As shale gas plays mature and production data are collected, analyzed and published by public and private analysts, the evidence is clear that despite industry’s best efforts, a large portion of the gas originally in place could remain unproduced unless the percentage of technically recoverable gas is increased.

Efforts to quantify recovery performance have begun for some of the more mature plays. For example, the University of Texas’ Bureau of Economic Geology’s comprehensive assessment of the Barnett Shale play published in 2013 puts the total for technically recoverable gas from the entire play at 2.4 Tcm of 12.6 Tcm (86 Tcf of 444 Tcf) in place, or 19.4%. The volume projected to be produced under the economic assumptions of the study is even lower. Other approaches have been employed to estimate ultimately recoverable gas volumes for the major shale gas plays, with some results averaging only 5.4%. So there appears to be plenty of room for improvement when one compares these recoveries with recoveries typical of “conventional” reservoirs (up to 80%). Improving recovery from shale gas plays is one of the major challenges we face in maximizing the potential national economic and environmental benefits of this resource.

While the geological differences between shales and conventional gas reservoir rocks may limit how close we can get to historical recoveries, producers have made enormous strides in increasing per-well EURs by lengthening horizontal laterals, increasing the number of fracturing stages and adjusting proppant concentrations. More work remains to be done if the full potential of the U.S. shale gas resource is to be realized.

Part of the mission of the U.S. Department of Energy’s (DOE) National Energy Technology Laboratory (NETL) is to accelerate the development of technologies that can maximize recovery of the nation’s oil and natural gas resources while minimizing environmental impacts. Since 2007, NETL has funded 30 individual research projects focused on improving our understanding of how gas is produced from shales and tight sandstones and how hydraulic fracturing influences production. These projects, many of which were implemented through partnerships between research universities and producers, were carried out under the Ultra-Deepwater and Unconventional Natural Gas and Other Petroleum Resources Research Program launched in 2007 by the Energy Policy Act of 2005. Although this program ended in 2014, work on already funded projects will continue through September 2016.

Earlier this summer, through traditional appropriations, NETL continued to build on this work by soliciting new research partners for work specifically focused on creating long-term research sites that could be used to monitor the nature of shale gas development and test technologies that have the promise to improve recovery efficiency and environmental performance. The sites will offer a unique opportunity to enable an open, collaborative and integrated program of science and technology development and testing.

In the 1980s a similar multiwell field laboratory in the Piceance Basin, the Multi-well Site funded by the DOE and the Gas Research Institute, was the scene of a wide range of experiments that provided important basic knowledge on how to maximize recovery from tight sandstone reservoirs. Hopefully, this new initiative will be equally successful in contributing useful findings over the long term.

The results of NETL’s completed and ongoing unconventional natural gas research can be found on the NETL website at netl.doe.gov/research/oil-and-gas/.

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