Bioethanol processing from wheat straw: investment appraisal of a full-scale UK biofuel refinery

Abstract

An indicative economic appraisal of a biorefinery investment has been undertaken for the case of an archetypal, full-scale process plant based on bioethanol production from wheat straw: a cellulosic co-product or ‘waste’ stream. A ‘life-cycle’, or ‘through-life’, biofuel chain was examined from the supply of wheat straw, through biochemical conversion processing, and distribution of product to fuel terminals for use in the transport network. The process technology investigated was dilute acid pre-treatment and enzymatic hydrolysis. Discounted cash flow (DCF) investment appraisal formed the key evaluation methodology, and the results were found to depend on the discount rate and lifespan of the biorefinery. Analysis of suitable UK locations, refinery scale or size, and logistics established potential low cost areas with good access to wheat straw. DCF investment appraisals of this type enable industrialists and policy makers to determine the implications of bioethanol production from wheat straw within a low carbon future.