AERC

The Attachments Energy Rating Council (AERC) is an independent, public interest, non-profit organization whose mission is to provide consumers with credible, relevant, and comparable information about window attachments and their performance.  The AERC is comprised of a diverse group of window attachment manufacturers, component manufacturers, public interest organizations, and utilities who are working together to deliver a successful energy rating program for the window attachment industry.  

https://aercnet.org/