During last years, in Mediterranean and Central Europe area, during warm season, has growth the demand of cooling energy in domestic sector generally satisfied by electrically-driven units; this trend has involved an increase of power generation capacity of electric utilities and a summer peak load of electric energy consumption with the related problem of some electric black-out. This problem has been the driving force to an increasing interest to small scale polygeneration systems fuelled by natural gas. At the Built Environment Control Laboratory of Seconda Universita di Napoli, is running a system based on gas fuelled internal combustion engine coupled with an Air Cooled Water Chiller, ACWC, and a Thermochemical absorption system; the assembly supplies thermal (heating and hot water, 12 kW), electrical (6 kW) and cooling energy (7.5 kW) to a part of a building with offices and laboratories under actual operating conditions; of course the proposed system will satisfy all year around an electric load, while for conditioning purpose it satisfies during cold season the user thermal requirements (heating and hot water) by means an appropriate thermal storage of 1000 It, and during summer season the cooling and hot water requests. This test facility is equipped with measurement systems based on sensors linked to a data acquisition systems, designed and built to evaluate energetic and environmental performances in actual operating condition The paper deals with the applications of this Micro Combined Cooling, Heating and Power systems, or so-called MicroPolygeneration, under real operating condition for mild climate with the aim of evaluating their potential employment in building conditioning systems.