First package of CGMM implementation tasks completed
Earlier this year, “All TSOs” approved the Common Grid Model Methodology (CGMM) as well as the Generation and Load Data Provision Methodology (GLDPM) for submission to national regulatory authorities (NRAs) as required by Regulation 2015/1222 (the CACM Guideline). The NRAs’ review of the methodologies is still ongoing as of the beginning of November 2016.
In the same way in which the Network Codes and Guidelines require material that is too technical or detailed for the Network Codes proper to be covered in methodologies, the methodologies can set out additional “implementation tasks” that cannot be addressed in the methodologies themselves:
Thus both the CGMM and the GLDPM contain a number of such implementation tasks (to be completed within certain deadlines also stated in these methodologies by each TSO individually or ENTSO-E or “All TSOs” jointly). The first package of CGMM implementation tasks has now been completed; “All TSOs” approved a number of documents explained in more detail below.
Common Grid Model Alignment Methodology (CGMAM)
First of all, note that the CGMAM is not a methodology in the legal sense – it is not required by the CACM Regulation and does not need to be approved by NRAs. It is also not written as if it were an EU Regulation. As for the subject matter, note that when building their individual grid models (IGMs) as input for the common grid model (CGM), TSOs have to use a consistent set of balanced net positions and balanced flows on DC lines. Otherwise the load flow calculation will not converge and it would not be possible to build a (usable) CGM. For those target time horizons for which market schedules are available (day-ahead and intraday) the schedules provide the information required. However, for some target time horizons, notably
(D-2) and (Y-1), schedules are not available. The CGMAM makes it possible to provide TSOs with a set of balanced net positions and balanced flows on DC lines even for those target time horizons for which market schedules are not available. The CGMM sets out a number of specific requirements for the CGMAM which have been transposed into the document approved by “All TSOs”:
Quality criteria for individual grid models (IGMs) and common grid models (CGMs)
The CGMM requires TSOs to define quality criteria for both IGMs and CGMs. Both of these tasks are addressed in the document “Quality of CGMES Datasets and Calculations” approved by “All TSOs”.
Requirements applicable to merging agents and the merging process
One further task that the CGMM addresses to “All TSOs” is to formulate the requirements applicable to merging agents and the merging process. The principal document in this respect is the European Merging Function Requirements Specification. However, the document “Migration Process from UCTE DEF to CGMES” constitutes an important addendum. Both documents have now been approved by “All TSOs”.
The ENTSO-E website will be updated as additional CGMM and GLDPM implementation tasks are completed.