Dataset supporting publication: “A novel ROM methodology to support the estimation of the energy savings under the Measurement and Verification protocol” (publication available for download: GEOFIT Zenodo) Datasets resultant from simulation of the integrated system into buildings. Conference paper presented in IBPSA-England Building Simulation and Optimisation Conference 2020 This paper presents a novel Reduced Order grey box Model (ROM) methodology, based on a Resistor-Capacitor (RC) network, which supports the creation of the baseline energy consumption and the estimation of energy savings due to Energy Conservation Measures (ECMs) under the Measurement and Verification protocol. Within this scope, a description of the RC network, including a calculation of the parameters’ needed to execute the ROM, are presented. This ROM methodology is demonstrated on an educational building located in Sant Cugat, Spain as part of the H2020 GEOFIT project. The results presented in this paper demonstrate that the ROM is sufficiently accurate for the creation of the baseline energy consumption and for estimating the energy savings of different ECMs.