Abstract
The continuously growing distributed generation and the business potential for demand response are gradually enabling significant provision of flexibility and reserve towards distribution networks. For this reason, transmission and distribution system operators need to coordinate their operation in order to develop efficient market arrangements that can help utilize all the resources capable of providing ancillary services. SmartNet project investigated the potential interaction schemes between network operators, together with the possible new services devoted to the optimal distribution grid management. This paper summarizes the main challenges in simulating complex electricity systems and flexibility markets for three European countries (Italy, Denmark and Spain) in 2030 scenarios. The simulation results are then analyzed using cost-benefit analysis and regulatory conclusions are deduced.