“The Electric Industry Law (LIE) defines in its article 3, section VIII, the Clean Energy Certificates (CEL) as that title issued by the Energy Regulatory Commission (the Commission) that accredits the production of a determined amount of energy electricity from Clean Energies and used to meet the requirements associated with the consumption of the Load Centers.”
Source: https://www.gob.mx/cre/articulos/preguntas-frecuentes-sobre-los-certificados-de-energias-limpias