Did you know… geothermal wells can be highly deviated too?

Did you know... geothermal wells can be highly deviated too?

Just as in the oil industry, the first geothermal wells were all vertical, which remains common practice mainly because it is cost-effective. The maximum depth is typically about 10,000 feet (3 km). Deviated geothermal wells have been drilled too, extending laterally over horizontal distances up to about 5,000 feet (1.5 km) and dipping at angles of less than 45° as measured from the vertical. In most geothermal fields, the rock formations are made up of volcanic and sedimentary rocks.

New groundbreaking developments are now happening in the geothermal industry borrowing methods used for unconventional hydrocarbon development. Recently, a well having a long horizontal leg was drilled for the DEEP geothermal project in the Williston Basin, Saskatchewan, Canada.

The type of rocks being drilled into for geothermal development are relevant because up until now very few have reservoirs hosted by granitic rock, which is abrasive and hard on wear and tear of downhole equipment. Examples of such wells include 14-2 at Roosevelt Hot Springs, WD-1A at Kakkonda, Habanero 1 in the Cooper Basin, 33A-7 at Coso and OTN-3 in Finland. Of these, WD-1A has the hottest bottom hole temperature (~500°C), and OTN-3 is the deepest, but for this rock type, highly deviated wells are absent.

The new deep well at Utah FORGE, 16A(78)-32 is thus notable. It shows that the drilling of sub-horizontal well trajectories in granitoid are achievable. Such highly deviated wells are required for EGS wells in order to intersect a large number of sub-vertical fractures and to maximize energy production.

Figure showing the geothermal well profiles, host rocks and deviation angles: conventional wells in red; sedimentary basin wells in green (Saskatchewan, Canada; Groß Schönebeck, Germany); metamorphic-plutonic well in blue (Helsinki, Finland); granitoid wells in black (Roosevelt Hot Springs, Utah; Kakkonda, Japan; Cooper Basin, Australia; Soultz-sous-Forêts, France; Coso, California); granitoid well in pink (Utah FORGE).  

References

Ayling et al. 2016, Geothermics 63, 15-26. https://www.sciencedirect.com/science/article/pii/S0375650515000395

Kwiatek et al. 2019, Science Advances,5 (https://advances.sciencemag.org/content/5/5/eaav7224)

Ledésert & Hébert 2012,  Heat Exchangers - Basics Design Applications, 447-504, https://doi.org/10.5772/34276

Muraoka et al. 1998, Geothermics, 27:507-535. https://www.sciencedirect.com/science/article/pii/S0375650598000315

https://deepcorp.ca/canadas-first-geothermal-production-and-injection-well-test-exceeds-expectations-first-20-mw-facility-in-design-phase/

Sabin et al 2016, Proceedings Stanford Geothermal Workshop (https://pangea.stanford.edu/ERE/pdf/IGAstandard/SGW/2016/Sabin.pdf)

Zimmerman et al. 2010, Geothermics, 39, 59-69 (https://www.sciencedirect.com/science/article/pii/S0375650509000674)

Did you know… that the first wells were drilled over 2000 years ago?

Did you know that the first wells were drilled over 2000 years ago?

Drilling is an ancient technology and it has long been used to explore for natural resources and to produce fluids such as water, brine, oil and gas that occur underground. The Chinese drilled shallow wells over 2000 years ago to produce brine. The first oil wells were drilled in the 1800s and up through the early 1900s, wells were vertical and limited to depths of a few hundred to a couple of thousand feet. By the 1970s, depth records were being broken starting with Bertha Rogers No. 1 which was drilled to over 31,000 feet (9.5 km) to explore for gas in the Anadarko basin, Oklahoma, USA. In 1979, the Kola Superdeep scientific well in Russia was drilled to over 40,000 feet (12.2 km), making it the deepest well in the world.  In 2009, the deepest oil well was completed to 35,000 feet (10.6 km) from the Deepwater Horizon platform in the Gulf of Mexico.

The idea of drilling a slanted deviated well by directional drilling was realized in the 1930s. Today, the drilling of highly deviated wells is commonplace in the exploration and production of oil and gas reservoirs. The Chayvo oil field in Russia is the site of several record-breaking deviated wells that are drilled to depths of about 3,000 feet (0.9 km) with a long horizontal reach exceeding 40,000 feet, the longest of which is O-14. For comparison, geothermal wells are generally drilled to no more than 10,000 feet (3 km), and if deviated, they are done so at modest angles of less than 45°.

