Authors emphasize that price is significant and demand inelastic only for Region 1; the 24 Region-1 hourly elasticities (~ -0.38 to -0.58) are the headline results. || 'the relative price of electricity has the expected negative sign for both regions; however, only for Region 1 is the variable statistically significant. The implied price elasticity of the demand for electricity is inelastic' (p.242)
Cargill, T.E. and R.A. Meyer (1971): “Estimating the Demand for Electricity by Time of Day.” Applied Economics 3(4), 233-246