Hourly Electricity Demand in Italian Market

In the existing literature only recently there has been attention to consumer demand for electricity in organized markets. In this paper we assume a theoretical model of demand behavior and we estimate a complete system for hourly electricity demand. We use individual demand bid data in the Italian Power Exchange (IPEX). The novel contribution of this paper is twofold. Firstly we construct a theory based behavioral model of hourly electricity demand for agents acting in the Italian market; secondly we measure empirically demand behavior at hourly level, i.e. expenditure and price elasticities directly from consumer behavior. Econometric estimation of a multi-stage demand system weakly separable allows us to identify three robust results, showing that: (i) own price elasticity varies significantly with time of the day as well as according to the level of equilibrium price, (ii) hourly electricity demand exhibits both complementarity and substitutability characteristics, (iii) unconditional elasticity values are different from conditional ones, thus confirming validity of multistage model. On the basis of econometric estimations we can ascertain that elasticity tends to be generally higher when hourly price peak. Considering price elasticity, electricity exhibits both substitutability and complementarity characteristic in different hours of the day, the former during the day and the latter during the night. Considering expenditure elasticity, electricity appears to be a normal good during night time and a luxury good during day time. Policy implications are interesting, because appropriate regulation can favor consumer behavior adjustment shaving consumption away from peak prices, thus yielding lower aggregate equilibrium expenditures because consumers can shift more easily their consumption from peak price hours to off peak price. So we advocate reforming the actual dual administered price structure to introduce real time pricing options for Italian consumers.