A Carbon Credit is created when the equivalent of one metric tonne of carbon dioxide is prevented from entering the atmosphere. Internationally known as Certified Emission Reductions, Emission Reduction Units, or Verified Emission Reductions, each carbon credit has a monetary value depending on the type and origin of the emission reduction produced.

For trading purposes, one allowance or CER is considered equivalent to one metric ton of CO2 emissions. These allowances can be sold privately or in the international market at the prevailing market price. These trade and settle internationally and hence allow allowances to be transferred between countries. Each international transfer is validated by the UNFCCC. Each transfer of ownership within the European Union is additionally validated by the European Commission.

Each carbon credit can be traded on the open market, with the current spot rates on the European Unions Emission Trading Scheme averaging 25 Euros per tonne