This report describes the network analyses and evaluation of the main technical-economic benefits regarding the conversion of a transmission line from HVAC (High Voltage Alternating Current) to HVDC (High Voltage Direct Current) in a realistic case of the Italian electricity system in a 2030 scenario.
The activity has been carried out in collaboration and synergy with the University of Padua as part of a Master’s thesis and started by the definition and development of the electro-energy baseline scenario for 2030.
The scenario selected for the Italian system for the 2030 time horizon is based on the NECP (Integrated National Energy and Climate Plan); in this context, particular attention has been paid to Sicily’s electricity system, focusing the analysis on possible network congestion in 2030 also due to the massive production of electricity from renewable generation sources, especially in the western part of the island. The transmission line selected as a candidate for the potential conversion from HVAC to HVDC is the 220 kV Partanna-Partinico double three-phase circuit.
Identifying 2030 as the starting work point, the static analysis of the Sicilian network via power flow execution with nonlinear models implemented in the DIgSILENT (PowerFactory) tool has allowed identifying the effects of the line conversion from HVAC to HVDC on the system electrical quantities, including voltage and reactive power.
The evaluation of the main technical-economic indices for the HVAC-to-HVDC line conversion has been carried out according to the methodology and with the REMARK+ tool developed by RSE, based on optimization algorithms (OPF, Optimal Power Flow). The results show that the conversion of the Partanna-Partinico line from HVAC to HVDC in a 2030 scenario allows for improving the dispatching of the system, with consequent overall reductions in production costs, CO2 emissions, and network congestion.