As their development continues, electric cars remain one of the most popular forms of green transportation currently on the market. However, biogas and methane fuel have been around for some time now have have done a long way towards making their own impact. Frequently coming from the byproduct of farm animals, especially cows, biogas is a cheap and effective alternative fuel source that is already commonly used in some parts of the world.

One airline is advertising that its fleet emits less carbon emissions than a Prius per passenger mile. Obviously there’s more to being “green” than low carbon emissions. But let’s follow this story.