With growing worldwide awareness of environmental protection, green production has become an important issue for almost every manufacturer and will determine the sustainability of a manufacturer in the long term. A performance evaluation system for green suppliers thus is necessary to determine the suitability of suppliers to cooperate with the firm. While the works on the evaluation and/or selection of suppliers are abundant, those that concern environmental issues are rather limited. Therefore, in this study, a model for evaluating green suppliers is proposed. The Delphi method is applied first to differentiate the criteria for evaluating traditional suppliers and green suppliers. A hierarchy is constructed next to help evaluate the importance of the selected criteria and the performance of green suppliers. Since experts may not identify the importance of factors clearly, the results of questionnaires may be biased. To consider the vagueness of experts’ opinions, the fuzzy extended analytic hierarchy process is exploited. With the proposed model, manufacturers can have a better understanding of the capabilities that a green supplier must possess and can evaluate and select the most suitable green supplier for cooperation.
With increasing government regulation and stronger public awareness in environmental protection, firms today simply cannot ignore environmental issues if they want to survive in the global market. In addition to complying with the environmental regulations for selling products in certain countries, firms need to implement strategies to voluntarily reduce the environmental impacts of their products. The integration of environment, economic and social performances to achieve sustainable development is a major business challenge for the new century (Verghese & Lewis, 2007).
Environmental management is becoming more and more important for corporations as the emphasis on the environmental protection by organizational stakeholders, including stockholders, governments, customers, employees, competitors and communities, keeps increasing. Programs such as design for the environment, life cycle analysis, total quality environmental management, green supply chain management and ISO 14000 standards are popular for environmentally conscious practices (Sarkis, 1998). Both proactive and reactive methods have been implemented to protect the environment. For instance, environmentally conscious design and manufacturing (ECD&M) is a proactive method that aims to reduce the resource consumption, hazardous emission and energy usage by reengineering the design and manufacturing process and selecting appropriate materials (Zhang, 2004). On the other hand, end-of-life (EoL) strategy and management is a reactive method that provides technology and methodologies to handle the wastes which are already present (Zhang, 2004).
As environmental awareness increases, buyers today are learning to purchase goods and services from suppliers that can provide them with low cost, high quality, short lead time, and at the same time, with environmental responsibility. Legislative and regulatory initiatives have also emerged in developed countries, especially in Europe and Japan. Some pioneer enterprises have already joined the trend of green supply chain long before the EU environmental orders were enforced. In order to have a long-term success in the global market, a firm not only should stress on financial terms in evaluating suppliers, but also should take various criteria, including pro-environmental concerns, into consideration. Therefore, green procurement approach must be compliant with customers, laws and regulations, and a green supplier evaluation system is necessary for a firm in determining the suitability of a supplier as a partner in the green supply chain.
The rest of this paper is organized as follows. Section 2 reviews some recent works on environmental management and green supplier evaluation. Analytic hierarchy process (AHP), fuzzy set theory and fuzzy-extended AHP (FAHP) are presented in Section 3. Section 4 proposes a FAHP model applied to evaluate green suppliers. Some concluding remarks are made in the last section.
Environmental protection and sustainable development are getting more and more attention in industry. In order to extend the product life cycle and to pursue enterprise perpetuity, a firm needs to emphasize environment protection and green production as a critical part of its social responsibility. A good green supplier selection model in a dynamic competitive and regulatory environment can help lessen the environmental and legal risks and increase the competitiveness of a firm. This paper proposes a model to select the factors for evaluating green suppliers, and to evaluate the performance of suppliers. The Delphi method is applied first to select the most important sub-criteria for traditional suppliers and for green suppliers. The results for green supplier are applied next to construct a hierarchy for green supplier evaluation problem. A FEAHP model is constructed next based on the hierarchy to evaluate green suppliers for an anonymous TFT–LCD manufacturer in Taiwan, and the most suitable supplier can be selected. The strength of the proposed model is that the vagueness of experts’ opinions is considered in the evaluation process and the model is easy to apply. Manufacturers of related industries can use our proposed model, or tailor the model to meet their own needs, to evaluate their green suppliers or to select the best green supplier for cooperation.