An Energy Attribute Certificate (EAC) is a category of contractual instruments used in the energy sector to convey information about energy generation to other entities involved in the sale, distribution, consumption or regulation of electricity. 1 EAC = 1 MWh of renewable electricity. EACs are issued to renewable electricity generators operating within the same market boundary as the claimant. EACs exist in markets with reliable tracking systems to ensure that no double counting of the attributes takes place. Where certificates are purchased directly, and certification programs are not used or available, the exclusive claim of those attributes must otherwise be verified.
RE100, RE100 FAQs, http://there100.org/faqs, 11.11.2019