As I understand it, the bulk compost made by one of our local businesses is produced by using heavy machinery to regularly scoop up and turn the source material and keep it active.
How much fossil fuel tends to be used by the machinery in such an operation to produce, say, 1kg of compost? It would also be helpful to know the scale of the operation (eg in kg/yr output or input) for any particular measurement, as there may be strong economies of scale.
I know there will be a higher environmental impact than just the fuel used, but let's just look at the fuel use aspect for this question.
Related question: Compost yourself or let the city handle the organic waste?