REGEN-BY-2 will research, design, construct and experiment a first-of-its-kind lab-scale prototype of a recent near-worldwide patented thermodynamic cycle and related plant for the conversion of thermal sources in energy vectors, i.e. electric, heating and-or cooling powers. REGEN-BY-2 can convert (from small to large-scale) any typology of renewable thermal source from low to high-temperature (e.g. solar, aerothermal, geothermal, hydrothermal) including additional thermal sources (e.g. waste heat). The patented thermodynamic cycle is highly efficient as it is constituted by a proper combination of Carnot cycles operating with two-phase fluid circulating in novel two-phase expanders and two-phase compressors. To be successful, these two-phase machines will have to be designed, prototyped and integrated in the REGEN-BY-2 lab-scale prototype. Moreover, the patented technology has large flexibility due to the control of many process parameters, allowing chasing and satisfying the end-users energy demands in a predictable and dispatchable way.