− | [[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>: |
− | [[Liquefied_Petroleum_Gas_(LPG)|LPG]] is a by-product of extracted natural gas and refined crude oil, with a ratio of 40:60 % respectively. It is a mixture of hydrocarbon gases, with the two most common ones being butane and propane<ref name="Priesemann, C. & Volkmer, H. (2015). Liquefied Petroleum Gas (LPG). Retrieved from: https://energypedia.info/wiki/Liquefied_Petroleum_Gas_(LPG)">Priesemann, C. & Volkmer, H. (2015). Liquefied Petroleum Gas (LPG). Retrieved from: https://energypedia.info/wiki/Liquefied_Petroleum_Gas_(LPG)</ref><ref name="Sepp, S. (2014). Multiple Household Fuel Use – A balance choice between firewood, charcoal and LPG. Retrieved from: https://www.cleancookingalliance.org/binary-data/RESOURCE/file/000/000/287-1.pdf">Sepp, S. (2014). Multiple Household Fuel Use – A balance choice between firewood, charcoal and LPG. Retrieved from: https://www.cleancookingalliance.org/binary-data/RESOURCE/file/000/000/287-1.pdf</ref>. It may also contain small amount of propylene and butylene, in addition to traces of ethane, ethylene, pentane and butadiene<ref name="African Oxygen Limited (AFROX). (2018). 2018 Product Reference Manual, Chapter 5: Liquefied Petroleum Gas (LPG). Retrieved from: http://www.afrox.co.za/en/images/2018%20Product%20Reference%20Manual%20full%20version_tcm266-503458.pdf">African Oxygen Limited (AFROX). (2018). 2018 Product Reference Manual, Chapter 5: Liquefied Petroleum Gas (LPG). Retrieved from: http://www.afrox.co.za/en/images/2018%20Product%20Reference%20Manual%20full%20version_tcm266-503458.pdf</ref>. This combination of hydrocarbons is vaporous, colorless and odorless at standard room temperature and pressure. With modest pressure and cooler conditions, it can be liquefied and stored in cylinders (cylinders are filled with 80% liquid LPG and 20% gaseous LPG for safety reasons)<ref name="African Oxygen Limited (AFROX). (2018). 2018 Product Reference Manual, Chapter 5: Liquefied Petroleum Gas (LPG). Retrieved from: http://www.afrox.co.za/en/images/2018%20Product%20Reference%20Manual%20full%20version_tcm266-503458.pdf">African Oxygen Limited (AFROX). (2018). 2018 Product Reference Manual, Chapter 5: Liquefied Petroleum Gas (LPG). Retrieved from: http://www.afrox.co.za/en/images/2018%20Product%20Reference%20Manual%20full%20version_tcm266-503458.pdf</ref><ref name="Sepp, S. (2014). Multiple Household Fuel Use – A balance choice between firewood, charcoal and LPG. Retrieved from: https://www.cleancookingalliance.org/binary-data/RESOURCE/file/000/000/287-1.pdf">Sepp, S. (2014). Multiple Household Fuel Use – A balance choice between firewood, charcoal and LPG. Retrieved from: https://www.cleancookingalliance.org/binary-data/RESOURCE/file/000/000/287-1.pdf</ref>. This liquid is then transported to the end-users in relatively light cylinders. The consumers can convert the stored liquid into usable gas by opening the cylinder’s valve, which decreases the cylinder’s pressure resulting in the vaporization of the stored liquid<ref name="African Oxygen Limited (AFROX). (2018). 2018 Product Reference Manual, Chapter 5: Liquefied Petroleum Gas (LPG). Retrieved from: http://www.afrox.co.za/en/images/2018%20Product%20Reference%20Manual%20full%20version_tcm266-503458.pdf">African Oxygen Limited (AFROX). (2018). 2018 Product Reference Manual, Chapter 5: Liquefied Petroleum Gas (LPG). Retrieved from: http://www.afrox.co.za/en/images/2018%20Product%20Reference%20Manual%20full%20version_tcm266-503458.pdf</ref>. LPG claims the leading position among energy carriers, when it comes to energy density, combustion efficiency, heat transfer efficiency and heat control characteristics<ref name="Sepp, S. (2014). Multiple Household Fuel Use – A balance choice between firewood, charcoal and LPG. Retrieved from: https://www.cleancookingalliance.org/binary-data/RESOURCE/file/000/000/287-1.pdf">Sepp, S. (2014). Multiple Household Fuel Use – A balance choice between firewood, charcoal and LPG. Retrieved from: https://www.cleancookingalliance.org/binary-data/RESOURCE/file/000/000/287-1.pdf</ref>. LPG has a thermal combustion efficiency of 45% to 60%<ref name="Bruce, N.G. Aunan, K. & Rehfuess E.A. (2017). Liquefied Petroleum Gas as a Clean Cooking Fuel for Developing Countries: Implications for Climate, Forests, and Affordability. Retrieved from: https://www.kfw-entwicklungsbank.de/PDF/Download-Center/Materialien/2017_Nr.7_CleanCooking_Lang.pdf">Bruce, N.G. Aunan, K. & Rehfuess E.A. (2017). Liquefied Petroleum Gas as a Clean Cooking Fuel for Developing Countries: Implications for Climate, Forests, and Affordability. Retrieved from: