Author’s Note: This is the second in a two-part series on Renewable Energy Certificates (RECs). In the first post we told the history of REC , its definition and basic purpose. This time, we explore the myriad ways in which RECs are used; impact on the electric grid; role in clean air policy; growth of large scale renewable development; and the REC’s recent resurgence.

Author’s Note: This is a two-part series on Renewable Energy Certificates. In this first posting we discuss what a Renewable Energy Certificate is and the history about how they came into existence. In the next posting, we will discuss some of the additional benefits they bring and why we need to continue using them.

Benjamin Greenberg, Sterling Planet Social Media Manager, attended Atlanta's Ready for 100 Community Conversations and shares his experience as the city begins its work toward 100% clean energy.