Reporter Andy Revkin reminds us about methane – an important, under-used fuel resource in Africa and elsewhere – in his May 29 New York Times blog Dot Earth.
His discussion of environmental problems associated with charcoal, more commonly used in African nations as a source of fuel, is well rounded. Because of charcoal's problems, he questions why natural gas is abundant yet not widely harnessed on the continent.
Natural gas is primarily made up of methane, a fairly clean burning, but powerful greenhouse gas. However, Mr. Revkin's discussion of methane’s inter-relationship with climate change comes up short in two very important ways.
He asks why “discussions of ways to limit global warming seem more focused on capturing stray emissions of methane.” It is because methane is a greenhouse gas that is 20 times more potent than carbon dioxide.
For each methane molecule burned as fuel, one water molecule and one carbon dioxide molecule is emitted. This means that using captured stray methane emissions as a fuel would have the additional benefit of reducing the human contribution to climate change by a factor of 20.
The primary source of “stray emissions of methane” was also overlooked. Methane is a by-product of agricultural animals. Countries that are industrializing are the fastest growing countries, and their people are eating more meat per day than ever before.
From this, methane emission levels are expected to grow exponentially in the coming years. Using methane emitted from farm animals as a fuel would be a value added to farming without disrupting the food supply.
