How do RECs work?
Electrons enter the electricity grid from many different sources, including renewables (such as wind and solar power), fossil fuels (such as natural gas or coal), and nuclear. Because of this, there is no way to know exactly what energy source your electricity comes from, and companies located in areas with a high density of wind or solar electricity generation have no more right to claim this renewable electricity than any other company on the grid.
In order to create a market incentive for the procurement of renewables, the ‘attributes’ of the electricity (e.g. how and where it was generated) are sold separately to the electricity itself. This is fundamentally how renewable electricity markets operate in all parts of the globe.