Addressing the question of regional generation adequacy in capacity expansion planning

Due to an upcoming shift from a power system dominated by dispatchable thermal power plants to a system shaped by renewable energy sources with intermittent feed-in the issue of generation adequacy gains in importance. Despite the European pursuit of a sustainable generation system, the claim for a certain level of security of supply remains which requires investments in new power plants in the long term. Thereby, the question arises whether generation adequacy should be addressed on a national or pan-European level. Thus, this paper evaluates three different interpretations of generation adequacy by optimizing respective least-cost development paths of the European generation stack. The results show that cross-border approaches lead to a reduced amount of new expansion compared to national concepts (-41 GW) while satisfying a comparable level of security of supply.