Environmental and economic analysis of the fully integrated biorefinery

Abstract

Cellulosic biofuel systems have the potential to significantly reduce the environmental impact of the world's transportation energy requirements. However, realizing this potential will require systems level thinking and scale integration. Until now, we have lacked modeling tools for studying the behavior of integrated cellulosic biofuel systems. In this paper, we describe a new research tool, the Biorefinery and Farm Integration Tool (BFIT) in which the production of fuel ethanol from cellulosic biomass is integrated with crop and animal (agricultural) production models. Uniting these three subsystems in a single combined model has allowed, for the first time, basic environmental and economic analysis of biomass production, possible secondary products, fertilizer production, and bioenergy production across various regions of the United States. Using BFIT, we simulate cellulosic ethanol production embedded in realistic agricultural landscapes in nine locations under a collection of farm management scenarios. This combined modeling approach permits analysis of economic profitability and highlights key areas for environmental improvement. These results show the advantages of introducing integrated biorefinery systems within agricultural landscapes. This is particularly true in the Midwest, which our results suggest is a good setting for the cellulosic ethanol industry. Specifically, results show that inclusion of cellulosic biofuel systems into existing agriculture enhances farm economics and reduces total landscape emissions. Model results also indicate a limited ethanol price effect from increased biomass transportation distance. Sensitivity analysis using BFIT revealed those variables having the strongest effects on the overall system performance, namely: biorefinery size, switchgrass yield, and biomass farm gate price.

Biomass Production a Stronger Driver of Cellulosic Ethanol Yield than Biomass Quality

“…the refinery (Sendich and Dale, 2009). However, transportation costs of low-density herbaceous crops can be prohibitive, so some have pointed to a particular radius around a proposed biorefinery-so-called "fuelsheds"-as the key hectares for biomass supply (Kim and Dale, 2015).…”

Chemical and Physicochemical Pretreatment of Lignocellulosic Biomass: A Review

“…Sendich and coworkers [139, 140] used updated parameters and ammonia recovery configurations in the model of Eggeman and Elander and calculated the cost of ethanol production using AFEX. They found out that the minimum ethanol selling price reduced from $1.41/gal to $0.81/gal.…”

Spatial Analysis of Biomass Resources within a Socio-Ecologically Heterogeneous Region: Identifying Opportunities for a Mixed Feedstock Stream

“…Although energy crops have considerable promise in the region, there is evidence to show that growers will not establish these crops unless there is a guaranteed market while developers will not provide that market without a guaranteed supply [61]. This persistent chicken-and-egg situation, along with the risk aversion of the general farming community with respect to fundamental changes to their target market and their planting-growing-harvesting activities (see [18,62]), means it would be overly optimistic to assume idle land will be allocated toward the production of dedicated energy crops.…”