The optimal mix of flexibility in an integrated electricity-hydrogen-heating system: A case study of Great Britain in 2050

Flexibility is crucial in future decarbonised energy systems, compensating for the variability and uncertainty of wind and solar power generation. There already exists a significant amount of flexibility in heat and gas supply systems that can be exploited through the coordinated operation of these energy vectors with the electricity system. However, due to the complex and interdependent interactions between different energy vectors, it is challenging to quantify the amount of flexibility from the other energy vectors available to the electricity system. In this paper, we develop a modelling framework to quantify the amount of flexibility available through energy systems integration, as well as their values to the whole energy system. Using an integrated electricity, hydrogen and heat supply system for Great Britain in 2050 as a case study, the impacts of flexibility on the operational costs of the whole system, locational marginal prices of electricity, and renewable energy curtailment were investigated. The findings illustrated that unlocking whole system's flexibility can achieve over 75% operational cost savings. In addition, we examined relationship between the upward flexibility magnitude and Locational Marginal Prices of the power system and observed a negative correlation between them. This implied that busbars with greater upward flexibility are better positioned to mitigate the impacts of increasing electricity demand.