Resumen
The meaning and significance of medium-term marginal costs for a generation company in a competitive power market in analysed. A methodology to computer and decompose medium-term generation marginal costs in a competitive environment is proposed. The methodology is based on a market equilibrium model. The aim is to provide a useful tool for generation companies so that they can manage their resources in an optimal way, helping them with their operation, decision-making processes, asset valuations or contract assessments.