An improved system and method of automating the integration of different Energy Management Systems (EMS) electrical power grid databases into a single power grid database. This method imports proprietary EMS raw data from various vendors' formats into a Common Information Model (CIM) with specific connectivity extensions and produces an electrically connected power systems database that can be viewed or edited. Direct network topology conversion from one EMS vendor data format to another is also supported. Two generated databases can then be selectively integrated and maintained to produce a fully populated network topology without disclosing EMS vendor specific proprietary information. The new, possibly larger, database can then be added to yet another database that is similarly processed.