Abstract

This article presents a study of the techno-economical feasibility of manufacturing biofuel ethanol at small scale from agricultural sources in New Zealand. It investigates possible agricultural products and wastes as potential feedstock and looks at laboratory-scale fermentation trials to determine their ethanol yields. The ethanol requirement to replace all gasoline in New Zealand with a 10 vol% blend (E10) is 300 ML/yr. Current production is derived from whey with output being about one sixth of this requirement. Sugarcane, sugar beets, maize, potato waste, and spoilt kiwifruit possess potential for use as feedstock. New Zealand currently grows approximately 150,000 t/yr maize, sufficient for making 45 ML/yr ethanol, and also has the potential to exploit 100,000 t/yr potato processing waste and 18,000 t/yr spoilt kiwifruit. Sugarcane and sugar beets are currently not grown on a large scale in New Zealand. However, sugarcane is of particular interest because of its high ethanol yield (7,750 L/ha) and ease of processing.