Pediaditis et al.: Bilevel Optimization Model for the Design of Distribution Use-of-System Tari sGeneration curtailment at node i and period (t, d) (MWh) π i,t,d Distribution use of system (DUoS) tari at node i and period (t, d) (e/MWh) u i,t,d,n Binary variable of tari level n at node i and period (t, d) P j,t,d Active power ow on branch j and period (t, d) (MW) Q j,t,d Reactive power ow on branch j and period (t, d) (MVar) v i,t,d Square of the voltage at node i and period (t, d) (V 2 )