How much does human waste contribute to climate change?

A 2010 U.N. report suggests that it takes a tremendous amount of energy to process human waste around the globe. Find out ways to reduce this energy cost.

A United Nations Environment Program (UNEP) report released in early December 2010 suggests that human waste – everything from the stuff that we chuck in the garbage to the stuff we flush down the toilet – is taking a tremendous amount of energy globally to process. The report suggests that this energy use is contributing to climate change.

The new UNEP report (pdf) called Waste & Climate Change, claims that, globally, the waste management sector contributes 3-5% of global greenhouse gas emissions. That’s about as much as greenhouse gases as airplanes contribute.

Most experts believe methane emissions from landfills represent the biggest impact on the climate from the waste sector. But waste incineration appears to contribute a significant amount as well.

Assaf Biderman’s electronic trash-tracking follows waste in real time

According to the report, there is also good news. There are now effective ways to capture methane from waste. And we can all help by simply diverting food, garden and paper waste to composting or recycling stations. Doing this could cut greenhouse gas emission by 250kg CO2-equivalent per tonne of municipal solid waste. In other words: a lot.

Why do this, exactly? “Every avenue, every opportunity and every option for cutting greenhouse gases needs to be brought into play if the world is to combat dangerous climate change and set the stage for a transition to a low-carbon, resource-efficient Green Economy urgently needed in the 21st century,” said Achim Steiner, UNEP’s Executive Director and Under Secretary General of the U.N., sharing his thoughts about the 2010 United Nations Environment Program (UNEP) report on the connections between energy use and our own garbage.

Beth Lebwohl