A characteristic common to every power system is the need to balance the energy demand and the electricity supplied. In order to guarantee this balance, a dedicated market, the Ancillary Services Market, is run to ensure the continuity and security of the system. Today, these regulation services are mainly supplied by large fossil-fuel power plants, but with the diffusion of renewable resources and the decarbonisation of the energy production, new regulation service resources will be required. Hence, in the last years an opening process of the ancillary services market to distributed resources has been launched. In agreement with the Italian Regulatory Authority for Energy, Networks and Environment (ARERA), some pilot projects, aimed at measuring the performance of these resources, have been defined.