Add extra functionality efficiency class

CHANGELOG.md

@@ -10,6 +10,8 @@ The format is based on [Keep a Changelog](https://keepachangelog.com/en/1.0.0/).
 ### Added
 
 - Add flow_rates as explicit argument in PressureDrop curve function.
+- Add function for cascading heat pumps.
+- Added _get_max_power functions to BuildingLoad classes.
 - Inlet and outlet water temperature (issue #271).
 - Added 'type' attribute to temperature profile plotting so also the inlet and outlet temperatures can be shown (issue
   #271).

GHEtool/Borefield.py

@@ -2012,19 +2012,17 @@ def get_rb(temperature, limit=None, power=None):
                                    hourly_load) / self.number_of_boreholes / H)
                 if not self.borehole.use_constant_Rb:
                     results._Tf_inlet, results._Tf_outlet = self.calculate_borefield_inlet_outlet_temperature(
-                        self.load.hourly_net_resulting_injection_power, results.peak_injection,
-                        simulation_period=self.load.simulation_period)
+                        hourly_load, results.peak_injection, simulation_period=self.load.simulation_period)
                     if sizing:
                         results._Tf_extraction_inlet, results._Tf_extraction_outlet = self.calculate_borefield_inlet_outlet_temperature(
-                            self.load.hourly_net_resulting_injection_power, results._Tf_extraction,
-                            simulation_period=self.load.simulation_period)
+                            hourly_load, results._Tf_extraction, simulation_period=self.load.simulation_period)
             return results
 
         def calculate_difference(results_old: Union[ResultsMonthly, ResultsHourly],
                                  result_new: Union[ResultsMonthly, ResultsHourly]) -> float:
             return max(
-                np.max(result_new.peak_injection - results_old.peak_injection),
-                np.max(result_new.peak_extraction - results_old.peak_extraction))
+                np.max(np.abs(result_new.peak_injection - results_old.peak_injection)),
+                np.max(np.abs(result_new.peak_extraction - results_old.peak_extraction)))
 
         if isinstance(self.load, _LoadDataBuilding) or \
                 isinstance(self.borehole.fluid_data, TemperatureDependentFluidData):

GHEtool/Examples/sizing_with_building_load_hourly.py

@@ -57,6 +57,7 @@ def L3_sizing() -> Tuple[float, float]:
     print(
         f'When sizing with an L3 method, the required borehole length is {length:.2f}m. '
         f'The SCOP is {borefield.load.SCOP_total:.2f}.')
+    borefield.load.SEER
     borefield.print_temperature_profile()
     return length, borefield.load.SCOP_heating
 

