Power Purchasing Agreement in the Framework of Civil Law

Power purchasing agreements (PPA) seek to protect and develop electricity production specifically some kinds like renewable and green electricity. They have been common after restructuring electricity industrial. They now broadly are used as a mean to conservation of environment, electricity security of supply and foreign investment protection around the world. In Iran after restructuring of electricity industrial according to article 25(b) of "fourth development program act,” ministry of power and its company (Tavanir) designed and concluded some type of power purchasing agreements (PPA). These contracts comprise some terms and conditions, which refer to general rules of contract and either technical restrictions. This article seeks to study these contracts terms and conditions in the framework of sale contract and general rules of contract under Iranian civil law. We will answer to this question that these contracts shall be assumed as a sale contract or a specific contract under article 10? It seems to there are not exactly sale contract that has been mentioned in the article 338 and deem to be an especially contract.