Feasibility of Deep Direct-Use Geothermal on the West Virginia University Campus-Morgantown, WV

Abstract

In 2010, research completed by the Southern Methodist University (SMU) Geothermal Laboratory estimated temperatures at reasonable drilling depths in the state of West Virginia (WV) were in the temperature range desirable for district heating. This higher temperature region extends from north-central WV (Monongalia County) to southeastern WV (Greenbrier County). The Morgantown campus of West Virginia University (WVU) is located within the north-central region, and as part of the 2016 study on Low-temperature Geothermal Play Fairway Analysis for the Appalachian Basin (GPFA-AB), Morgantown is identified as one of the priority locations for further analysis of the potential for deep direct-use (DDU) of geothermal energy. In this project, the feasibility of developing a Geothermal District Heating and Cooling (GDHC) system for the WVU campus in Morgantown, WV, to replace the current coal-fired steam heating and cooling system, is evaluated. In conjunction with our project partners, the West Virginia Geological and Economic Survey (WVGES), Lawrence Berkeley National Laboratory (LBNL), and Cornell University, our overall project objectives were to: 1) decrease the uncertainty and risk associated with developing the geothermal resource for use on campus at WVU, and 2) complete an optimized design for the geothermal system that minimized the delivered Levelized Cost of Heat (LCOH) across a range of possible DDU utilization scenarios. The economic analysis of the hybrid GDHC system is performed using GEOPHIRES [GEOthermal energy for the Production of Heat and electricity (IR) Economically Simulated, with “IR” representing electric current and resistance and referring to the electricity mode], developed at Cornell University. GEOPHIRES is modified to account for a hybrid geothermal natural gas system, and the BICYCLE levelized cost model is applied to calculate LCOH. The LCOH for the entire campus steam supply is in the range of 7.0 - 12.5 $/MMBTU, which is below the current cost of $15/MMBTU. Due to the high latent heat needed for conversion of hot water to steam, the hot water-based geothermal contribution to the current steam-based hybrid system would be low. Therefore, conversion of the steam-based system to a hot water-based system is considered in this analysis. Due to the large water flow rates needed for the system, multiple horizontal configurations are considered. Each configuration has two production wells and one injection well with a total production rate of 80 kg/s. The LCOH obtained for this hot water system is higher than the current cost. However, the LCOH estimated is based on a maximum production rate of 40 kg/s from a single production well; hence, well drilling costs for multiple wells are too high for the system to be economical. Therefore, the feasibility of the hot water-based system depends on the ability to produce high volumes of geothermal hot water from the Tuscarora sandstone to meet the peak demand. A geothermal DDU system at WVU is feasible to replace the existing coal-based system, given the geological and techno-economic analyses completed in this study. A DDU system would not only serve the campus of 33,000 students, but it would also serve Ruby Memorial Hospital, the largest hospital in West Virginia and West Virginia's only nationally certified Level 1 trauma center. It would also advance the efforts to achieve a reliable and clean energy source for the central steam generation system as part of WVU’s Sustainability Plan, which is managed under the WVU Office of Sustainability and the WVU Energy Institute.