Small Scale Geothermal Development - an Example of Cooperation Between Land Owner and Electrical Cooperative

Abstract

Throughout the world exists the potential of small scale (less than 5 MWe) power generation utilizing lower temperature geothermal resources (less than 150 degrees C). With the development of lower temperature binary technology, low temperature power production is feasible. Small scale development can be especially efficient and cost effective in the more remote areas where power transmission systems are non-existent or do not have the capacity to transmit large amounts of power. A project in Paisley, Oregon by Surprise Valley Electrification Cooperative is an example of what a local rural electric cooperative can do to develop a low temperature geothermal resource. In the 1900's, rural electric cooperatives played a major role in the United States to bring electric power to rural America. Today they are in a key position to promote developing small scale geothermal power in their service territory. The Paisley Surprise Valley Electric project started with discussions between the rural cooperative and a local rancher who had a well which was flowing over 1000 gpm at a temperature of 115 degrees C. This well was used only for irrigation after discharging into a large pond to allow the water to cool before applying to crops. Initial geo-technical studies identified faulting and fracturing which appeared to control the geothermal fluids. Two production wells were drilled into the fracture zones at depths of 415 and 384 meters respectively. Testing of the wells indicated a capacity for a potential 3 to 4 MWe power plant. After completion of an injection well to a depth of 824 meters, the design effort for a 3.5 MWe binary plant was initiated. The power plant is to be placed on site in the spring of 2014 with power on line by the summer of 2014. Data will be collected on the reservoir and power plant along with the experience of the rural electric cooperative in owning and operating a power plant. This information will be available by 2015 and presented in the paper. Throughout the world exists the potential of small scale (less than 5 MWe) power generation utilizing lower temperature geothermal resources (less than 150 degrees C). With the development of lower temperature binary technology, low temperature power production is feasible. Small scale development can be especially efficient and cost effective in the more remote areas where power transmission systems are non-existent or do not have the capacity to transmit large amounts of power. A project in Paisley, Oregon by Surprise Valley Electrification Cooperative is an example of what a local rural electric cooperative can do to develop a low temperature geothermal resource. In the 1900\'s, rural electric cooperatives played a major role in the United States to bring electric power to rural America. Today they are in a key position to promote developing small scale geothermal power in their service territory. The Paisley Surprise Valley Electric project started with discussions between the rural cooperative and a local rancher who had a well which was flowing over 1000 gpm at a temperature of 115 degrees C. This well was used only for irrigation after discharging into a large pond to allow the water to cool before applying to crops. Initial geo-technical studies identified faulting and fracturing which appeared to control the geothermal fluids. Two production wells were drilled into the fracture zones at depths of 415 and 384 meters respectively. Testing of the wells indicated a capacity for a potential 3 to 4 MWe power plant. After completion of an injection well to a depth of 824 meters, the design effort for a 3.5 MWe binary plant was initiated. The power plant is to be placed on site in the spring of 2014 with power on line by the summer of 2014. Data will be collected on the reservoir and power plant along with the experience of the rural electric cooperative in owning and operating a power plant. This information will be available by 2015 and presented in the paper.