Successful 3-stage hydraulic stimulation of injection well 16A(78)-32

The Utah FORGE research team has achieved yet another major milestone in advancing enhanced geothermal system technologies with the successful completion of the first large scale 10-day stimulation trial (April 14-24, 2022) in the deep deviated well 16A(78)-32. Three intervals were tested in sequence at greater than 10,000 ft depth, including the open hole at the toe of the well (Stage I), followed by two shallower 20 ft intervals that were lined with solid casing (Stages 2 and 3). In each stage, between 3000 and 4000 barrels of water were injected under pressure, causing pre-existing fractures in the reservoir to dilate and transfer heat to the injected cold water. After a 4-hour shut in, the hot injected water was produced back to the surface under controlled flow conditions. The stimulation trial ran according to schedule and plan, including the seamless deployment and retrieval of the bridge plugs at high pressures and temperature.

The ability to initiate, propagate and ideally control hydraulic fracture growth is essential for realistically evaluating the potential for commercial EGS applications. Success here is important for promoting technical and hybrid EGS methods that use hydraulic injection to provide a heat exchange network or to achieve more effective connections with potentially productive natural fractures.

In late 2022 or early 2023, a second deep deviated well, the production well, will be drilled to intersect the hydraulic fractures. The connectivity of the fractures between the two wells will be established or improved, and short-term circulation testing will begin to assess the thermal viability geothermal reservoir.

Utah FORGE wraps up a 3-stage hydraulic stimulation of well 16A(78)-32

Utah FORGE is excited to announce the successful completion of the three-stage hydraulic stimulation of its first highly deviated injection well, 16A(78)-32.

Well 16A(78)-32 drilling was completed in January 2021. This is an inclined well (65°to the vertical) that will be the injection arm of the doublet that forms the heart of the Utah FORGE experimental configuration.

Subsequently, two additional monitoring wells – vertical – were drilled so that they, along with existing well 58-32, could serve as monitoring wells for future work at the FORGE site. In particular, wells 58-32, 78B-32 and 56-32 had been instrumented with fiber optics and geophones to triangulate on microseismic events during the recent fracturing in Well 16A(78)-32. These microseismic clouds define the morphology of three hydraulic fractures created at the toe (extremity) of Well 16A(78)-32.

A chronology of the events for the recent three-stage hydraulic fracturing is as follows:

  • Fourteen frac tanks were sited on the location and filled with Milford City culinary water. Each tank holds 500 bbl (21,000 gallons per tank) of water.
  • Frontier Drilling Rig 28 was trucked to the location, assembled, and brought into service.
  • A preliminary run of drill pipe was made into the hole. This drill string had a bit with a casing scraper and a drift sub. The bit was run to near the end of the open-hole section of the wellbore while the casing scraper was positioned to stay within the cased-hole and ensured the absence of debris. The drift sub was run one joint above the casing scraper and guaranteed that there was adequate clearance to run additional tools (in particular, bridge plugs).
  • Extreme Wireline next ran a perforating gun on the end of drill pipe into the openhole section (below 10,787 ft MD). In addition to the perforating gun, a mechanical casing collar locator was run and confirmed the casing tally so that the depth of the gun was more accurately known. This 3-1/8” diameter gun was 2 ft long with 6 shots per foot at 60° phasing. MTS Solutions pumped down the drill pipe to seat a dropped ball and fire the guns. The successful firing served as a check shot for orienting geophones in the three offset wells.
  • MTS Solutions next pumped a Shear Stimulation Test for one hour at an average rate of 0.36 bpm followed by shutdown and monitoring the pressure decline for an hour. A total of 52 bbl of water was pumped for this test.

STAGE 1

  • Liberty Oilfield Services next pumped down the casing and followed the prescribed fracturing plan for stimulation Stage 1, reaching an injection rate of 50 bpm with slickwater (refer to Figure 1). 4,261 bbl were pumped. The well was shut in for four hours and flowed back.
  • After 16 hours of flowback, Interwell US ran a bridge plug to a depth of 10,670 ft MD (middle of the sealing element). MTS Solutions pumped to set the bridge plug. The bridge plug was tested to 5,000 psi using MTS Solutions’ pumping equipment through the drill pipe and later to over 7,000 psi using Liberty Oilfield Services’ pumping equipment, down the casing.
  • After tripping the bridge plug setting tool out of the hole, an Extreme Wireline perforating gun was run into the hole on the end of drill pipe. This was a 20-ft long perforating gun (6 shots per ft, 60° phasing, 21-gram Hero charges). It was run to cover a depth of 10,560 to 10,580 ft MD. MTS Solutions pumped a dropped ball to a seat to fire the guns. The guns were retrieved. All 120 shots had fired, providing an entry from the wellbore to the formation.

