Managing Energy Data Using Fuzzy-Sets

Decision making problems involving multiple sources of information is a key issue in scientific debate. In many cases, the information can be expressed as some form of value, which could be numerical or interval, or it can be represented by linguistic labels. In many situations, decision-makers have to deal with values for qualitative criteria that are often imprecisely defined. The required value and weighting of criteria are usually described in linguistic terms, e.g. “very low”, “medium”, “high”, “fair”, “very high”, etc. It is not easy to precisely quantify the rating assigned to each option and precision-based methods are often not suitable. Decision making methods using fuzzy-sets theory have gradually gained acceptance because of their capabilities in handling the impreciseness that is common in rating alternatives. Fuzzy numbers are used to resolve the ambiguity of the subjective and vague judgments of the human mind. Thus, the rating of alternatives and criteria weighting are described using linguistic terms which can be parameterised by triangular or trapezoidal fuzzy numbers. This paper describes a fuzzy-set approach to manage linguistic and crisp information for the assessment and appraisal of energy projects.