This funding opportunity announcement (FOA) will enable technologies to provide reliable and flexible, emissions-free electricity generation and deliver unique technology solutions to America’s heating and cooling demands; directly supporting the Administration’s goals of carbon pollution-free electricity by 2035 and net zero greenhouse gas (GHG) emissions by 2050.

This FOA intends to facilitate improvements in two key facets of geothermal energy production and application through reducing the cost of geothermal wellbore construction (Topic Area 1) and managing the storage of produced heat (Topic Area 2).

Topic Area 1 – High Temperature Tools for Well Integrity Evaluation: Seeks applications to address wellbore tools and technology to supplement and advance beyond currently available off-the-shelf (OTS) solutions provided by the oil and gas industry for cement and casing evaluation. Current solutions are suitable for the upper end of the oil and gas industry’s temperature needs but are not generally considered adequate for use in hotter, EGS systems. Current OTS solutions may be implemented in certain situations that use wellbore cooling methods, but these situations do not drastically increase the operable temperature range and available time for downhole interrogation. Reliance on secondary temperature mitigation for logging can substantially increase time and costs while degrading reliability and repeatability.

Topic Area 1 funding of up to $23.1 M will support projects that address the shortcomings of current downhole logging and monitoring tools to provide more cost-effective and consistent methods of downhole evaluation of wellbore construction materials and practices. Confirmation of success and identification of adverse conditions will help to drive innovation in the practices and materials used in the casing and cementing space.

The goals of Topic Area 1 are to develop high-temperature well integrity evaluation tools and solutions that:

• Operate in high-temperature geothermal environments to provide consistent, high-resolution evaluation information.
• Operate in a manner which are not reliant on extraneous wellbore cooling or substantial mitigation of borehole conditions.
• Provide high-fidelity data to adequately characterize conditions that may present safety hazards, risk to the environment, and efficacy of wellbore construction for long-term operation.

Topic Area 2 – Utilization of Reservoir Thermal Energy Storage (RTES) Technology and Low-Temperature Geothermal Resources as part of an Industrial Process: seeks to demonstrate low-temperature (<130◦ C) RTES technology utilization as part of an industrial process with funding up to $7.9 M. RTES is a type of thermal energy storage that takes advantage of large subsurface storage capacities, geothermal gradients, and thermal insulation associated with deep geologic formations to store thermal energy to be extracted in the future for beneficial use on a variety of timescales. These systems often include three main components:

1. a heat source,
2. a subsurface formation or reservoir that does not intersect aquifer systems used for potable water and is suitable for storing and producing heated fluids, and
3. a heat exchange system that extracts heat and delivers it to the end user.

Previous GTO-funded work related to RTES includes the Beyond Batteries initiative and a laboratory research call for geothermal hybrids R&D. These activities have helped increase the understanding of various concepts, technologies, and innovations related to RTES—thus providing the groundwork necessary to move RTES into the demonstration phase. A recent report by Idaho National Laboratory summarized the current state of technology for RTES and presented modeling results that benchmarked anticipated RTES costs against other thermal storage technologies on a cost basis. Based on these foundations, GTO considers RTES technology to be at the readiness level for a pilot U.S. demonstration.