The use of biogas as a practical measure to protect the climate

The United Nations Framework Convention on Climate Change (UNFCCC) is an international environmental agreement aimed at preventing dangerous human-induced interference with the climate system, slowing global warming and mitigating its consequences.

The 194 countries that are parties to the Convention meet annually at UN Climate Change Conferences (also known as "World Climate Summits"), where they negotiate practical measures to protect the climate. The best-known of these conferences took place in Kyōto, Japan, in 1997 and produced the Kyoto Protocol, which, among other things, established emissions trading.

The agreement, which entered into force on 16 February 2005, set targets binding under international law for the first time for greenhouse gas emissions in industrialised countries. These emissions are the main cause of global warming. By early December 2011, 193 countries and the European Union had ratified the Kyoto Protocol. The USA never joined the Protocol, and Canada announced its withdrawal from the agreement on 13 December 2011.

The Protocol provides for a reduction in annual greenhouse gas emissions from industrialised countries by an average of 5.2% compared with 1990 levels during the first commitment period (2008–2012). No quantified reduction targets are set for emerging economies or developing countries.

The following greenhouse gases are covered by the Kyoto Protocol:

Greenhouse gas                              Global warming potential (GWP)
Carbon dioxide (CO2)                                    1
Methane (CH4)                                            21
Nitrous oxide (N2O)                                          310
Hydrofluorocarbons (HFCs)          140 - 11,700
Perfluorocarbons (PFCs)                            7,000 - 9,200
Sulphur hexafluoride (SF6)                        23,900


The (relative) global warming potential (also known as greenhouse warming potential or GWP), or CO2 equivalent, indicates how much a specified quantity of a greenhouse gas contributes to the greenhouse effect. Carbon dioxide serves as the reference value; the abbreviation is CO2e (for equivalent).

Emission quantities are assessed using the CO2 equivalents of the individual gases and thus weighted according to their global warming potential. This means, for example, that reducing methane emissions by 1 tonne is equivalent to reducing CO2 emissions by 21 tonnes, as both result in a reduction of 21 tonnes of CO2 equivalent. Using organic waste in biogas plants can therefore also make a significant contribution to reducing greenhouse gas emissions.

Through the Clean Development Mechanism (CDM) provided for under the Kyoto Protocol, industrialised countries that have adopted binding emissions targets under the Protocol can establish projects in developing countries that either reduce emissions (e.g. the construction of biogas plants or wind farms) or remove carbon from the atmosphere and store it in sinks (e.g. afforestation).

The project developer is issued with emissions credits corresponding to the quantity of emissions reduced or carbon stored. The CDM is intended to help industrialised countries achieve their emissions targets while supporting sustainable development in the countries hosting the projects.

CDM projects follow the rules of the UN Climate Change Secretariat (UNFCCC) and, upon successful registration as a CDM project, generate emissions credits (Certified Emission Reductions - CERs). These CERs can then be traded through international emissions trading.

Before submission to the UN Climate Change Secretariat, CDM projects are assessed by accredited independent third parties (Designated Operational Entities - DOEs) against the key criteria of additionality, voluntary participation, contribution to sustainability and correct application of approved CDM methodologies.