Cornell well on its way to net zero CO₂ with Earth Source Heat project.

Cornell University contracted SLB to construct, characterize, and drill a 10,000-ft well on campus. Successful testing and characterization enabled exploratory studies for using the well as a geothermal resource to heat the campus.

Cornell University, an Ivy League institution in Upstate New York, is developing an innovative Earth Source Heat (ESH) geothermal system that, upon completion, will use the Earth's internal heat to warm the campus without using fossil fuels. The project is a research collaboration and a major component of the university's goal of achieving carbon neutrality in the next 12 years. The faculty and staff of Cornell have a history of creating and deploying new energy systems, such as Lake Source Cooling. The main objective for the exploratory well is to extract data to determine whether deep geothermal heating is a viable option for the Ithaca campus in its quest to achieve carbon neutrality by 2035.

Air drilling is typically used during the first stage. However, air drilling produces high levels of noise pollution, so being on a university campus demands another option. Another drilling company suggested a freshwater gel mud system to reduce noise pollution. However, this solution needed to address the potential for formation washouts while drilling through salt and shale formations throughout various intervals.

Most wells drilled in the Utica Formation use nonaqueous fluid mud systems to drill the production interval. Since the main objective of this exploratory well was to extract data about the underground system to determine whether deep geothermal heating is a viable option for the Ithaca campus, a water-based system was necessary to avoid contaminating the reservoir with oil-based fluids.

Cornell University awarded SLB a contract for integrated services to construct and characterize a stratigraphic well on the campus. HydraGlyde^™ high-performance water-based drilling fluid system was chosen because it avoids washouts while drilling through salt formations and reduces the mobilization of interbedded salt, dolomite, and shale formations. In addition, HydraHib^™ shale inhibitor was added to the mix as it guards against wellbore instability in shale formations.

The well was drilled to depths nearing 10,000 ft, with 300 ft drilled into the crystalline basement under sedimentary layers. The well production incorporated several innovative technologies, including DrillPlan^™ coherent well construction planning solutions, DrillOps^™ on-target well delivery solutions, and MDT^™ modular formation dynamics tester. In addition, the systems, solutions, and tester were deployed with a new 10K dual-packer system for state-of-the-art sampling and characterization.

The well was drilled to the target zone with no fluid performance issues and was successfully tested and characterized. No wellbore instability issues occurred. Wireline logs also showed no significant or concerning washouts in the Syracuse salt formation. All casing runs occurred without any problems. The successful completion of the drilling stage enables exploratory studies to use the well as a geothermal resource to heat the campus. When put into service, the Earth's internal heat will keep temperatures near or above the boiling point of water. Water circulated through the wells returns to the surface as hot water for campus heating and potential electricity production. Using ESH is central for Cornell to achieve its carbon neutrality goal by 2035.