[en] After a literature survey enabling the determination of the advantages and drawbacks of existing methods of assessment of the potential energy gains of an industrial site, this research report presents a newly developed method, named Energy and Exergy Analysis of Transformation Processes (or AEEP for Analyse energetique et exergetique des procedes de transformation), while dealing with actual industrial operations, in order to demonstrate the systematic character of this method. The different steps of the method are presented and detailed, one of them, the process analysis, being critical for the application of the developed method. This particular step is then applied to several industrial unitary operations in order to be a base for future energy audits in the concerned industry sectors, as well as to demonstrate its generic and systematic character. The method is the then applied in a global manner to a cheese manufacturing plant, all the different steps of the AEEP being applied. The author demonstrates that AEEP is a systematic method and can be applied to all energy audit levels, moreover to the lowest levels which have a relatively low cost