Assessing energy storage technology options using a multi-criteria decision analysis-based framework

With the growing adoption of intermittent renewable energy generation the role for energy storage to provide a number of service needs is being increasingly recognised. However, 'energy storage' encompasses a family of technologies, each with its own set of performance, cost and physical characteristics, at different stages of development. At the same time, each energy system however defined has specific needs; and energy systems are themselves part of a wider socio-technical system which has aims beyond the confines of the energy 'tri-lemma'. As energy storage technologies develop, funding is becoming available to demonstrate their application in realistic environments. However, with multiple technical and non-technical factors to consider, it is challenging for many decision makers who often have limited expertise and resources to select which projects to support. In this paper we first describe a novel framework for assessing the wider benefits that could come from deploying energy storage using Multi-Attribute Value Theory (MAVT), a form of Multi-Criteria Decision Analysis. We then use the framework to assess six potential energy storage projects through a combination of technical analysis and stakeholder input in the county of Cornwall in the UK: a region that has good solar and wind resource with relatively low demand and constrained network infrastructure. The projects assessed were: power to gas, a distributed battery system, battery storage integrated with solar PV and demand from Cornwall Airport Newquay, liquid air energy storage, battery storage integrated with wave energy, and thermal energy storage at a new residential development. We conclude that MAVT can provide a straightforward and user-friendly approach, which can be easily used by decision makers for assessing energy storage projects across a range of criteria and promoting engagement with stakeholders. This approach also allows the subjectivity of decision-making, a potential limitation, to be explored through a sensitivity analysis. The use of MAVT can lead to important insights for the development of energy systems, which in this study included the importance of local priorities to decision-making. In this case, battery storage with PV and demand from Cornwall Airport Newquay was the top-ranking project, performing well across a range of attributes including the maturity of the technology, its ability to defer grid upgrades and economic viability.