October 2, 2019

Biogas – An Untapped Potential Against Global Warming

Biogas – An Untapped Potential Against Global Warming

Humans are increasingly influencing the climate and the earth’s temperature by burning fossil fuels, cutting down rainforests and farming livestock.  This adds enormous amounts of greenhouse gases (GHG) to the atmosphere, increasing the greenhouse effect and global warming.

Mitigating climate change is one of humanity’s defining challenges in the 21st century.  To stabilize the global climate, emissions must be reduced dramatically.  At the 2015 Paris Climate Conference, 196 countries agreed to limit their GHG emissions and set national targets.  Despite this, GHG emissions reached a record high of 53.5 GtCO2e in 2017, an increase of 0.7 GtCO2e compared to 2016.

Global greenhouse gas emission levels for majors’ emitters: UN Environment Emissions Gap Report 2018

The Intergovernmental Panel on Climate Change (IPCC) finds that CO2 emissions from fossil fuel combustion and industrial processes contributed about 78% of total GHG emissions.  This increased from 1970-to 2010, and by a similar percentage from 2000 to 2010 (IPCC:2014).

Biomethane produced from organic waste is molecularly identical to traditional (fossil) natural gas, and so can be widely used without any changes to current infrastructure.  Biomethane is a carbon-negative fuel source and does not contribute to the greenhouse gas emissions.

The World Biogas Association (WBA) published a report on biogas and anaerobic digestion (AD) in July 2019. The report demonstrates that biogas could rapidly reduce the world’s current GHG emissions by a massive 12%.  A key finding of the report is that AD technology, which produces biogas from the treatment of waste, can help to reduce global greenhouse gas (GHG) emissions by 3 290 to 4 360 Mt CO2 eq. – and has enormous growth potential.

The contribution made by biogas from various waste and residues to renewable energy generation is significant, both in terms of energy supply and in terms of potential GHG emission reduction.  Biogas production has no side-effects (for instance land use/land use change, food security).  Digestate remaining from biogas generation can replace 5-7 % of currently in use chemical fertilizer. This amount could fertilize 82 million hectares (ha) of land, equivalent to the combined arable land in Brazil and Indonesia (WBA).

According to the WBA study to achieve the Paris Agreement goals, emissions from energy generation must fall to around 80kg of CO2 per MWh by 2040. This goal can only be met by renewables.  Biogas provides clear means of climate change mitigation!