Load shedding and demand side management enhancements to improve the security of a national electrical system

In a liberalized and fragmented market, with many operators involved, ancillary services are provided by several actors. Distribution utilities take part in the reduction of the vulnerability of the electrical system in agreement with guidelines and rules stated by Independent System Operators. In Italy, most of emergency defence systems are implemented on HV/MV distribution sub-stations and on MV grids. After the 2003 Italian blackout many projects have been undertaken to improve emergency plans both in medium and long term perspective. In the short term, the collaboration among the Italian ISO and Distribution Companies brought to experiment new equipment and strategies in distribution networks. In the long term, research is focusing also in the exploitation of the use of Electronic Meters to manage peak demand. Even if Demand Side Management (DSM) cannot be properly considered an emergency plan for the security of an electric systems, it could contribute to stabilize it, assuring a sufficient generation margin, through a better use of energy. DSM through AMR can benefit from statistical models for load profile fitting and forecasting. Using a combination of regression and times series models, it is possible to obtain accurate short-term predictions of the load at any load point. Schemes and layouts of local automation systems are presented. Limits are considered.