HEAT PUMP
heat Pump  title
Heatpump Component Model
heat Pump  Model overview
Model Overview
Author / organization: Matthildi Apostolou / EDF
Domain: Energy conversion device
Intended application: Optimisation processes
Modelling of spatial aspects: Lumped (single device)
Model dynamics: Quasistatic
Model of computation: To be used by an optimization algorithm
Functional representation: Implicit
heat Pump  input and output
Input and Output
Input variables :
 Real Pdemand: thermal demand (kW)
 Real Tdemand,in: input temperature of the demand (degC))
 Real Tdemand,out: output temperature of the demand (degC)
 Real Psource,max: maximum power of the heat source (kW)
 Real Tsource,in: input temperature of the source (degC)
 Real Tsoure,out : output temperature of the source (degC))
Output variables:
 Real Comp: compressor’s power (kW)
 Real COP: coefficient of performance ()
 Real Cond: condenser’s power (kW)
 Real Evap: evaporator’s power (kW)
 Real Thin: Input temperature for the condenser (degC)
 Real THout: Output temperature for the condenser (degC)
 Real TCin: Input temperature for the evaporator (degC)
 Real TCout: Output temperature for the evaporator (degC)
 Real MH: Heat flow for the condenser (kW/K)
 Real MC: Heat flow for the evaporator (kW/K)
2 Volume Thermal Storage  related documents
heat Pump  description
Short Description
A model of a heat pump, with a variable COP. Intended to be used for optimisation processes. Temporal resolution depends on the component: for daily storage resolution can go up to an hour/minute range; for seasonal storage representative days have to be used.
Equations describing the state of the battery are timecontinuous, while the sensors measuring the realtime status are discrete eventbased. Given a specific heating demand profile and a heating source available at low temperature, this test allows the sizing of a heat pump, in terms of COP and compressor’s power at every time step. The objective function is the minimisation of the total exergy consumed.
In test configuration, the heat pump (coupled with the low temperature heating source) is the only technology that can satisfy the demand. The condenser’s power must therefore be equal to the demand at every time step. The evaporator’s and compressor’s power depending on the COP (temperature levels and power considered), are optimised accordingly.
Present use / development status
The model allows, by considering the 1st and 2nd thermodynamic law, the sizing of the heat pump (compressor’s power installed) and the optimisation of the temperature levels for the condenser and evaporator at each time step.
Media Gallery
HeatPump
Model Details
Domain 
 
Intended application (including scale and resolution)  Intended to be used for optimisation processes. Temporal resolution depends on the component: for daily storage resolution can go up to an hour/minute range; for seasonal storage representative days have to be used.
 
Modelling of spatial aspects 
For each of the two layers of the storage tank, mass and temperature are considered homogeneous.  
Model dynamics 
Thermal equilibrium is assumed at every time step considered.  
Model of computation 
Equations describing the state of the battery are timecontinuous, while the sensors measuring the realtime status are discrete eventbased.  
Functional representation 

Input variables (name, type, unit, description) 
 
Output variables (name, type, unit, description) 
 
Parameters (name, type, unit, description) 
 
Internal variables (name, type, unit, description) 
 
Internal constants (name, type, unit, description)    
Model equations  Governing equations  
1. Cond = MH * (Thin – THout)  
Constitutive equations  
  
Boundary conditions  The system respects a number of constraints regarding its power and temperature levels.  
Optional: graphical representation (schematic diagram, state transition diagram, etc.) 
Model Validation  
Narrative  Given a specific heating demand profile and a heating source available at low temperature, this test allows the sizing of a heat pump, in terms of COP and compressor’s power at every time step.  
Test system configuration 
 
Inputs and parameters 
Pdemand(t) and Psource,max(t) are provided as time series in the attached data file (HP_input.csv in data file EDF_HeatPump_ data.zip).  
Control function    
Initial system state    
Temporal resolution  24 periods are investigated, considering a 1hour step in order to represent a day.  
Evolution of system state  In this configuration, the heat pump (coupled with the low temperature heating source) is the only technology that can satisfy the demand. The condenser’s power must therefore be equal to the demand at every time step. The evaporator’s and compressor’s power depending on the COP (temperature levels and power considered), are optimised accordingly.  
Results 
The resulting compressor’s power and COP are provided as time series in the attached data file (HP_output.csv in data file EDF_HeatPump_data.zip).  
Model harmonization  
Narrative  This analysis uses the same test setup as the one used for model validation (see above).  
Test system configuration  same as model validation setup  
Inputs and parameters  same as model validation setup  
Control function (optional)  same as model validation setup  
Initial system state  same as model validation setup  
Temporal resolution  same as model validation setup  
Evolution of system state  same as model validation setup  
Results  Real Elec = 498.511 kWh: total electrical energy consumed within the 24 hours of optimisation time (integral of Comp) 