| [[Biogas|Biogas]] is produced by the anaerobic digestion of organic materials such as manure, sewage sludge, organic waste from households, industry waste, and also energy crops. It is composed mainly of methane (40-70%) and carbon dioxide (30-60%)<ref name="“Cooking with Biogas - energypedia.info.” [Online]. Available: https://energypedia.info/wiki/Cooking_with_Biogas. [Accessed: 08-Apr-2019]">“Cooking with Biogas - energypedia.info.” [Online]. Available: https://energypedia.info/wiki/Cooking_with_Biogas. [Accessed: 08-Apr-2019]</ref>. However, it also contains small traces of other compounds such as hydrogen sulphide, nitrogen, hydrogen, methylmercaptans and oxygen <ref name="“Biogas Basics - energypedia.info.” [Online]. Available: https://energypedia.info/wiki/Biogas_Basics. [Accessed: 03-Apr-2019].">“Biogas Basics - energypedia.info.” [Online]. Available: https://energypedia.info/wiki/Biogas_Basics. [Accessed: 03-Apr-2019].</ref>. The energy content of the biogas is directly proportional to the methane content in the biogas (higher methane content is equivalent to higher energy output) <ref name="A. Petersson and A. Wellinger, “Biogas upgrading technologies – developments and innovations,” p. 20.">A. Petersson and A. Wellinger, “Biogas upgrading technologies – developments and innovations,” p. 20.</ref>. 1 m3 of purified biogas contains 6.5 KW of energy and is equivalent to the following fuels <ref name="“Cooking with Biogas - energypedia.info.” [Online]. Available: https://energypedia.info/wiki/Cooking_with_Biogas. [Accessed: 08-Apr-2019]">“Cooking with Biogas - energypedia.info.” [Online]. Available: https://energypedia.info/wiki/Cooking_with_Biogas. [Accessed: 08-Apr-2019]</ref> <ref name="J. van Hessen, “An Assessment of Small-Scale Biodigester Programmes in the Developing World: The SNV and Hivos Approach,” p. 51.">J. van Hessen, “An Assessment of Small-Scale Biodigester Programmes in the Developing World: The SNV and Hivos Approach,” p. 51.</ref> <ref name="RENA, “Measuring small-scale biogas capacity and production,” /publications/2016/Dec/Measuring-small-scale-biogas-capacity-and-production. [Online]. Available: /publications/2016/Dec/Measuring-small-scale-biogas-capacity-and-production. [Accessed: 08-Apr-2019].">RENA, “Measuring small-scale biogas capacity and production,” /publications/2016/Dec/Measuring-small-scale-biogas-capacity-and-production. [Online]. Available: /publications/2016/Dec/Measuring-small-scale-biogas-capacity-and-production. [Accessed: 08-Apr-2019].</ref>: | | [[Biogas|Biogas]] is produced by the anaerobic digestion of organic materials such as manure, sewage sludge, organic waste from households, industry waste, and also energy crops. It is composed mainly of methane (40-70%) and carbon dioxide (30-60%)<ref name="“Cooking with Biogas - energypedia.info.” [Online]. Available: https://energypedia.info/wiki/Cooking_with_Biogas. [Accessed: 08-Apr-2019]">“Cooking with Biogas - energypedia.info.” [Online]. Available: https://energypedia.info/wiki/Cooking_with_Biogas. [Accessed: 08-Apr-2019]</ref>. However, it also contains small traces of other compounds such as hydrogen sulphide, nitrogen, hydrogen, methylmercaptans and oxygen <ref name="“Biogas Basics - energypedia.info.” [Online]. Available: https://energypedia.info/wiki/Biogas_Basics. [Accessed: 03-Apr-2019].">“Biogas Basics - energypedia.info.” [Online]. Available: https://energypedia.info/wiki/Biogas_Basics. [Accessed: 03-Apr-2019].</ref>. The energy content of the biogas is directly proportional to the methane content in the biogas (higher methane content is equivalent to higher energy output) <ref name="A. Petersson and A. Wellinger, “Biogas upgrading technologies – developments and innovations,” p. 20.">A. Petersson and A. Wellinger, “Biogas upgrading technologies – developments and innovations,” p. 20.</ref>. 1 m3 of purified biogas contains 6.5 KW of energy and is equivalent to the following fuels <ref name="“Cooking with Biogas - energypedia.info.” [Online]. Available: https://energypedia.info/wiki/Cooking_with_Biogas. [Accessed: 08-Apr-2019]">“Cooking with Biogas - energypedia.info.” [Online]. Available: https://energypedia.info/wiki/Cooking_with_Biogas. [Accessed: 08-Apr-2019]</ref> <ref name="J. van Hessen, “An Assessment of Small-Scale Biodigester Programmes in the Developing World: The SNV and Hivos Approach,” p. 51.">J. van Hessen, “An Assessment of Small-Scale Biodigester Programmes in the Developing World: The SNV and Hivos Approach,” p. 51.</ref> <ref name="RENA, “Measuring small-scale biogas capacity and production,” /publications/2016/Dec/Measuring-small-scale-biogas-capacity-and-production. [Online]. Available: /publications/2016/Dec/Measuring-small-scale-biogas-capacity-and-production. [Accessed: 08-Apr-2019].">RENA, “Measuring small-scale biogas capacity and production,” /publications/2016/Dec/Measuring-small-scale-biogas-capacity-and-production. [Online]. Available: /publications/2016/Dec/Measuring-small-scale-biogas-capacity-and-production. [Accessed: 08-Apr-2019].</ref>: |