STAGE 2

  • Liberty Oilfield Services next pumped 2,777 bbl of slickwater down the casing and followed the prescribed fracturing plan, reaching an injection rate of 35 bpm. This was Stage 2. There was an intentional hard shutdown in the initial 5 bpm stage and also part way through the 35-bpm stage. The well was shut in and pressure decline was monitored for 4 hours. The well was then opened up and flowed back for 12 hours. The treatment data are shown in Figure 2.
  • After flowback, Interwell US ran a second bridge plug to a depth of 10,466 ft MD (center of the sealing element). MTS Solutions pumped to set the bridge plug. The bridge plug was pressure tested to 4,960 psi by MTS Solutions through the drill pipe and later to 6,800 psi using Liberty Oilfield Services pumping equipment, down the casing.
  • An Extreme Wireline perforating gun was next run on the end of drill pipe to cover a depth of 10,120 to 10,140 ft MD. This was a 20-ft long perforating gun (6 shots per ft, 60° phasing, 21-gram Hero charges). MTS Solutions pumped to seat a ball and fire the guns. The guns were retrieved. All 120 shots had fired, providing an entry from the wellbore to the formation.

STAGE 3

  • Liberty Oilfield Services next pumped down the casing for Stage 3 and followed the prescribed fracturing plan, reaching an injection rate of 35 bpm. A slickwater pad was pumped followed by a crosslinked CMHPG fluid with DEEPROP™ microproppant at planned concentrations of 0.5 to 0.75 ppa. The total pumped fluid volume was 3,016 bbl. The well was shut in and flowed back (for more than 15 hr). Refer to Figure 3.
  • During the shut-in time, the Liberty frac crew began to rig-down their equipment and demobilize.
  • The well was re-entered with drill pipe and an Interwell US retrieving tool to release and recover the second bridge plug that was set. The bridge plug was successfully released and recovered to the surface. After disconnecting and laying down the bridge plug the retrieving tool was run back into the well to recover the first bridge plug that was set. This plug was also successfully retrieved and laid down.
Figure 1. This is the treatment record for Stage 1. The green trace indicates, the pumping rate, reaching 50 bpm. The red trace is the surface treating pressure, exceeding 6,000 psi. This stage was pumped into the 200 ft long open hole section of the well.
Figure 2. This is the treatment record for Stage 2. The green trace indicates, the pumping rate, reaching 35 bpm. The red trace is the surface treating pressure, exceeding 7,000 psi. This stage was pumped into a cased and perforated zone (10,560 – 10,580 ft MD) section of the well. Note the hard shutdown (rate intentionally rapidly brought to zero) part way through the treatment.
Figure 3. This is the treatment record for Stage 3. The green trace indicates, the pumping rate, reaching 35 bpm. The red trace is the surface treating pressure, exceeding 7,000 psi. The other traces show microproppant concentration at the surface and at the perforations. This stage was pumped into a cased and perforated zone (10,120 – 10,140 ft MD) section of the well.

Following the recovery of the bridge plugs from the well, on April 23, 2022 the rig started rig-down operations and laying down drill pipe.

Geothermal Song Parody Contest Winners

Utah FORGE and Enel-sponsored Geothermal Music Parody Contest

In early 2022, the Utah FORGE team launched a pilot competition for middle school students in Mr. Zac Taylor's science classes in Milford High School.  This competition introduced students to the basics of geothermal energy in an engaging and fun way. Thanks to a generous contribution from Enel, the winning team received iPads and the runner up a gift certificate.

WINNERS: Tanumafili Aaitui, Maddox Smith, Carson Cheney, Christian Kelley

RUNNER UP: Nathan Costello

CONGRATULATIONS EVERYONE!

Prizes were awarded at the Milford City Council Meeting on April 19.


Winning team Carson, Christian, Maddox, and Tanu
Runner Up Nathan

To prepare for the competition, Mr. Taylor, was provided with lesson plans that include information on geothermal energy. These lesson plans meet the Utah State Science with Engineering Education Standards and are in line with the standards set forth in the Next Generation Science Standards. He also received other background information such as videos, podcasts, and fact sheets. Working in teams, his students submitted short music videos, replacing the lyrics of popular songs with their own lyrics incorporating geothermal terms. A classroom visit from Enel engineers provided real world application and insight into the general concepts taught in class and into geothermal energy specifically. Enel also hosted a guided field trip to the Cove Fort geothermal plant to provide students with an up-close look at how electricity is produced from geothermal energy.

Partner Spotlight – ENEL

Enel is a clean energy leader and innovator that’s electrifying the economy in North America with a mission to combat the climate crisis and build a low-carbon future. For over 20 years, Enel has advanced the economic, social and environmental benefits of clean electrification in the US and Canada. Enel provides a full spectrum of integrated energy services to help companies, cities and utilities reduce their carbon emissions and maximize the benefits of electrification through utility-scale renewable energy and storage, flexible energy resources, energy management, electric transportation and grid digitalization.