There are several reasons for drilling deviated wells such as increasing the section or length of well interval through rocks that are rich in oil (or gas). In some cases, there are obstacles (e.g., town or lake), which means the resource has to be accessed from the side rather than vertically from the surface. In other cases, there are logistical advantages to clustering a number of deviated wells on a single pad as is common in offshore oil platforms.

Figure shows the depth ranges of the deepest and longest wells in comparison to wells that are commonly drilled in geothermal production fields.

References

https://www.nationaldriller.com/drilling-history

https://www.maritime-executive.com/article/sakhalin-1-sets-another-drilling-record

https://www.statista.com/statistics/479685/global-oil-wells-by-depth/

https://en.wikipedia.org/wiki/Kola_Superdeep_Borehole

Utah FORGE and UofU’s Department of Communication partner up

In yet another example of inter-departmental collaboration, Utah FORGE, a geothermal energy research project, is delighted to be working closely with Dr. Sara K. Yeo in the University’s Department of Communication, within the College of Humanities.

The research being conducted by Utah FORGE near the town of Milford is focused on enhanced geothermal systems (EGS) technologies. The project is testing the tools and technologies to develop a geothermal resource where none exists naturally. If successful, these methods can be applied virtually anywhere in the world, providing a clean, inexhaustible energy source.

Harnessing the potential of geothermal energy could provide a great boost to the nation’s energy portfolio. Indeed, scientists suggest if we can tap just 2% of the energy found between 2 and 6 miles below the Earth’s surface, we would have more than 2000 times the energy used in the U.S. every year. It is literally the heat beneath our feet.

Public surveys indicate, however, that most people don’t know much about geothermal energy, and it’s seldomly included in discussions about renewable energy sources.  To better understand the current level of understanding and familiarity with geothermal energy, Utah FORGE is working with Dr. Yeo on a capstone course which includes surveying individuals about their awareness, knowledge, and opinions of geothermal energy.

“This is a unique opportunity for the students to put into practice the theories we discuss in class,” said Sara K. Yeo, Ph.D. and the professor conducting the capstone. “With the collaboration of the Utah FORGE team, the students developed the questions and determined the scope of the survey.”

“Our collaboration with Dr. Yeo is an exciting aspect of this project. It will provide us with a baseline from which we can judge the progress of our efforts to educate the public about geothermal energy and EGS,” said Joseph Moore, Ph.D., principal investigator of the project.

The 15-20-minute survey includes questions seeking to ascertain the public’s general understanding of geothermal energy and EGS. Responses are being obtained from 1000 individuals in 11 states across the western U.S. The capstone course will be repeated in the Fall Semester of 2021 to allow for a longitudinal data set to be created.

The Utah FORGE project is being managed by the Energy & Geoscience Institute at the University of Utah. Funding for the project is being provided by the US Department of Energy. It is one of the largest non-medical grants the University of Utah has ever received.

The University of Utah is no stranger to geothermal energy – it is purchasing 20 megawatts of geothermal electricity annually from Cyrq Energy, a geothermal developer actively working in Utah and Nevada.  Additionally, the Gardner Commons Building is entirely powered by that geothermal energy located just beneath our feet. With nearly half of its energy needs being met by renewable sources, the University of Utah is ranked eighth in the Green Power Partnership Top 30 College & University rankings.

 

December 22, 2020

Utah FORGE and the College of Education develop a new partnership

Inter-departmental cooperation has always been a hallmark of success for the University of Utah. The latest example of this cooperation is found in two seemingly disparate groups: Utah FORGE, a geothermal energy research project, and the College of Education.

Harnessing the potential of geothermal energy could provide a great boost to the nation’s energy portfolio. Indeed, scientists suggest if we can tap just 2% of the energy found between 2 and 6 miles below the Earth’s surface, we would have more than 2000 times the energy used in the U.S. every year. It is literally the heat beneath our feet. However, most people don’t know much about geothermal energy, and it’s rarely included in discussions about renewable energy sources.

