CGM

In practice

In practice the most important distinction is that CGM and CGMESENTSO-E's European profile of CIM - the narrowed format TSOs actually use to exchange grid models across borders. are not the same thing, however similar the names look and however many letters the abbreviations share. CGM is the model - the data set describing the grid. CGMES is the format in which that model is exchanged. You can have a common grid model without saying anything about the file format, and you can support CGMES without taking part in the model collaboration at all. The conflation surfaces in requirement specifications, where "CGM support" sometimes means "can read CGMES files" and sometimes means "can contribute a model into the merge". It is worth establishing which of the two is actually being asked for. For most grid companies and power suppliers this is infrastructure they never touch directly; it is the machinery of the TSOs and the regional coordination centres. But the models are built on CIMCommon Information Model - IEC standard for semantic modeling of the electricity system, the basis for data exchange between TSOs across Europe. and RDFResource Description Framework - W3C standard for describing resources and their relationships as triples, the foundation for semantic web and CIM data exchange in the energy sector., and that experience is the same as the one required to work with grid models in other settings.