Through its Enel Green Power business line, Enel is a developer, long-term owner and operator of renewable energy plants across the US and Canada with a presence in 14 US states and one Canadian province. The company operates 64 plants with a managed capacity of over 7.6 GW powered by renewable wind, geothermal and solar energy. Enel operates the Cove Fort geothermal plant in Beaver County, Utah and is developing solar projects elsewhere in the state.

Cove Fort is the world’s first large-scale power generation facility to successfully combine geothermal with hydropower technology. Enel added a fully submersible downhole generator technology to a geothermal injection well, combining geothermal and hydroelectric power at one site. The cutting-edge generator used at Cove Fort captures the energy of the water flowing back into the earth to generate additional power, while also better controlling the flow of brine back into the ground. The downhole generator creates backpressure within the injection well that prevents two-phase flow and the associated vibration and potential for damage. The result is a first-of-its-kind innovation that can reduce operational and maintenance expenses, while also having the potential to generate additional revenues.

Enel Green Power invests in the sustainability of its host communities and identifies areas to create shared value with local partners. As part of its local engagement around Cove Fort, Enel has invested in STEM education programs through organizations including Beaver County 4H and Utah State University.

Enel partners with FORGE for geothermal-focused STEM education initiatives in Beaver County, using creative instructional methods like a song contest to engage students in the world of renewable energy. More initiatives as part of this partnership are in development.

Globally, Enel is the largest European utility by ordinary EBITDA, and is present in over 30 countries worldwide, producing energy with around 89 GW of installed capacity.  Enel’s renewables arm Enel Green Power is the world’s largest renewable private player, with around 50 GW of wind, solar, geothermal, and hydropower plants installed in Europe, the Americas, Africa, Asia, and Oceania. The company’s geothermal portfolio includes the oldest geothermal plant in the world, located in Italy.

Modeling and Simulation Forum #14 Recording

Utah FORGE Modeling & Simulation Forum #14


"2021 Utah FORGE modeling summary and 2022 look ahead"

Presented by: Rob Podgorney (Idaho National Laboratory)

January 19 2021 at 11 am MST

Look back at the modeling and simulation efforts completed in 2021.

Looking ahead into 2022.

This is the 14th forum of the series and is intended to have an open format to present modeling and simulation, both completed and planned, as well as activities being conducted by the Utah FORGE Team.

This webinar has been recorded and is available for viewing.

To follow along with the slides, the pdf of the presentation is available for download HERE

For previous forums and for the upcoming schedule check out the Modeling and Simulation FORUM page

SSA 2022 Annual Meeting

This following SSA session will be in person in Bellevue, Washington on 19-23 April 2022:

De-risking Deep Geothermal Projects: Geophysical Monitoring and Forecast Modeling Advances
Co-conveners: Federica Lanza, Kristine Pankow, Alexandros Savvaidis, Stefan Wiemer, Antonio Pio Rinaldi, Nori Nakata

We seek contributions from EGS projects and field test sites that focus on geophysical technologies applied to geothermal energy, such as real-time monitoring and characterization of induced seismicity, distributed acoustic sensing, large-N array, active surface seismic, vertical seismic profiling, seismic imaging of faults and fracture zones, laboratory experiments and novel instrumentation. We also welcome submission of abstracts on modeling studies at all scales, seismicity forecasting models, hazard and risk analysis studies as well as presentations dealing with good-practice guidelines and risk assessment procedures that would help in reducing commercial costs and enhancing the safety of future geothermal projects.

Please consider submitting your abstract to our session before the deadline on 12 January 2022, at 5 p.m Pacific. 

Detailed information on how to submit an abstract can be found at: https://www.seismosoc.org/meetings/submission-system/

Modeling and Simulation Forum #13 Recording

Utah FORGE Modeling & Simulation Forum #13


"Impact of injection rate ramp-up on nucleation and arrest of dynamic fault slip"

Presented by: Federico Ciardo (ETH-Zurich)

December 15, 2021 at 11 am MST

Injection of fluid into the subsurface is a common operation in many industrial applications, such as wastewater disposal, hydraulic fracturing and deep geothermal energy exploitation. One of the drawbacks of these engineering applications is the generation of seismicity that in some severe cases might lead to a complete shutdown of operations.

The injection scenario, either in terms of pressure or volumetric rate, is one of the key controlling parameters for fluid induced seismicity. Numerous studies on the effects of injection parameters on earthquakes nucleation and occurrence along faults have been carried out. Most of them, however, assume idealized injection scenarios such as constant fluid over-pressure or constant injection volumetric rate.