https://www.kfw-entwicklungsbank.de/PDF/Download-Center/Materialien/2017_Nr.7_CleanCooking_Lang.pdf</ref>. | + | '''[[Liquefied_Petroleum_Gas_(LPG)|LPG]]''' is a by-product of extracted natural gas and refined crude oil, with a ratio of 40:60 % respectively. It is a mixture of hydrocarbon gases, with the two most common ones being butane and propane<ref name="Priesemann, C. & Volkmer, H. (2015). Liquefied Petroleum Gas (LPG). Retrieved from: https://energypedia.info/wiki/Liquefied_Petroleum_Gas_(LPG)">Priesemann, C. & Volkmer, H. (2015). Liquefied Petroleum Gas (LPG). Retrieved from: https://energypedia.info/wiki/Liquefied_Petroleum_Gas_(LPG)</ref><ref name="Sepp, S. (2014). Multiple Household Fuel Use – A balance choice between firewood, charcoal and LPG. Retrieved from: https://www.cleancookingalliance.org/binary-data/RESOURCE/file/000/000/287-1.pdf">Sepp, S. (2014). Multiple Household Fuel Use – A balance choice between firewood, charcoal and LPG. Retrieved from: https://www.cleancookingalliance.org/binary-data/RESOURCE/file/000/000/287-1.pdf</ref>. It may also contain small amount of propylene and butylene, in addition to traces of ethane, ethylene, pentane and butadiene<ref name="African Oxygen Limited (AFROX). (2018). 2018 Product Reference Manual, Chapter 5: Liquefied Petroleum Gas (LPG). Retrieved from: http://www.afrox.co.za/en/images/2018%20Product%20Reference%20Manual%20full%20version_tcm266-503458.pdf">African Oxygen Limited (AFROX). (2018). 2018 Product Reference Manual, Chapter 5: Liquefied Petroleum Gas (LPG). Retrieved from: http://www.afrox.co.za/en/images/2018%20Product%20Reference%20Manual%20full%20version_tcm266-503458.pdf</ref>. This combination of hydrocarbons is vaporous, colorless and odorless at standard room temperature and pressure. With modest pressure and cooler conditions, it can be liquefied and stored in cylinders (cylinders are filled with 80% liquid LPG and 20% gaseous LPG for safety reasons)<ref name="African Oxygen Limited (AFROX). (2018). 2018 Product Reference Manual, Chapter 5: Liquefied Petroleum Gas (LPG). Retrieved from: http://www.afrox.co.za/en/images/2018%20Product%20Reference%20Manual%20full%20version_tcm266-503458.pdf">African Oxygen Limited (AFROX). (2018). 2018 Product Reference Manual, Chapter 5: Liquefied Petroleum Gas (LPG). Retrieved from: http://www.afrox.co.za/en/images/2018%20Product%20Reference%20Manual%20full%20version_tcm266-503458.pdf</ref><ref name="Sepp, S. (2014). Multiple Household Fuel Use – A balance choice between firewood, charcoal and LPG. Retrieved from: https://www.cleancookingalliance.org/binary-data/RESOURCE/file/000/000/287-1.pdf">Sepp, S. (2014). Multiple Household Fuel Use – A balance choice between firewood, charcoal and LPG. Retrieved from: https://www.cleancookingalliance.org/binary-data/RESOURCE/file/000/000/287-1.pdf</ref>. This liquid is then transported to the end-users in relatively light cylinders. The consumers can convert the stored liquid into usable gas by opening the cylinder’s valve, which decreases the cylinder’s pressure resulting in the vaporization of the stored liquid<ref name="African Oxygen Limited (AFROX). (2018). 2018 Product Reference Manual, Chapter 5: Liquefied Petroleum Gas (LPG). Retrieved from: http://www.afrox.co.za/en/images/2018%20Product%20Reference%20Manual%20full%20version_tcm266-503458.pdf">African Oxygen Limited (AFROX). (2018). 2018 Product Reference Manual, Chapter 5: Liquefied Petroleum Gas (LPG). Retrieved from: http://www.afrox.co.za/en/images/2018%20Product%20Reference%20Manual%20full%20version_tcm266-503458.pdf</ref>. LPG claims the leading position among energy carriers, when it comes to energy density, combustion efficiency, heat transfer efficiency and heat control characteristics<ref name="Sepp, S. (2014). Multiple Household Fuel Use – A balance choice between firewood, charcoal and LPG. Retrieved from: https://www.cleancookingalliance.org/binary-data/RESOURCE/file/000/000/287-1.pdf">Sepp, S. (2014). Multiple Household Fuel Use – A balance choice between firewood, charcoal and LPG. Retrieved from: https://www.cleancookingalliance.org/binary-data/RESOURCE/file/000/000/287-1.pdf</ref>. LPG has a thermal combustion efficiency of 45% to 60%<ref name="Bruce, N.G. Aunan, K. & Rehfuess E.A. (2017). Liquefied Petroleum Gas as a Clean Cooking Fuel for Developing Countries: Implications for Climate, Forests, and Affordability. Retrieved from: https://www.kfw-entwicklungsbank.de/PDF/Download-Center/Materialien/2017_Nr.7_CleanCooking_Lang.pdf">Bruce, N.G. Aunan, K. & Rehfuess E.A. (2017). Liquefied Petroleum Gas as a Clean Cooking Fuel for Developing Countries: Implications for Climate, Forests, and Affordability. Retrieved from: https://www.kfw-entwicklungsbank.de/PDF/Download-Center/Materialien/2017_Nr.7_CleanCooking_Lang.pdf</ref>. |