Fuzzy set-based decision support system for transactions of electricity in a deregulated environment

The authors present a model to evaluate electricity supply contracts for retail consumers who have a choice of retail offers under a recently deregulated environment. A bilateral contract to supply power at a fixed price will be attractive to some consumers, because the spot price in a power exchange market may go up unreasonably. In this approach, uncertain market prices are first estimated by an extended time-series model that considers the possible ranges of prices. Next, an index is introduced to reflect the consumer´s preference for a low price with some margins. The differences in the offered price for a supply contract and the market price estimates are then compared with the preference index. The overall grade of matching the price differential and the consumer´s preference indicates the degree of consumer satisfaction by the offered price for the transaction. Numerical examples using California Power Exchange data are illustrated