Conceptual Modelling of Two Large-Scale Mine Water Geothermal Energy Schemes: Felling, Gateshead, UK

Abstract

A conceptual model is presented of two MW-scale low enthalpy mine water geothermal heat pump schemes that are being developed in Tyneside, UK. The Abbotsford Road scheme (54.955° N 1.556° W) is operating (as of May 2021) at 20–30 L/s, abstracting groundwater (and heat) from an unmined Coal Measures Upper Aquifer System (UAS) and reinjecting to the deeper High Main Aquifer System (HMAS), associated with the High Main (E) coal workings and the overlying High Main Post sandstone. A similar scheme, 700 m away at Nest Road (54.959° N 1.564° W), abstracts at 40 L/s from the HMAS, recovers heat from the mine water and reinjects the thermally spent water to deeper workings associated with the Hutton (L), Harvey-Beaumont (N) (and possibly other) coal seams, termed the Deep Mined Aquifer System (DMAS). The three aquifer systems are vertically discontinuous and possess different hydraulic (storage, transmissivity and continuity) properties that would have been near-impossible to predict in advance of drilling. At the sites, 10 boreholes were drilled to obtain five usable production/reinjection boreholes. Development of mine water geothermal energy schemes thus carries a significant project risk, and also a potential ongoing maintenance burden related to iron hydroxide scaling. These do not preclude mine water geothermal as a useful low carbon heating and cooling technology, but the involvement of skilled hydrogeologists, hydrochemists, mining and groundwater engineers is a pre-requisite.

Clean Energy Technology Applications on US Mine Land: Technical Analysis

“…It is important to understand the legal issues and start planning early. Demanding regulatory challenges may exist (Banks et al 2022).…”

Heat Recovery Potential and Hydrochemistry of Mine Water Discharges From Scotland’s Coalfields

“…As an example of the extent of mine working connectivity, the South Lanarkshire Farme Colliery, when active, was connected to other collieries over a scale of kilometres (Monaghan et al, 2017;Monaghan et al, 2022b). However the groundwater flow properties in mine workings (Younger and Adams, 1999) and their response to pumping (Banks, 2021;Banks et al, 2022) remain largely unpredictable before system installation and hydraulic characterisation. Similarly, temporal evolution of groundwater hydraulics in shallow mines may have implications for mine water thermal abstraction (Andrews et al, 2020).…”

“…The use of open loop abstraction-reinjection (well doublet) heat exchange systems based on shallow groundwater is globally widespread (Jessop et al, 1995;Verhoeven et al, 2014;Ramos et al, 2015;Walls et al, 2021;Monaghan et al, 2022a;Banks et al, 2022), and is similar to configurations found in other geothermal reservoir types such as hot dry rock and hot sedimentary aquifers (Limberger et al, 2018;Reinecker et al, 2021). However, there are alternative configurations by which mine water's thermal energy can be harnessed (Banks et al, 2019;Walls et al, 2021), each accompanied by varying drilling costs and project risks (Monaghan et al, 2022b).…”

“…However, there are alternative configurations by which mine water's thermal energy can be harnessed (Banks et al, 2019;Walls et al, 2021), each accompanied by varying drilling costs and project risks (Monaghan et al, 2022b). Detailed understanding of mine water geothermal energy resource size and sustainability remains largely in its research phase, with increasing numbers of projects being started (Walls et al, 2021;Monaghan et al, 2022a;Banks et al, 2022). Owing to the heterogeneous nature of mine workings, each project has unique hydrogeological properties, thus uncertainty around the speed and extent of heat migration within mines and initial resource scale and availability are regarded as significant project risks during the planning stage (Walls et al, 2021).…”

Mine water as a source of energy: an application in a coalfield in Laciana Valley (León, NW Spain)

“…Even low-temperature (low enthalpy) mine water resources might provide direct-use geothermal energy for space heating (Preene and Younger 2014 ). Geothermal is the most common energy use of mine water, particularly at coal mines, and there are applications in several countries in Europe and North America (Banks et al 2022 ; Walls et al 2021 ; Menéndez et al 2020 ; Andrés et al 2017 ; Peralta et al 2015 ; Watzlaf and Ackman 2006 ).…”