Agro-residues are principally straws from wheat, rice, maize and other cereal crops.
On a worldwide level, it is estimated that potentially 1500 million tons are available. In Europe, straw production is estimated to be approximately 120 million tons (source: FP6 RENEW project), while in Asia, 700 million tons are produced (source: FAOSTAT).
However, the estimation of how much agro-residues can actually be mobilized for biorefining depends on many factors including local climate, crop rotation, existing soil fertility and tillage practices (Kim and Dale 2004). In Europe, about 50% of wheat straw is actually collected, while in Asia a variable proportion is burnt in the field. In Thailand for example 24–40% of annual rice straw production could be available for biorefining (Suramaythangkoor and Gheewala, 2008), while in modern India, increasing amounts (40-60 million tons) are annually available (Prasad et al, 2007; Sarkar, 2007; TERI internal communication).