Influence of energy mix on the future grid integration of PV and wind in Europe

Low correlation between renewable energy feed-in and demand has the potential to cause an energy surplus during periods of low loading. In the event of insufficient line capacity for the export of surplus energy, renewable generators must be curtailed. This represents a significant challenge for power system planning, particularly in the context of the expected large-scale deployment of PV and wind generators in the future European power system. The grid integration requirements for renewable generation may be gauged according to both the level of transmission line capacity utilization and the amount of resulting feed-in curtailment. Both of these measures may be reduced through the minimization of the magnitude and frequency of local energy surplus occurrence. Since both PV and wind generation exhibit varying degrees of correlation with demand and with one another, the choice of energy mix plays an important role in the minimization of surplus power generation and avoidance of transmission line congestion. Hence, investigation of the influence that the energy mix has upon the grid integration requirements for PV and wind in the future European transmission system forms the central research objective of this paper.