In December 1997, more than 160 countries met in Japan, with the same objective, reduce greenhouse gas emissions, cause of one of the biggest environmental problems, global warming. In order to reach an acceptable reduction level, limits were proposed for greenhouse gas emissions on developed countries, in agreement with the United Nations Framework Convention on Climate Change (UNFCCC) in 1992. Greenhouse gas emission reductions were stipulated at 5.2% of the emissions registered in 1990. As such, in order for the developed countries to be able to reach this quota the following flexibility mechanisms were created:

▪ The European Emissions Trading Scheme: is an obligatory responsibility program for big GHG emitters among the 25 European Community member countries.

▪ Joint Implementation: functions through projects of developed countries that signed the Kyoto Protocol.

▪ CDM – Clean Development Mechanism: was created to allow the Kyoto Protocol signatory countries to comply with their reduction quotas in their own country or in a developing country, through the purchase of carbon credits generated in emission reduction” projects in countries with no quota to meet in agreement with the Kyoto Protocol. Brazil, at the moment, is regarded as one of the most expressive markets of this mechanism.

▪ Voluntary Market: is a parallel market governed by the United Nations Framework Convention on Climate Change (UNFCCC). This market profile is more flexible, as its rules have not been through the UNFCCC procedure. Its projects have a shorter approval time cycle and there are more available methodologies. As its name suggests this is a voluntary market, and for this reason more buyers are companies, without obligatory reductions, who are committed to social responsibility, and acquire the credits with the objective of compensating their emissions. 

▪ Sanitary Landfills;
▪ Generation of Renewable Energy (hydro, solar, wind, etc.);
▪ Energetic Efficiency;
▪ Substitution of fossil for renewable biomass fuel;
▪ Sewage Treatment Stations;
▪ Destination of confined animal excrement;
▪ Cogeneration (sugar-alcohol plants);
▪ Reforestation.