Capacity mechanisms in imperfect electricity markets

摘要

This special issue of Utilities Policy is focused on the capacity mechanisms which can complement electricity market designs in order to guarantee sufficient capacities to supply the aggregated electrical demand and energy requirements of costumers at all times. In "energy-only" markets, under scarcity conditions prices for energy and ancillary services would be supposed to rise to clear the market consistent with maintaining system reliability. In fact these prices do not rise fast enough and high enough to pay all the costs of new equipments, and in particular the peaking units, which are necessary to reach an adequate capacity of the system. In response to concerns to create conditions of maintaining system reliability in the long run, a number of adjustments to the market design have been proposed and experimented for stabilizing investment in generating capacity. One decade after, lessons can be drawn from experiments and theoretical debates on the issue of capacity adequacy of liberalised electricity systems.