In this contribution, we investigate extensively the effect of a finite ramp-up of injection rate, commonly present in many realistic injection protocols, on slip stability along a planar frictional weakening fault under plane-strain conditions (see Figure). We solve the coupled hydro-mechanical problem and investigate all the slip development regimes in the problem parametric space, including stable a-seismic slip, nucleation of a finite size dynamic event and nucleation of a run-way dynamic rupture.

FIGURE >>> Plane-strain fault model

Our results suggest that injection-induced seismicity can be mitigated by controlling the fault pressurization rate, in the limit when fluid diffusion time scale is lower than injection ramp-up time scale. Analytical derivations support our numerical results. The findings of this work can be useful for practical designing of injection operations in hydro-shearing type of stimulations.


 

This is the 12th forum of the series and is intended to have an open format to present modeling and simulation, both completed and planned, as well as activities being conducted by the Utah FORGE Team.

This webinar has been recorded and is available for viewing

To follow along with the slides, the pdf of the presentation is available for download HERE

For previous forums and for the upcoming schedule check out the Modeling and Simulation FORUM page

Modeling and Simulation Forum #12 Recording

Utah FORGE Modeling & Simulation Forum #12


"Hybrid fracture/matrix modeling for well completion options evaluation"

Presented by: Lynn Munday and Somayajulu L. N. Dhulipala (Idaho National Laboratory)

November 17, 2021 at 11 am MST

Orientation and completion for well pairs that have been subjected to multi-zonal stimulation play a critical role in the long-term performance of an Enhanced Geothermal Reservoir. Here we present the development of a methodology to rapidly and efficiently numerically simulate mixed fracture-matrix flow systems for evaluation of well design and completion options. The methodology is based on a loose coupling framework, allowing the fracture and matrix systems to be meshed separately. The fracture system includes the integration of fracture growth and aperture data from well stimulation simulations of stochastically generated fracture networks. Automatic mesh refinement is used in the matrix simulation to resolve heat transfer near the fracture network. This simulation framework is used to efficiently determine optimal production and injection well placement using adaptive sampling.

This is the 12th forum of the series and is intended to have an open format to present modeling and simulation, both completed and planned, as well as activities being conducted by the Utah FORGE Team.

This webinar has been recorded and is available for viewing

To follow along with the slides, the pdf of the presentation is available for download HERE

For previous forums and for the upcoming schedule check out the Modeling and Simulation FORUM page

Partner Spotlight – UGS

The Utah Geological Survey (UGS) is a state agency and division of the Utah Department of Natural Resources. The UGS provides timely scientific information about Utah’s geologic environment, resources, and hazards. Our work is focused on the generation and dissemination of geologic information to a variety of stakeholders that include the general public, and a diverse group of private, local, state, and federal entities. Seven specialized programs comprise the UGS: Energy & Minerals, Geologic Hazards, Geologic Information & Outreach, Geologic Mapping, Groundwater & Wetlands, Data Management, and Paleontology. As part of its mission the UGS also houses unique collections of geoscience data and physical samples including core and cuttings relating to Utah’s geothermal and other geologic resources.


The UGS strives to promote values that include excellence, integrity, and objectivity in everything we do; responsible stewardship of Utah’s geologic and energy resources; the free exchange of ideas and information in a spirit of cooperation; and provide prompt and courteous service to our customers and stakeholders.

The UGS celebrates and supports diversity, equity, and inclusion in the Geosciences and aims to maintain a safe and inclusive environment for our employees and the public we serve.

The UGS has been involved with the Utah FORGE project since its inception in 2014. UGS work on the FORGE project is based on strong collaboration with researchers at the Energy and Geoscience at University of Utah, the Idaho National Laboratory, and many others.  Early work included characterizing aspects of the site that include; the thermal setting, the groundwater system, geophysical setting focusing on gravity and basin depth, and geologic setting of the site and adjoining Mineral Mountains. This work culminated in the awarding of the FORGE project to the Utah site, and subsequent site development as a unique national laboratory focused on novel techniques to stimulate and develop low permeability hot rock resources.

Current UGS work is focused on campaign gravity, GPS deformation, and groundwater monitoring on and adjoining the Utah FORGE site. The goal of this work is to constrain baseline and temporal trends both prior to and during development and stimulation activities at the site. Recent work has included installation of two continuous GPS stations and regional groundwater sampling to constrain geochemistry as it relates to the geothermal setting at the site. Additional work has focused on refining and better constraining the conceptual geologic and hydrologic setting of the Utah FORGE site and adjoining North Milford Valley.


Cartographers at the UGS have recently completed a readily accessible geoscientific webmap that presents various background datasets (infrastructure, geologic, thermal, hydrologic, etc.) for the FORGE site. It is accessible at https://geology.utah.gov/apps/forge/. The UGS also assists with well permitting and acts as liaison with State of Utah agencies that regulate various parts of the Utah FORGE development.