1. Introduction
Woody biomass is an important source of energy and is
currently the most important source of renewable energy in the
world. In 2010 global use of woody biomass for energy was about
3.8 Gm3/year (30 EJ/year), which consisted of 1.9 Gm3/year (16 EJ/
year) for household fuelwood and 1.9 Gm3/year (14 EJ/year) for
large-scale industrial use. 1,2,3 During the same period, world
primary energy consumption was 541 EJ/year and world