Repurposing Idle Oil and Gas Wells to Thermal Energy Storage Systems for Long Duration, Dispatchable and Distributed Electricity Delivery. There are over 39,000 idle oil and gas wells in California. State and local regulators apply pressure to abandon these wells, but their abandonment comes at a significant and often underfunded cost, and many are sources of actual or potential methane emissions. Converting these assets to Thermal Energy Storage Systems (TES) permanently seals off emissions, provides Long Duration Energy Storage (LDES) and leverages tax credits available in the Inflation Reduction Act (IRA) for this conversion. Idle oil and gas wells are ideal environments for a TES due to their large volumes and high thermal insulation. The conversion begins with standard abandonment protocols followed by the installation of a novel closed-loop heat exchanger system within the wellbore. Using surplus renewable electricity during peak production periods, RHTHPs transfer high-temperature TES into the borehole. This stored energy can later be dispatched through above-ground Carnot Battery systems, enabling flexible LDES independent of geothermal gradients. The modular design adapts to various site conditions and energy demands throughout California and the other 31 petroleum producing states where there are aging oil and gas wells. Moderated by Analiese Andersen, Account Executive, MicroThermal Energy Speaker: Bill Bartling, Co-Founder, Geo2Watts and Advisor for Lillianah Technologies