Mathematical modelling of short-term power storage and its use in grid stabilisation

In the coming years, we need to take significant steps to move away from fossil fuel power generation and towards renewable energy sources. However, these steps will come with their own challenges. For many types of renewable energy, the energy sources are highly variable, and the power generation systems have low inertia, making the entire system more sensitive to these fluctuations in supply. A promising way of dealing with this is to smooth power variability using short-term energy storage systems like supercapacitors, flywheels and superconducting magnetic energy storage.
Mathematical modelling promises to be extremely valuable for understanding the strengths and limitations of different energy storage systems and exploring how they are best controlled and used in order to achieve good power quality. In this research project, I will begin by looking at the dynamics of charge storage and release in lithium ion supercapacitors with the aim of developing a quantitative understanding of how aspects of supercapacitor design affect supercapacitor performance. This work will build on existing models of lithium-ion batteries, but with a focus on understanding charge/discharge behaviour on the short timescales that are appropriate for supercapacitors, aligning with the ESPRC research area "Energy Storage". The methods that I will use for this analysis will focus on the mathematical modelling transport, reaction, and deformation in electrodes and electrolytes, aligning with the EPSRC research area on "Continuum Mechanics".
A second aim of my study of supercapacitors will be to develop reduced models that capture the main features of supercapacitor behaviour but that are also simple enough to be easily incorporated into grid-scale modelling. This will lead into the second part of my project, where I will focus on grid-scale systems and explore whether and how short-term energy storage can be used as a tool for grid stabilisation. This is a particularly pressing issue as we move to a low carbon economy and reduce our reliance on turbine-based technologies. The National Grid has announced new technological systems for frequency response including short-term energy storage and are now exploring the use of decommissioned turbines in maintaining inertia within the grid. My work will help to establish whether and how supercapacitors alone (or a combination of short-term energy storage involving supercapacitors, flywheels, and superconducting coils) can be used to maintain grid stability without having to introduce inertia to the system via decommissioned turbines. This closely aligns with the goal of the ESPRC research area "Whole Energy Systems".