Harnessing Advanced Geothermal Baseload through Power Systems Integration: A Strategic Pathway to Energy Resilience and Enhanced Economic Stability for UK High Energy Users.

High-energy users in the UK face critical challenges balancing Net Zero ambitions, energy security, cost volatility, and operational resilience. Significant reliance on the National Grid for baseload electricity characterises most UK high-energy users, creating exposure to fluctuating grid carbon intensity and grid-related vulnerabilities. Conventional on-site variable renewable energy sources (VRES) like solar photovoltaics and wind turbines, while contributing to decarbonisation, cannot reliably meet substantial baseload power demands due to their inherent intermittency, limiting pathways to energy independence and cost predictability. This thesis investigates the potential of Advanced Geothermal Systems (AGS), viewed here as closed-loop well configurations primarily utilising conduction/convection heat transfer downhole, representing a potentially lower-risk alternative to traditional hydrothermal or Enhanced Geothermal Systems (EGS) which rely on direct subsurface geological interaction to provide firm, low-carbon, on-site baseload power generation. The focus is on leveraging AGS-derived thermal energy for electricity production (with waste heat potential) and integrating this dispatchable resource within the private high-voltage (HV) networks of large consumers. The research evaluates the technical feasibility, economic viability, and resilience enhancement offered by behind-the-meter integrated AGS solutions for a case study site. The research aims to evaluate the technical feasibility, economic viability, and resilience enhancement offered by integrated AGS solutions. It utilizes a detailed case study of the University of Exeter's Streatham Campus, a high-energy user (>26 GWh/year) with a private HV network and ambitious 2030 Net Zero goals. The methodology encompasses power systems modelling of 'as-is' and ‘Heat Electrification’ scenario’s using detailed load analysis and AGS-integrated 'to-be' scenarios, comprehensive techno-economic analysis, and resilience assessments during simulated grid outages. The technical integration assessment aligns with established UK engineering standards for generation connection, such as Energy Networks Association (ENA) Engineering Recommendation G99, adapted for operation within the private HV network. A significant contribution is the development and validation of a statistical load modelling technique derived from existing literature, generating high-resolution campus-wide load profiles from a small limited half-hourly sub-metering dataset, addressing a common barrier for large estates. Key findings indicate that on-site AGS power generation presents the most technically viable pathway for significant baseload decarbonisation at the Streatham Campus, exceeding the energy contribution potential of space-constrained VRES deployment. The statistical load modelling yielded credible, validated profiles despite initial data limitations. While the existing campus HV network demonstrates sufficient capacity under current loads, projected electrification and demand growth could introduce network constraints, potentially mitigated by strategically located geothermal generation nodes. Although complete energy autonomy via VRES alone appears challenging in the near term, the study concludes that strategically integrated AGS offers a robust approach to substantially improve campus energy resilience against grid disruptions and accelerate progress towards Net Zero objectives, potentially through site-wide integration or dedicated supply to critical facilities. This research provides an evidence-based framework demonstrating how AGS integration can enhance energy supply stability, operational resilience, and decarbonisation for the University of Exeter, and many other analogous high-energy consumers. Beyond the immediate case study, demonstrating AGS as a viable on-site baseload solution here could signal significant industry-wide implications for enhancing energy resilience and accelerating decarbonisation for high-energy users across the UK. While the developed framework and findings for the University of Exeter provide a strong model, it is recognised that the specific quantitative outcomes and economic sensitivities may differ for other high-energy users, particularly those in heavy industry with distinct load profiles and economic drivers. Nevertheless, this research offers transferable insights into the strategic role AGS can play in the UK's energy transition.<p></p>