The paper focuses on the role of simulation within the RSB GHG Tool, which is a web-based decision support tool that assesses greenhouse gas emissions of biofuels according to the principles of the Roundtable on Sustainable Biofuels. Using a questionnaire, each operator can specify his individual data and calculate the GHG emission for his production step. To derive the environmental flows required for the impact assessment, the tool applies simulation, which allows generating a full inventory on the basis of the limited input data the operator can provide. This is the basis for the interactive assessment of the GHG emissions of individual steps of biofuels pathways, without the need of conducting a time and resource-intensive Life Cycle Assessment study. In this paper, we focus on the simulation for the emissions caused by land use change since such emissions can play a dominating role in the GHG balance of a biofuel.

This paper attempts to highlight shortcomings in the concept of sustainability and ways to make the concept more workable by presenting the development of an Environmental Management Information System (EMIS) as a combination of discrete event simulation and ecological material flow analysis for production processes. The motivation behind the focus on simulation techniques on one hand and on production processes on the other, is the understanding that the current metabolic rates of today's economies are beginning to affect the life-sustaining services of the earth. Dematerialization and resource efficiency are mandatory concepts in the coming decades, hence the production processes; simulation techniques are needed as existing systems cannot be easily changed to be experimented with. There is however a lack of simulation systems addressing sustainability as a whole. This paper intends to show ways on how to connect supposedly opposite factors and thus getting closer to the so called immeasurable: sustainability.