Simulation of Manufacturing Enterprises for Sustainability

Simulation technology has been a significant tool for improving manufacturing operations in the past; but its focus has been on lowering costs, improving productivity and quality, and reducing time to market for new products.  In the future, it could similarly help us to achieve green, environmentally friendly or sustainable manufacturing. Changes will need to occur if simulation is to be applied successfully to sustainability. Manufacturers will need to focus on issues that they have not been concerned with in the past. New technologies and standards will be needed to model sustainable manufacturing systems.  This project focuses on the application of systems dynamics modeling, a simulation technology that has not been traditionally used by manufacturing, to sustainable manufacturing.

Environmental regulations, consumer pressures, and increasing cost of resources, especially energy, are forcing many manufacturing firms to make sustainability a major strategic priority.Companies are going "green"by developing environmentally friendly products and converting to clean manufacturing processes that minimize use of materials, hazardous chemicals, and energy. The green approach also emphasizes reuse and recycling.  Simulation modeling methods and technologies may be used to help companies in their sustainability analysis and decision-making processes.

The focus of our research is the application of system dynamics modeling (a form of continuous simulation) to sustainable manufacturing systems analysis. System dynamics may be more appropriate and effective approach to this problem than discrete event simulation. It can be used to develop a better understanding of complex systems, such as business operations, economic and mechanical systems.  System dynamics supports the modeling of systems at aggregate or macro level for strategic decision-making.

System dynamics modeling was created and developed by researchers led by Forrester at the Sloan School of Management at MIT in the late 1950s. A number of system dynamics modeling applications are currently available in the market that can be used to facilitate the modeling process. Models may be developed to investigate particular factor related to manufacturing such as water use, energy consumption, materials usage and pollution, product production, financial costs, etc.   

The NIST modeling and simulation team has had considerable experience with a wide variety of simulation technologies and standards. This project will investigate the creation of layered system dynamics models that represent the different types of manufacturing facilities and operations, related systems, and sustainability factors of interest. We intend to extend traditional models such that connections may be established between interacting elements in different layers of the model. Some of the systems and associated factors that will be modeled include:

• Water – consumption, pollution
• Financial – costs, revenue
• Production – processes, rates
• Transportation – alternatives, delays, commuting
• Labor/community – skills, safety hazards, noise pollution
• Energy – consumption, renewable alternatives
• Atmosphere – pollution
• Terrain/mining – pollution, resource consumption
• Ecology/farms – pollution, filtration, capturing emissions

Ultimately standards will be needed for modeling and simulation methodologies, system architectures, data formats and test data sets. NIST can play a key role in helping to develop those standards. We will develop a framework that can be used to determine the environmental, financial, and profitability effects and interactions of different sustainability policies. Additionally, the research will provide foundation for the evaluation and/or establishment of manufacturing sustainability requirements, regulations, and operating policies.