The system has been designed to combine all the advantages of a micro gas turbine with the opportunity to exploit different energy sources as, for instance, biomass burner or solar concentrator. The use of an external boiler allows to obtain the thermal energy required to operate the gas turbine from the combustion of different sources of biomass (wood, forest waste, animal manure, sewage sludge, etc.) The final system is therefore essentially composed by an external boiler(*) that uses a high-temperature heat exchanger(*) to transfer the thermal energy to a micro gas turbine, that operates in an open “Brayton” cycle. Due to the split-up between combustion and evolving fluid (air), this system allows the use of solid fuels/waste fuels otherwise not usable in small size plants based on gas turbines.