Annual balancing costs in Great Britain ranged from £1 billion to £4 billion over the past six years. The system operator projects that despite efforts to reduce balancing costs, they will remain high, rising to £3- £5 billion a year in 2030. If the network is significantly reinforced by 2030, these annual costs could drop to approximately £2 billion after 2030, which will still be a non-negligible cost. A substantial portion of balancing costs relates to the expenses of resources participating in the balancing mechanism.

To enhance transparency regarding the balancing mechanism, the system operator in Great Britain has initiated the publication of data and supporting information that addresses questions raised by market participants. This paper introduces a novel visualization tool that further improves transparency and can be used for multiple applications. The tool is the only open-source tool that provides spatial awareness of the offers accepted by the balancing mechanism. By assigning each balancing mechanism unit to a specific grid supply point, this novel visualization tool enables users to view balancing mechanism results at different locations across the British electricity network.

The tool is flexibly designed, allowing users to integrate balancing mechanism results from local files or directly from the official website, where they are posted in real time. Additionally, the tool enables the integration of other datasets such as forecasts for variable renewable resources, which can enhance the interpretation of balancing mechanism results. In the tool, the data is presented with a 5-minute resolution, which is particularly valuable for analyzing the participation of flexible resources.

The paper also illustrates a potential use case for the tool involving storage resources participating in the balancing mechanism. This use case shows that the potential revenues for storage resources from the balancing mechanism can vary significantly depending on the grid location. Furthermore, the tool can assist users in estimating historical renewable curtailment costs at multiple locations.

The source code for the tool has been developed as part of a Master thesis and will be publicly available in a repository in June 2025. Intended users include resources participating in the balancing mechanism, interconnectors to the British grid, system operators, and researchers. The tool can also serve as a foundation for further research, especially in the development of digital simulators of the balancing mechanism.