Geology, Energy and Storage Underground Greater Manchester

As part of the global drive to reduce Carbon emissions, the UK is currently aiming to achieve Net Zero carbon emissions by 2050, whilst Greater Manchester is aiming for Net Zero by 2038. This will require extensive harnessing of the clean energy arising from the Earth's internal heat production as well as energy storage in the form of underground gas storage, and carbon sequestration. The sedimentary strata beneath Manchester, and in the surrounding area, have the potential to both provide low enthalpy geothermal heat, store hydrogen and hydrocarbon gases and sequester CO2.

This project aims to construct a 3-dimensional geological and physical property model of the subsurface beneath Greater Manchester and the Cheshire Basin. The overall purpose of the model is to inform future decisions about utilisation of the subsurface under Greater Manchester and its surroundings for geothermal energy and/or geological storage of gas and CO2.

The approach involves the integration of large amounts of legacy subsurface data including, but not limited to, seismic data, well log data, borehole data, outcrop data, core and thin section data. Data will be loaded and interpreted in dedicated 3-D interpretation software. These data are available from public repositories at the British Geological Survey and the UK Onshore Geophysical Library and the Coal Authority.

Major intervals of interest include the Carboniferous Coal Measures (for gas and potential for CO2 sequestration) and Lower Carboniferous Limestone (geothermal reservoir). Additionally the Permian and Triassic salt layers and intervening sandstones and mudstone will be assessed for both underground gas storage and geothermal energy.

The geological model will contain information of lithology, thickness, lateral continuity, age and fault and fracture distribution. Furthermore a rock property model will be constructed to describe subsurface variations in pore volume, permeability, temperature and fluid salinities. This will allow the capacity of key strata to reservoir and flow fluids, which are essential parameters in assessing their ability to store gas, sequester CO2 and provide low enthalpy heat.

The subsurface model of the underground is the first step for implementing several types of projects essential for a successful Energy Transition on the path to Net Zero Carbon emissions. These require a fuller understanding of subsurface geology, physical properties (porosity, permeability, stiffness, plasticity) and responses to different loading conditions, bacterial activity, etc, which are vital to understanding changes in subsurface storage capacity, fluids/gas stored underground, and to design installations for waste disposal or gas or heat storage, heat extraction, etc To support this an integrated physical and geomechanical model or models will be created to allow simulations of injection, extractions processes and any bi-products caused by microbial activity and other poorly understood subsurface reactions.

In summary a complete new structural and stratigraphic model will be constructed, which will form the basis for additional studies on the energy transition in NW England largely based around subsurface energy storage, geothermal energy potential and carbon dioxide sequestration.