All organisms produce methane

[Meredith Poor + 894]

https://www.mpg.de/18403646/0309-terr-all-organisms-produce-methane-153410-x

Quote

 

As the researchers have now been able to show using the bacterium Bacillus subtilis, there is a close connection between metabolic activity and extent of methane formation. Metabolic activity, especially under the influence of oxygen, leads to the formation of reactive oxygen species in cells, which include hydrogen peroxide and hydroxyl radicals.  In interaction with the essential element iron, the Fenton reaction takes place - a reaction between reduced iron and hydrogen peroxide that leads to the formation of highly reactive tetravalent iron compounds and hydroxyl radicals.

The latter molecules drive the cleavage of a methyl radical from methylated sulfur and nitrogen compounds, e.g., the amino acid methionine. In a subsequent reaction of the methyl radical with a hydrogen atom, methane is finally formed. All reactions can take place under physiological conditions in a test tube and are significantly enhanced by biomolecules such as ATP and NADH, which are generated by cellular metabolism.

 

This is simply a continuation of the proposal that methane is a 'renewable' fuel.

It is also unavoidable - a completely 'green' energy economy would be producing and using vast quantities of methane in one form or another. See in particular the idea of using algae to produce diesel or jet fuel.