Cooling with solar electricity Compression refrigeration system for operation with solar current from ET 250 Features - compression refrigeration system for operation with ET 250 photovoltaic modules or with laboratory power supply ET 256.01 - long cooling time due to cold accumulators and insulation - software for controlling and balancing energy flows - dynamic recording of the refrigerant mass flow rate Learning objectives/experiments - supply a compression refrigeration system with current from photovoltaic modules - components of a photovoltaic refrigerating plant - operation of the compressor with changing power available and cooling demand - charge and discharge cold accumulators - coefficient of performance of the refrigerating plant dependent on operating conditions - refrigeration cycle in the log p-h diagram - energy flow balance Specification [1] compression refrigeration system for operation with electricity from ET 250 photovoltaic modules or from laboratory power supply ET 256.01 [2] compression refrigeration system: refrigerant compressor with adjustable speed, insulated refrigeration chamber with evaporator, cold accumulators and cooling load, thermostatic expansion valve and condenser [3] supply with direct current from photovoltaic modules in ET 250 [4] heater to generate a cooling load [5] control unit for temperature-controlled compressor operation [6] rechargeable cold accumulators [7] sensors to capture temperature and pressure [8] refrigerant mass flow rate precisely calculated via GUNT software [9] GUNT software with control functions and data acquisition via USB under Windows 10 [10] refrigerant R513A, GWP: 631 Technical data Compressor - speed: 2000...3500min-1 - refrigeration capacity: approx. 90W at 0/55°C and 2000min-1 - electrical power consumption: approx. 46W at 0/55°C and 2000min-1 Control unit: input voltage range: 10...45V DC Refrigeration chamber: LxWxH: 400x250x500mm Cold accumulators: phase transition: 5...6°C Refrigerant - R513A - GWP: 631 - filling volume: 450g - CO2-equivalent: 0,3t Measuring ranges - temperature: 4x -30...80°C, 3x 0...120°C - pressure: 2x 0...6bar, 2x 0...30bar - current: 0...10A - voltage: 0...60V - flow rate: refrigerant calculated 0...11kg/h 230V, 50Hz, 1 phase LxWxH: 980x400x580mm Weight: approx. 65kg