The United Nations scheme was agreed under the 1997 Kyoto protocol as a key part of the overall strategy to fight global warming. It awards tradeable carbon credits to projects that reduce developing countries' greenhouse gas emissions - such as wind farms.
Links:
[1] http://admin.indiaenvironmentportal.org.in/news/credits-and-debits-how-system-has-fared
[2] http://admin.indiaenvironmentportal.org.in/category/newspaper/financial-times-london
[3] http://admin.indiaenvironmentportal.org.in/category/thesaurus/green-house-gases
[4] http://admin.indiaenvironmentportal.org.in/category/thesaurus/global-warming
[5] http://admin.indiaenvironmentportal.org.in/category/thesaurus/kyoto-protocol
[6] http://admin.indiaenvironmentportal.org.in/category/thesaurus/emission-targets
[7] http://admin.indiaenvironmentportal.org.in/category/thesaurus/un
[8] http://admin.indiaenvironmentportal.org.in/category/thesaurus/developing-countries