An hour-ahead prediction model for heavy-tailed spot prices

We propose an hour-ahead prediction model for electricity prices that capture the heavy tailed behavior that we observe in the hourly spot market in the Ercot (Texas) and the PJM West hub grids. We present a model according to which we separate the price process into a thin-tailed trailing median process and a heavy-tailed residual process whose probability distribution can be approximated by a Cauchy distribution. We show empirical evidence that supports our model.