Marknadsliberalisering och integrering : studier av den nordiska elmarknaden

This thesis consists of four self-contained papers related to the Nordic electricity market. Paper [I] examine how the reform of the Nordic electricity markets has affected competition in the electric power supply market, Nord Pool. The question is if the common power market has been competitive or if electric power generators have had market power during the period 1996 -2004. Moreover, since there was a stepwise evolution from national markets to a multinational power market, we also ask how the degree of market power has evolved during this integration process. The results show that electric power generators have had a small, but statistically significant, degree of market power during the whole period. However, studying the integration effect, i.e. how the market power has been affected by additional countries joining Nord Pool, it show that the degree of market power has been reduced and finally vanished as the market has expanded and more countries joined the collaboration. Paper [II] analyse how the deregulation of the Swedish electricity market has affected the price of electric power and how the change in electric power price, in turn, has affected consumers’ welfare. The result shows that the change in pricing principle of electric power following the deregulation has increased consumer welfare over the period studied (1996-2006), with welfare gains about 100 SEK per customer per year, indicating a three per cent welfare gain for the average customer. Paper [III] study whether (and to what extent) the multinational electricity market integration has affected the price dynamics at the Nordic power exchange. The results shows that a larger electricity market seems to reduce the probability of sudden price jumps, but also that the effect on volatility seem to depend on the characteristics, i.e. production structure, of the integrated markets. In Paper [IV] a two-stage study is conducted to investigate the extent to which shocks in the demand and supply for electricity translate into price jumps, and the extent to which this process is affected by the prevailing market structure. The main findings from the study is that whether demand and supply shocks translate into price jumps largely depends on the prevailing market structure, i.e. on how far the market works from capacity constraints. A notable feature of the empirical analysis is also that the marginal effects from positive demand and negative supply shocks on the jump probabilities are mostly insignificant and of small magnitude