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.