GHEtool/Examples/sizing_with_building_load_hourly_limit.py

@@ -0,0 +1,174 @@
+"""
+This document contains an example on sizing with an hourly building load and the difference between L3 and L4 sizing.
+It can be seen that sizing with an hourly method not only gives a completely different result, but also that the SCOP
+differs and is more accurate.
+"""
+
+from GHEtool import *
+from GHEtool.VariableClasses.Efficiency._Efficiency import combine_n_heat_pumps
+from typing import Tuple
+
+# initiate ground data
+data = GroundFluxTemperature(2.1, 10, flux=0.07)
+borefield_gt = gt.borefield.Borefield.rectangle_field(10, 12, 6, 6, 110, 1, 0.075)
+
+points_HP500 = np.array([
+    [-4.5, 84.7],
+    [-4.5, 66.3],
+    [-4.5, 38.6],
+    [-1.5, 93.0],
+    [-1.5, 72.9],
+    [-1.5, 42.4],
+    [3.5, 107.8],
+    [3.5, 84.6],
+    [3.5, 49.4],
+    [8.5, 123.5],
+    [8.5, 97.4],
+    [8.5, 56.9],
+    [11.5, 133.2],
+    [11.5, 105.4],
+    [11.5, 61.4],
+])
+eff_HP500 = np.array([
+    3.87, 4.12, 3.78,
+    4.12, 4.39, 4.04,
+    4.57, 4.89, 4.49,
+    5.10, 5.50, 5.08,
+    5.48, 5.92, 5.48,
+])
+points_HP400 = np.array([
+    [-4.5, 67.2],
+    [-4.5, 49.9],
+    [-4.5, 29.1],
+    [-1.5, 73.7],
+    [-1.5, 54.8],
+    [-1.5, 32.0],
+    [3.5, 85.2],
+    [3.5, 63.5],
+    [3.5, 37.2],
+    [8.5, 97.7],
+    [8.5, 73.1],
+    [8.5, 42.7],
+    [11.5, 105.7],
+    [11.5, 79.0],
+    [11.5, 46.0],
+])
+eff_HP400 = np.array([
+    3.91, 4.38, 3.99,
+    4.14, 4.64, 4.27,
+    4.58, 5.16, 4.77,
+    5.12, 5.80, 5.34,
+    5.51, 6.22, 5.75,
+])
+cascaded_system_points, cascaded_system_eff = combine_n_heat_pumps([points_HP500] * 4 + [points_HP400],
+                                                                   [eff_HP500] * 4 + [eff_HP400])
+
+cop_system = COP(cascaded_system_eff, cascaded_system_points, True)
+
+
+def L3_sizing() -> Tuple[float, float]:
+    """
+    Size the borefield with a monthly sizing method.
+
+    Returns
+    -------
+    length, SCOP
+    """
+    # initiate borefield
+    borefield = Borefield()
+
+    # set parameters
+    borefield.set_min_fluid_temperature(0)
+    borefield.set_max_fluid_temperature(25)
+
+    # set ground data in borefield
+    borefield.ground_data = data
+
+    # set Rb
+    borefield.Rb = 0.12
+
+    # set borefield
+    borefield.set_borefield(borefield_gt)
+
+    # load the hourly profile
+    load = HourlyBuildingLoad(efficiency_heating=cop_system)
+    load.load_hourly_profile(FOLDER.joinpath("Examples/hourly_profile.csv"), header=True, separator=";")
+    borefield.load = load
+
+    # size the borefield and plot the resulting temperature evolution
+    length = borefield.size(100, L3_sizing=True)
+    print(
+        f'When sizing with an L3 method (without limit), the required borehole length is {length:.2f}m. '
+        f'The SCOP is {borefield.load.SCOP_total:.2f}.')
+
+    # with limit
+    borefield.load._limit_to_max_heat_pump_power = True
+    length = borefield.size(100, L3_sizing=True)
+    borefield.print_temperature_profile()
+    return length
+
+
+def L4_sizing() -> Tuple[float, float]:
+    """
+    Size the borefield with an hourly sizing method.
+
+    Returns
+    -------
+    length, SCOP
+    """
+    # initiate borefield
+    borefield = Borefield()
+
+    # set parameters
+    borefield.set_min_fluid_temperature(0)
+    borefield.set_max_fluid_temperature(25)
+
+    # set ground data in borefield
+    borefield.ground_data = data
+
+    # set Rb
+    borefield.Rb = 0.12
+
+    # set borefield
+    borefield.set_borefield(borefield_gt)
+
+    # load the hourly profile
+    load = HourlyBuildingLoad(efficiency_heating=cop_system)
+    load.load_hourly_profile(FOLDER.joinpath("Examples/hourly_profile.csv"), header=True, separator=";")
+    borefield.load = load
+
+    # size the borefield and plot the resulting temperature evolution
+    length = borefield.size(100, L4_sizing=True)
+    print(
+        f'When sizing with an L4 method, the required borehole length is {length:.2f}m. '
+        f'The SCOP is {borefield.load.SCOP_total:.2f}.')
+    borefield.load._limit_to_max_heat_pump_power = True
+    length = borefield.size(100, L4_sizing=True)
+    print(
+        f'When sizing with an L4 method (with limit), the required borehole length is {length:.2f}m. '
+        f'The SCOP is {borefield.load.SCOP_total:.2f}.')
+    missing_power = borefield.load.hourly_heating_load_simulation_period - borefield.load.cop._get_max_power(
+        borefield.results.Tf)
+    missing_power = np.maximum(missing_power, 0)
+    print(f'Over the whole simulation period, a maximum of {max(missing_power):.2f} kW cannot be delivered by the '
+          f'cascaded heat pumps at 0°C. This accumulates to {np.sum(missing_power):.2f} kWh over the whole simulation period.')
+
+    borefield.set_min_fluid_temperature(3)
+    length = borefield.size(100, L4_sizing=True)
+    print(
+        f'When sizing with an L4 method (with limit at 3°C), the required borehole length is {length:.2f}m. '
+        f'The SCOP is {borefield.load.SCOP_total:.2f}.')
+    missing_power = borefield.load.hourly_heating_load_simulation_period - borefield.load.cop._get_max_power(
+        borefield.results.Tf)
+    missing_power = np.maximum(missing_power, 0)
+    print(f'Over the whole simulation period, a maximum of {max(missing_power):.2f} kW cannot be delivered by the '
+          f'cascaded heat pumps at 0°C. This accumulates to {np.sum(missing_power):.2f} kWh over the whole simulation period.')
+
+    borefield.print_temperature_profile(plot_hourly=True)
+    borefield.load.SEER
+    return length, borefield.load.SCOP_heating
+
+
+if __name__ == "__main__":
+    L3_sizing()
+    L4_sizing()

GHEtool/Examples/variable_flow_rate.py

@@ -79,12 +79,30 @@ def sizing():
     plt.legend()
     plt.ylabel('Average fluid temperature [°C]')
     plt.xlabel('Time [years]')
+    plt.title('Borehole fluid temperature')
 
     plt.figure()
     plt.plot(time_array, rb_variable_flow, label='variable flow')
     plt.plot(time_array, rb_constant_flow, label='constant flow')
     plt.ylabel('Effective borehole thermal resistance [mK/W]')
     plt.xlabel('Time [years]')
+    plt.title('Effective borehole thermal resistance')
+    plt.legend()
+
+    plt.figure()
+    plt.plot(time_array[:8760], borefield_variable_flow.results.peak_injection[:8760], label='variable flow')
+    plt.plot(time_array[:8760], borefield_constant_flow.results.peak_injection[:8760], label='constant flow')
+    plt.legend()
+    plt.title('Borehole fluid temperature')
+    plt.ylabel('Average fluid temperature [°C]')
+    plt.xlabel('Time [years]')
+
+    plt.figure()
+    plt.plot(time_array[:8760], rb_variable_flow[:8760], label='variable flow')
+    plt.plot(time_array[:8760], rb_constant_flow[:8760], label='constant flow')
+    plt.ylabel('Effective borehole thermal resistance [mK/W]')
+    plt.title('Effective borehole thermal resistance')
+    plt.xlabel('Time [years]')
     plt.legend()
     plt.show()