Technoeconomic analysis of wheat straw densification in the Canadian Prairie Province of Manitoba

Abstract

This study presents a technoeconomic analysis of wheat straw densification in Canada’s prairie province of Manitoba as an integral part of biomass-to-cellulosic-ethanol infrastructure. Costs of wheat straw bale and pellet transportation and densification are analysed, including densification plant profitability. Wheat straw collection radius increases nonlinearly with pellet plant capacity, from 9.2 to 37km for a 2–35tonnesh−1 plant. Bales are cheaper under 250km, beyond which the cheapest feedstocks are pellets from the largest pellet plant that can be built to exploit economies of scale. Feedstocks account for the largest percentage of variable costs. Marginal and average cost curves suggest Manitoba could support a pellet plant up to 35tonnesh−1. Operating below capacity (75–50%) significantly erodes a plant’s net present value (NPV). Smaller plants require higher NPV break-even prices. Very large plants have considerable risk under low pellet prices and increased processing costs.