Power Purchase Agreements (PPAs). PPAs are the predominant pathway for cities and utilities to contract for new clean power projects. “How Cities Can Benefit From Power Purchase Agreements” www.c2es.org Sept. ‘18. “Off-Site Physical PPA” www.cityrenewables.org . “How Cities Can Create Demand For Large-scale Clean Energy Generation” www.c40knowledgehub.org . “City of Sacramento Solar PPA” www.gwu.edu