “beyond what is achievable in a new completion”. This is attributed to the fact that as the reservoir depletes and pore pressure drops, fractures from a refrac tend to grow into a new direction and tap previously inaccessible portions of rock.
Despite these seemingly clear benefits, it's surprising that refrac remains a fringe tech in the U.S. Shale Patch. Norwegian energy consultancy Rystad Energy has estimated that out of all the U.S. horizontal well stimulations performed through September, out of the 8,900 total stimulations from January to September, only 200, or a little over 2%, were refractured wells. The vast majority were in the Permian Basin spanning Texas and New Mexico and involved wells drilled before 2018. Rystad estimates that the count will rise to ~400 refracs by year’s end, or a little over 3% of total completions and comparable to last year’s final tally of 409 refracs.
“It’s a very niche market. The companies that are doing it are probably going to continue to do it, but I don’t think refracs are going to explode in numbers next year. I see stable activity that is very similar to this year’s 2–3% of total completions,” Justin Mayorga, a senior analyst of shale research for Rystad, has told the Journal of Petroleum Technology.
Indeed, Rystad says many U.S. shale producers use refracs more to protect the outcomes on new child wells that share the same pad rather than to boost production from older wells. It’s not for lack of opportunity though: in the Permian Basin alone, Alfredo Sanchez, CEO of oil field equipment supplier MorphPackers, estimates that there are tens of thousands of wells that are good candidates for refracking.
Nevertheless, Barba is optimistic that the U.S. Shale Patch will shift toward higher rates of refracturing in the not-too-distant future for one key reason:
“We are seeing higher recovery factors on refracs--cumulative oil plus the estimated ultimate recovery (EUR) of the refrac--than we are in new wells.”