Renewable Energy Certificates (RECs) are a market-based instrument that certifies the bearer owns one megawatt-hour (MWh) of electricity generated from a renewable energy resource. Once the power provider has fed the energy into the grid, the REC received can then be sold on the open market as an energy commodity. RECs earned may be sold, for example, to other entities that are polluting as a carbon credit to offset their emissions. RECs can go by other names, including Green Tags, Tradable Renewable Certificates (TRCs), Renewable Electricity Certificates, or Renewable Energy Credits.