Technical Papers
AltaRock Publications at Selected Geothermal Conferences 2009-2013
Microseismic Monitoring of Newberry Volcano EGS Demonstration, Cladouhos, T.T., Petty, S., Nordin, Y., Moore, M., Grasso, K, Uddenberg, M., Swyer, M., Julian, B., and Foulger, G., (2013), PROCEEDINGS, Thirty-Eighth Workshop on Geothermal Reservoir Engineering Stanford University, Stanford, California, February 11-13, 2013 SGP-TR-198. http://www.geothermal-energy.org/pdf/IGAstandard/SGW/2013/Cladouhos.pdf
Improving Geothermal Project Economics with Multi-zone Stimulation: Results from the Newberry Volcano EGS Demonstration, Petty, S. Nordin, Y., Glassely, W. and Cladouhos, T. (2013), PROCEEDINGS, Thirty-Eighth Workshop on Geothermal Reservoir Engineering Stanford University, Stanford, California, February 11-13, 2013 SGP-TR-198. http://www.geothermal-energy.org/pdf/IGAstandard/SGW/2013/Petty.pdf
Newberry Volcano EGS Demonstration—Phase I Results, Cladouhos, T.T., Osborn, W.L., and Petty, S., (2012), PROCEEDINGS, Thirty-Seven Workshop on Geothermal Reservoir Engineering Stanford University, Stanford, California, January 30-February 1, 2012 SGP-TR-194. http://www.geothermal-energy.org/pdf/IGAstandard/SGW/2012/Cladouhos.pdf
The Role of Stress Modeling in Stimulation Planning at the Newberry Volcano EGS Demonstration Project, Cladouhos, T., S. Petty, O. Callahan, W. Osborn, S. Hickman, and N. Davatzes (2011), PROCEEDINGS, Thirty-Sixth Workshop on Geothermal Reservoir Engineering, Stanford University, Stanford, California, January 31 - February 2, 2011. http://www.geothermal-energy.org/pdf/IGAstandard/SGW/2011/cladouhos.pdf
Fluid Diversion in an Open-Hole Slotted Liner, Petty, S., Bour, D., Nordin, Y., and Nofziger, L. (2011), PROCEEDINGS, Thirty-Sixth Workshop on Geothermal Reservoir Engineering, Stanford University, Stanford, California, January 31 - February 2, 2011. http://www.geothermal-energy.org/pdf/IGAstandard/SGW/2011/cladouhos.pdf
Newberry Volcano EGS Demonstration – Phase I Results, Osborn, W.L., Petty, S., Cladouhos, T.T., Iovenitti, J., Nofziger, L., Callahan, O., Perry, D.S. and Stern P.L. (2011), GRC Transactions, 35, 499-505. http://pubs.geothermal-library.org/lib/grc/1029284.pdf
Newberry Volcano EGS Demonstration Stimulation Modeling, Cladouhos, T.T., Clyne, M., and Nichols, M., (2011), GRC Transactions,33, pp. 317-322. http://pubs.geothermal-library.org/lib/grc/1029258.pdf
Injection Induced Seismicity and Geothermal Energy, Cladouhos, T., S. Petty, G. Foulger, B. Julian, and M. Fehler (2010). , GRC Transactions, 32, 1213-1220. http://pubs.geothermal-library.org/lib/grc/1028814.pdf
Toward More Efficient Heat Mining: A Planned Enhanced Geothermal System Demonstration Project, Cladouhos, T., S. Petty, B. Larson, J. Iovenitti, B. Livesay, and R. Baria (2009), GRC Transactions, Vol. 33, pp. 165‐170. http://pubs.geothermal-library.org/lib/grc/1028449.pdf
Enhanced Geothermal Systems or EGS
EGS projects produce electricity using heat extracted with engineered fluid flow paths in hot rocks. These pathways are developed by stimulating them with cold water injected into a well at high pressure and utilizing a variety of proprietary techniques developed by AltaRock which are the subject of its patent portfolio.
In the EGS power generation cycle, water is continuously injected down a well into the enhanced fractures, where it heats up as it flows through the rocks. The water is then brought to the surface in multiple production wells, and its heat is extracted to generate electricity in power plants. Finally, the water, depleted of its heat, is re-injected to be heated again in the fractures.
TZIM - Thermo-degradable Zonal Isolation Materials
Formally referred to as 'diverter technology' Thermo-degradable Zonal Isolation Materials or TZIM represents an important technological advancement in the development of EGS. TZIM is a biodegradable, non-toxic material injected with water into a production well during the stimulation or hydroshearing process. This material temporarily blocks water from the newly created fracture network. TZIM forms a shield around the well bore in the fracture network so additional fracture networks can be opened deeper in the well bore.
The hydroshearing process and opening of cracks creates movement and sound in the rock, resulting in microseismicity. The opening and growth of fractures during stimulation is mapped by real-time measurement of the microseismicity. Using a Microseismic Array (MSA) and AltaStim, AltaRock’s proprietary software, we can closely monitor the process. We’ll map the fracture network and generate a microseismic event map around the well bore, revealing the size, location and orientation of the fracture system.
Field Demonstrations
The Newberry EGS Demonstration currently being conducted in the Deschutes National Forest in Central Oregon could be a viable solution to our future energy challenges and the creation of a new energy economy. In Phase I, a team of scientists and engineers will review existing data about the Newberry EGS Demonstration site, conduct baseline measurements, develop plans and obtain permits for Phase II operations. In Phase II, an EGS reservoir will be created around a deep, existing well using AltaRock's proprietary methods and technology. In Phase III of the Newberry EGS Demonstration, we summarize the collected information to develop a conceptual model of a commercial-scale EGS system.
Microseismic Arrays
The hydroshearing process and opening of cracks creates movement and sound in the rock, resulting in microseismicity. The opening and growth of fractures during stimulation is mapped by real-time measurement of the microseismicity. Using a Microseismic Array (MSA) and AltaStim, AltaRock's proprietary software, we can closely monitor the process. We map the fracture network and generate a microseismic event map around the well bore, revealing the size, location and orientation of the fracture system.