Utah FORGE and the College of Education are working to change that. Building on the research Utah FORGE is conducting near Milford, in southwestern Utah, the College of Education is creating lesson plans which include geothermal energy as part of topic discussions around renewable energy.

“This is a unique opportunity for the Urban Institute for Teacher Education (UITE) in the College of Education,” said Mary D. Burbank, Assistant Dean and Director. “We consistently strive to advance the material taught in schools both in Utah and around the country. This collaboration with Utah FORGE allows us to introduce important new subject matter to students of all ages.”

Ph.D. candidate Tamara Young from the Department of Physics and Astronomy and Assistant Professor Lauren Barth-Cohen from the Department of Educational Psychology are working on the lesson plans. These plans are designed to incorporate the latest Utah science with engineering education (SEEd) standards and include hands-on and virtual heat conduction experiments, data interpretation segments, and group discussion activities. The plans are intended for K-12 students as part of the overall science curriculum.

“We are so excited to be collaborating with our colleagues at the College of Education. Their long record of innovation is an amazing resource for us to help build overall understanding about Utah FORGE and geothermal energy in general,” said Joseph Moore, Ph.D., Principal Investigator of the project.

The goal of Utah FORGE’s research is to test tools and technologies for the creation of a geothermal resource where none exists naturally. If successful, these methods can be applied virtually anywhere in the world, providing a clean, inexhaustible energy source.

The Utah FORGE project is being managed by the Energy & Geoscience Institute at the University of Utah. Funding for the project is being provided by the US Department of Energy. It is one of the largest non-medical grants the University of Utah has ever received.

The University of Utah is no stranger to geothermal energy – it is purchasing 20 megawatts of geothermal electricity annually from Cyrq Energy, a geothermal developer actively working in Utah and Nevada.  Additionally, the Gardner Commons Building is entirely powered by that geothermal energy located just beneath our feet. With nearly half of its energy needs being met by renewable sources, the University of Utah is ranked eighth in the Green Power Partnership Top 30 College & University rankings.

December 3, 2020

Did you know… that Reykjavík is a city of geothermal energy?

Did you know… that Reykjavík is a city of geothermal energy?

Did you know that the city of Reykjavík, the capital of Iceland, is widely recognized for its geothermal energy? Many first think of the word ‘ice’ when hearing Iceland, but surprisingly Iceland is also known for its use of Earth’s heat. Due to its geological location directly on the mid-Atlantic ridge, it is constantly supplied by an enormous amount of underground magmatic and geothermal heat. The literal translation of Reykjavík is “steamy bay” that comes from the steam discharge associated with natural geothermal activity.

Aware of the underground heat available, Icelanders have learned to adapt to their environment. Since the arrival of the first Scandinavian settlers in the late 800s, Icelanders have utilized geothermal sources for bathing and cooking. One of their popular traditional foods, Hverabrauð, is a bread loaf cooked in the steam from a geyser for 24 hours. Up into the early part of the 20th century, coal was the main source of energy and air pollution was a serious problem. To address this, the first geothermal pipelines were installed in 1934, and since then Reykjavík has been continuously expanding geothermal utilization. Reykjavík now has the largest district heating system in the world (700 MWthermal), which is run by Orkuveita, and more than 60 million cubic meters of hot water flow through the distribution system. Hot water supply comes from low temperature geothermal areas around Reykjavik and from high temperature geothermal fields in the Hengill area to the east of the city. These hotter resources are mainly used to generate electricity, but a significant amount of heat also supplies the district heating scheme. The combination of geothermal fields and hydroelectric dams means that more than 99% of all the electricity used in Iceland comes from renewable sources.

 

References:

https://adventures.is/information/geothermal-energy-iceland/

https://icelandmag.is/article/nine-fascinating-facts-about-geothermal-energy-and-reykjavik

https://pangea.stanford.edu/ERE/pdf/IGAstandard/ISS/2004Poland/3_5_gunlaugsson.pdf

Geothermal Resources Lecture #1

Conventional vs Unconventional …

Dr. Stuart Simmons introduces us to renewable energy in the 21st century – this month learn about conventional geothermal resources and the basic concepts of heat transfer, enthalpy and power as well as where and how geothermal energy is utilized.

 

This is the first lecture of the geoscientific series of lectures.The lectures will reside on our

Geothermal Resources Lecture Series page