Biogas Composition

Biogas is a type of gas produced by the anaerobic digestion of organic matter such as animal waste, plant matter, and sewage sludge. The composition of biogas varies depending on the type of organic matter used, but it typically consists of:

1. Methane - Methane is the primary component of biogas, typically making up between 50% and 75% of the gas.

2. Carbon dioxide - Carbon dioxide is also a significant component of biogas, typically making up between 25% and 50% of the gas.

3. Trace gases - Biogas may also contain trace amounts of other gases such as hydrogen, nitrogen, and sulfur.

Importance of Methane in Biogas

Methane is the most important component of biogas because it is a potent greenhouse gas and a valuable fuel. Methane has a global warming potential that is 28 times greater than carbon dioxide over a 100-year time horizon, meaning that it has a much greater impact on climate change than carbon dioxide. However, when methane is burned as a fuel, it releases carbon dioxide and water vapor, which are much less potent greenhouse gases than methane. This means that using biogas as a fuel can help to reduce greenhouse gas emissions and mitigate climate change.

Conclusion

In conclusion, the correct answer is option 'A' because biogas consists mainly of methane, which typically makes up between 50% and 75% of the gas. Carbon dioxide is also a significant component of biogas, typically making up between 25% and 50% of the gas, but it is not the primary component. Biogas is important because it can be used as a renewable fuel that can help to reduce greenhouse gas emissions and mitigate climate change.