English: Energy Efficiency Commitment 
Welsh: Ymrwymiad Effeithlonrwydd Ynni
Subject: Amgylchedd
English definition: EEC. A programme encouraging domestic gas and electricity customers to improve energy efficiency.
Welsh definition: YEY. Rhaglen sy'n annog defnyddwyr nwy a thrydan domestig i ddefnyddio ynni'n fwy effeithlon.