Battery Energy Storage Systems (BESS) projects are becoming increasingly prevalent. The compact nature of a BESS allows them to be installed in a relatively small footprint, which is ideal for installation close to existing generators, but also in place of old decommissioned generators such as coal fired power stations. In both cases utilising existing transmission infrastructure as a connection point. From an earthing perspective this requires careful consideration of the various transmission fault scenarios, which include multi-source contributions to an earth fault, high fault levels and even analysis of mutual earthing resistance (MER) that will occur during a real fault, where one close source of fault current may contribute to MER, whilst more remote sources may not.
This joint presentation will examine a case study of a BESS earthing system from design challenges (Enerven) through to commissioning testing (Safearth), focusing on how the complexities of the transmission system were considered throughout the earthing design process and how commissioning testing was undertaken in order to assess these complexities. This case study provides an example of looking at the overall picture, analysing and applying it throughout the process.
The presentation will cover both design and testing aspects of the project.