Geothermal Energy Storage
Researchers: Professor Andy Woods, Emma Lepinay
The Problem
As reliance on renewable energy sources like solar and wind power increases during the transition to Net Zero, we will become increasingly dependent on very intermittent sources of energy.
Work Needed
We need to work towards new energy storage solutions that work across long timescales to ensure that energy supply meets demand.
Our Work
We have been developing models to investigate the potential for large-scale underground energy storage solutions, including interseasonal solutions that store summer heat for use in winter.
Background
- The decarbonisation of heating must play a key role in the goal of reaching Net Zero by 2050; 37% of greenhouse gas emissions in the UK come from heating.
- A crucial challenge for the energy transition stems from the intermittency of renewable power generation (e.g. wind and solar energy)
- The potential of using geothermal technology to provide energy storage solutions is currently under-explored
Our Work
We have been developing new models for large scale thermal energy storage in the subsurface, exploring the potential for capturing industrial waste heat or thermal energy produced in the summer and storing it for use in the winter. This long term use of thermal energy storage represents a central element in the decarbonisation of heating systems and the supply of thermal energy to heat networks. This method of interseasonal heat storage could provide a scaled and rational solution to renewable heating systems for buildings, especially in new building projects.
We have developed a modelling software which incorporates a range of key challenges to understand how to optimise the design and operation of large-scale geothermal energy storage solutions, ranging from aquifer thermal storage to borehole arrays.

Collaborations
We are collaborating with industry and institutions, such as with St. John’s College Cambridge, to develop novel and practical solutions for thermal energy storage in this context (Lepinay and Woods 2024)
Publications
Lepinay, E. and Woods, A., (2024) ‘On Thermal Drift in a Double Well Aquifer Thermal Energy Storage System.’ In Proceedings of the 49th Workshop on Geothermal Reservoir Engineering. Stanford University.
Lepinay, E., & Woods, A. (2024). ‘Controls on the temperature of the produced fluid in a double well ATES system.‘ SSRN.