The importance of utility systems in today's biorefineries and a vision for tomorrow

Heat and power systems commonly found in today's corn processing facilities, sugar mills, and pulp and paper mills will be reviewed. We will also examine concepts for biorefineries of the future. We will show that energy ratio, defined as the ratio of renewable energy produced divided by the fossil energy input, can vary widely from near unity to values greater than 12. Renewable-based utility systems combined with low-fossil input agricultural systems lead to high-energy ratios.