The testing rig for thermal energy storage and hybrid chillers/heat pump is located in CENTROPROVE and was designed to supply the power and temperature levels needed for the operation of low temperature thermal energy storage systems and generally thermally-operated systems. The main components in the testing rig are the hot storage tank, with a volume of 1.5 m3 (1) and the cold storage tank, with a volume of 1 m3 (2). A gas heater (3) and an electric heater (4) provide hot water to the hot storage tank, while a vapour compression chiller (5) cools down the water inside the cold storage tank. Water in the HT circuit of the system is taken directly from the hot water tank, while the temperature levels for the MT and LT circuits are obtained by mixing the water in the two storages through motorised mixing valves controlled with a PID algorithm. Heat transfer fluid in all the circuits is water. All the pipes are thermally insulated and equipped with variable speed pumps. Data from transducers are monitored and recorded using NI hardware and LabVIEW® environment.

The following sensors are used for data measurement:

• Pt100 1/10 DIN and type T thermocouples to measure inlet and outlet temperature in all the hydraulic circuits;

• MVM 0-250 PA magnetic flow meters with ±5% full scale accuracy;

• Electricity meter with class 1 tolerances to measure the electricity consumption of the components (compressor, controllers, pumps, valve motors) in the system.

Services offered.

The testing bench allows the tests of thermally driven systems (namely thermal energy storage systems, adsorption chiller units, heat pumps, hybrid systems) and the definition of a map of performance of the unit, in terms of cooling capacity, thermal COP and electricity consumption as a function of the operating temperatures (i.e. heat source, condensation and evaporation temperatures). In particular, the following ranges can be set:

- HTin: 55-105°C

- MTin: 25-40°C

- LTin: -10 - 20°C