1st, 2nd, 3rd Generation Feedstocks
Bio-based feedstocks are often referred to as 1st, 2nd or 3rd generation. This denotes the development stage and bio resource that they were taken from. 1st generation are taken from food-based crops, 2nd generation use feedstocks not used for human consumption (i.e. biomass), and 3rd generation will move further to non-land based crops, such as algae.