A system dynamic model to analyse long-term versus short-term implications of various energy policies within the context of the Nordic electricity market has been developed. The model itself provides a theory of the development of the Nordic electricity market in response to various energy policies, both in the long and the short term. The model includes generation scheduling, demand, price formation, investment decisions, resource availability and to some extent technology progress as endogenous. Thus, explanations of the model behaviour can be found from within the model. As examples of use, the model/modeling concept addresses two important questions on the energy policy agenda. First the marginal CO2-emission controversy has been study...