A consumer decision-making aid for electricity purchases by possibility regression and fuzzy decision

Introduces a decision-making aid for retail consumers of electricity who now have a choice of bilateral transactions and market-based purchases under the recent deregulated environment. Direct transactions between a supplier and the consumer may become attractive in some situations because of a fixed price, while in a power exchange market, gaming and speculation by participants may push up electricity prices unacceptably. In this approach, uncertain market prices are represented by a set of fuzzy numbers containing the highest/lowest price range in a time series. The consumer´s somewhat vague preferences are also defined by a separate fuzzy set. The differences in the offered price for a bilateral contract and the market prices are compared with a preference index. The overall grade of matching the price differential and the consumer´s preference indicates the value of the offered price for the bilateral transaction. Numerical examples illustrate the procedure of this approach