Does Biogas Contribute to Climate Change?

The term “climate change” refers to a change in the statistical distribution of weather patterns. Climate change is caused by a number of factors. These can be naturally-occurring factors, such as volcanic eruptions among them or can also be linked to human activities, such as large-scale fossil fuel consumption.

Like fossil fuels, biogas is combustible. It is formed when microbial organic matter degrades in anaerobic conditions, and can be harvested from covered lagoons, landfill sites and enclosed tanks called “anaerobic digesters”. Often made from sludge or animal manures rich in carbohydrates, proteins and lipids, biogas contains a cocktail of methane and carbon monoxide as well as some trace gases.

Although the combustion of biogas produces carbon dioxide, which has been shown to contribute to climate change, all of the carbon present in biogas comes from organic materials, which, in turn, exploited carbon occurring naturally in the atmosphere. Therefore, biogas represents a carbon-neutral fuel source, and does not contribute to climate change.

What is biogas used for?

Biogas is unusually rich in methane. Methane is also the principal component in the fossil fuel natural gas, which is used in the creation of electricity. Scientists have suggested that biogas could replace natural gas in future, enabling carbon-neutral cooking, heating, lighting and electrical generation. Biogas may also become a pipeline gas and a vehicular fuel in years to come.

Further to this, biogas production has been shown to have a less polluting effect on wastewater. Valuable nutrients, such as nitrogen and prosperous, are conserved when biogas is produced, meaning biogas effluents can be converted into saleable crop fertiliser.

What are the barriers to mainstream biogas use? 

According to the American Biogas Council (ABC), the USA has over 2,200 sites producing biogas, although many opportunities for biogas production are not being fully exploited. Until fairly recently, the relatively low cost of fossil fuels dis-incentivised those seeking more environmentally-friendly alternatives.

Today, the price of producing biogas is comparable with the price of producing natural gas. Naturally, greater research, investment and education are helping to turn the tide in favour of biogas. Recently, Blue Mountain Biogas Power Generation plant in Beaver County came on stream. Developed and operated by Alpental Energy Partners of Provo, Utah, the $17 million, 3.2Mw plant will generate electricity from methane gas provided by the anaerobic digestion of swine manure. To read more about this event, read: Blue Mountain Biogas Plant Turns Pig Manure into Power.

Is biogas the future?

Biogas may well represent one of our most important weapons in the fight against climate change. As interest in carbon-neutral and renewable energy soars, more and more people are looking to sustainable energy sources, such as biogas. However, greater research and investment into biogas producing technologies is still required. Until big business gets the biogas bug, it’s unlikely that our domestic applications will be powered by biogas. Yet as fossil fuels dwindle and prices soar, economically and ecologically motivated individuals are being forced to assess the pros and cons of this carbon neutral fuel. 

Can I make biogas myself?

Biogas can be produced at home from food and garden waste. A typical home could cook for an hour each day using homemade biogas.