The acquisition of Renewable Energy Certificates remains the preferred option of large corporations with sustainability targets to account for zero carbon and operate with 100% renewable energy, according to data from the Global Renewable Energy Program 100 (RE100), as can be seen in figure Unbundleb energy attribute certificate purchase. However, the world market is moving towards a model of energy contract known as “PPA Green”, in which physical energy is sold along with the Renewable Energy Certificate, because only in this way can it be documented to source the energy and ensure traceability, and facilitate the zero-carbon accounting for the energy product.