The client TotalEnergies Renewables International planned to operate and invest in a multi-tenant battery energy storage system (BESS). This approach resembles the principle of an energy cloud storage system. With this objective in mind, the client wanted to assess the regulatory challenges and specifications for the following questions:

• How are the ownership of energy and the metering concept – related to the energy transaction for balancing the portfolio, grid balancing and the provision of ancillary services – regulated?
• What fees, taxes and charges (calculations for certain transactions) are applied?
• Which role is played by green certificates / guarantees of origin with real-time settlement? Are there real-time settlement mechanisms instead of netting?
• Is it feasible for HKN certificates remain with electricity even during storage?
• What formal requirements exist for the implementation of this concept in a multi-client used BESS?

We identified and assessed use and business cases for a multi-client used BESS (principle of cloud storage), which comprise the marketing of the stored energy or storage potential as well as the marketing of the grid-serving operation. Furthermore, we identified and listed regulatory issues from the current and prospective framework and analysed the use cases against the background of the regulatory framework and determined feasible business cases. Within this scope, we assessed which issues can be solved and which issues remain from the regulatory background.

We determined feasible use and business cases for the multi-client capable BESS and demonstrated the granularity optimisation potential. We produced a report that serves as a decision aid for investments or as a starting point for a due diligence process. This final report presented the conclusions with detailed illustrations and key messages.