A subsurface geological model to assess geothermal energy and hydrogen storage potential in North West England

Abstract

The main aim of this PhD is to construct a 3-dimensional geological model of the subsurface beneath Greater Manchester and the Cheshire Basin. Ideas on the application of this model to different aspects of the energy transition have been developed during the PhD study period. An integrated regional interpretation of the Cheshire Basin, and a play fairway mapping exercise, have been used to evaluate the geothermal potential of the Triassic Sherwood Sandstone Group and the Permian Collyhurst Sandstone Formation. This new interpretation has highlighted two target areas for further exploration of direct-use geothermal resources. Potential Carboniferous aquifer targets occur in the Millstone Grit and Carboniferous Limestone Groups, below southern Manchester. These targets are evaluated using a new seismic interpretation and, mapping indicates that these potential aquifers have temperatures of 65-100degC. At flow rates of around 18 to 28 litres/second for the Millstone Grit and Carboniferous Limestone respectively, these aquifers could generate thermal power at the approximate rate of 4MW. A more detailed understanding of the geology and hydrogeology of these aquifers is required, particularly the roles of fractures and karst in fluid flow. Greater Manchester like most industrial cities in the north of England was built on coal deposits which were extensively mined during the industrial revolution. In this thesis I have investigated the potential of the former Bradford Colliery to supply mine water geothermal heat to the Etihad Campus, close to Manchester City Centre. Calculations show that with abstraction rates of 40 litres/second and taking 10degC of useable heat from the produced fluid (deltaT), abstraction from the Parker Seam at 535 metres could supply thermal energy at a rate of 2.3MW. A key part of the United Kingdom's Net Zero strategy is the use of hydrogen as a fuel. it is generally recognised that to balance supply and demand, large scale hydrogen storage will be required. Storage of hydrogen in salt caverns is a proven technology and a new interpretation has been made of the depth and thickness Northwich Halite Member, which is currently used to store natural gas. Using a minimum depth for safe operation of 500 metres, and a minimum thickness of 130metres, between 0.27 and 0.56 cubic kilometres of useable halite is available for storage in the Cheshire Basin. The open access databases built during this research, both in Petrel and ArcGIS, have a practical value to companies , academics and councils working towards the Net Zero targets locally and nationally.

Date of Award	18 Jun 2024
Original language	English
Awarding Institution	The University of Manchester
Supervisor	Mojgan Hadi Mosleh (Supervisor), Catherine Hollis (Supervisor), Mads Huuse (Supervisor), Lin Ma (Supervisor) & Rhodri Jerrett (Supervisor)