RECs and GOs transactions do not entail physical and exclusive delivery of electrical energy from a renewable energy generator to an organization’s facilities (see What is a “green power purchase”?). Therefore, these transactions have no bearing on the emissions physically attributable to an organization’s electricity consumption (i.e., its “carbon footprint”).
An organization’s carbon footprint is an accounting of physically quantifiable GHG emissions (and removals) to and from the atmosphere that result from the entity’s activities within defined boundaries. This quantification is a form of attributional environmental accounting. The purchase of RECs, GOs, as well as other green power contractually-based purchase claims, are not appropriate instruments for attributing GHG emissions that physically result from an organization’s activities. RECs and GOs are financial instruments and neither change nor represent the physical and exclusive delivery of electrical energy to your organization’s facility. Specifically, the use of an indirect (Scope 2) emission factor based on a REC or GO claim is flawed and misleading as part of an organization’s carbon footprint.
So, RECs and GOs are not a sound basis for carbon footprinting (attributional accounting).
 Open letter rejecting the use of contractual emission factors in reporting GHG Protocol Scope 2 emissions (2015). Available here: https://scope2openletter.wordpress.com