How can organizations verify how much of their electricity comes from renewable sources, and how are green energy certificates audited to prevent duplication?

To know how much of your electricity use comes from renewable sources, you need to look at whether your electricity is backed by Energy Attribute Certificates (EACs) such as GOs, RECs, or I-RECs. These certificates track the renewable origin of electricity, since once power enters the grid, you can’t distinguish between renewable and conventional sources physically.

The only way to prove renewable use is by owning and retiring EACs that match your consumption. Your electricity supplier may do this for you — or you may need to purchase them separately. Either way, these certificates are issued and tracked in national or international registries, and once retired, they cannot be reused or double-counted.

These registries are audited and regulated, and there are strict rules to avoid duplication. For example, in Europe, the Association of Issuing Bodies oversees the GO system; in North America, similar oversight exists for RECs through regional registries.