Add pinch point temperature

inputs/plants.yaml

@@ -11,6 +11,7 @@
 desalination_plants:
   - name: default_med
     operating_hours: !!int 10  # Number of operating hours per day
+    pinch_point_temperature_difference: !!float 1
     plant_disabled:
       requirements:
         electricity: !!float 30  # [kW] Electricity requirements
@@ -39,6 +40,7 @@ desalination_plants:
   # NOTE: This plant is capable of producing 3 m^3 of desalinated water per day.
   - name: !!str joo_med_24_hour
     operating_hours: !!int 24  # Number of operating hours per day
+    pinch_point_temperature_difference: !!float 1
     plant_disabled:
       requirements:
         electricity: !!float 0  # [kW] Electricity requirements
@@ -67,6 +69,7 @@ desalination_plants:
   # day and runs for 24 hours of the day.
   - name: !!str el_nashar_24_hour
     operating_hours: !!int 24  # Number of operating hours per day
+    pinch_point_temperature_difference: !!float 1
     plant_disabled:
       requirements:
         electricity: !!float 0  # [kW] Electricity requirements
@@ -96,6 +99,7 @@ desalination_plants:
   # day and runs for 24 hours of the day.
   - name: !!str rahimi_24_hour
     operating_hours: !!int 24  # Number of operating hours per day
+    pinch_point_temperature_difference: !!float 1
     plant_disabled:
       requirements:
         electricity: !!float 0  # [kW] Electricity requirements

plotter.py

@@ -313,7 +313,7 @@
 
 ALPHA = 0.9
 sns.set_style("whitegrid")
-sns.set_context("notebook")
+sns.set_context("poster")
 
 colorblind_palette = sns.color_palette(
     [
@@ -2949,7 +2949,7 @@
 sns.set_palette(colorblind_palette)
 
 # Read input data
-with open("31_mar_23_v2.json", "r", encoding="UTF-8") as f:
+with open("clean_water_optimisations_data.json", "r", encoding="UTF-8") as f:
     full_data = json.load(f)
 
 data = {
@@ -7928,7 +7928,7 @@ def _post_process_split_axes(ax1, ax2):
 
 # Plot using an added 10% height ONLY to the error bars
 
-fig, axes = plt.subplots(2, 2, figsize=(48 / 5, 32 / 5))
+fig, axes = plt.subplots(2, 2, figsize=(15, 10))
 fig.subplots_adjust(hspace=0.35)
 
 
@@ -8079,7 +8079,7 @@ def _post_process_split_axes(ax1, ax2):
 data_to_plot = data_to_plot.drop("Total").transpose()
 data_to_plot.plot.bar(ax=(axis := axes[0, 1]), rot=0, stacked=True, edgecolor="none")
 axis.errorbar(
-    x=data_to_error_bar.index,
+    x=data_to_plot.index,
     y=[(y_min[index] + max_entry) / 2 for index, max_entry in enumerate(y_max)],
     yerr=[abs(max_entry - y_min[index]) / 2 for index, max_entry in enumerate(y_max)],
     capsize=10,
@@ -8305,9 +8305,9 @@ def _post_process_split_axes(ax1, ax2):
 
 
 plt.savefig(
-    "specific_costs_comparison_15_10_percent_error.png",
+    "specific_costs_comparison_poster_15_10_percent_error.png",
     transparent=True,
-    dpi=300,
+    dpi=1200,
     bbox_inches="tight",
 )
 
@@ -9012,7 +9012,7 @@ def _post_process_split_axes(ax1, ax2):
 
 import math
 
-fig, axes = plt.subplots(2, 2, figsize=(48 / 5, 32 / 5))
+fig, axes = plt.subplots(2, 2, figsize=(15, 10))
 fig.subplots_adjust(hspace=0.35)
 
 K_DEPTH: int = 3
@@ -9245,14 +9245,14 @@ def _post_process_split_axes(ax1, ax2):
 data_to_plot.plot.bar(ax=axis, rot=0, stacked=True, edgecolor="none")
 axis.grid(axis="x")
 axis.set_xlabel("MED Plant")
-axis.set_ylabel("Specific emissions / kg CO$_2$eq/m$^3$")
+axis.set_ylabel("Spec. emissions / kg CO$_2$eq/m$^3$")
 axis.set_title("Abu Dhabi, UAE")
 axis.yaxis.set_minor_formatter(ticker.ScalarFormatter())
 axis.yaxis.set_major_formatter(ticker.ScalarFormatter())
 axis.set_ylim(0, specific_emissions_y_lim)
 axis.text(
-    -0.08,
-    1.1,
+    0,
+    1.15,
     "a.",
     transform=axis.transAxes,
     fontsize=16,
@@ -9385,12 +9385,12 @@ def _post_process_split_axes(ax1, ax2):
 data_to_plot.plot.bar(ax=axis, rot=0, stacked=True, edgecolor="none")
 axis.grid(axis="x")
 axis.set_xlabel("MED Plant")
-axis.set_ylabel("Specific emissions / kg CO$_2$eq/m$^3$")
+axis.set_ylabel("Spec. emissions / kg CO$_2$eq/m$^3$")
 axis.set_title("Gando, Gran Canaria")
 axis.set_ylim(0, specific_emissions_y_lim)
 axis.text(
-    -0.08,
-    1.1,
+    0,
+    1.15,
     "b.",
     transform=axis.transAxes,
     fontsize=16,
@@ -9519,12 +9519,12 @@ def _post_process_split_axes(ax1, ax2):
 data_to_plot.plot.bar(ax=axis, rot=0, stacked=True, edgecolor="none")
 axis.grid(axis="x")
 axis.set_xlabel("MED Plant")
-axis.set_ylabel("Specific emissions / kg CO$_2$eq/m$^3$")
+axis.set_ylabel("Spec. emissions / kg CO$_2$eq/m$^3$")
 axis.set_ylim(0, specific_emissions_y_lim)
 axis.set_title("Tijuana, Mexico")
 axis.text(
-    -0.08,
-    1.1,
+    0,
+    1.15,
     "c.",
     transform=axis.transAxes,
     fontsize=16,
@@ -9653,12 +9653,12 @@ def _post_process_split_axes(ax1, ax2):
 data_to_plot.plot.bar(ax=axis, rot=0, stacked=True, edgecolor="none")
 axis.grid(axis="x")
 axis.set_xlabel("MED Plant")
-axis.set_ylabel("Specific emissions / kg CO$_2$eq/m$^3$")
+axis.set_ylabel("Spec. emissions / kg CO$_2$eq/m$^3$")
 axis.set_ylim(0, specific_emissions_y_lim)
 axis.set_title("La Paz, Mexico")
 axis.text(
-    -0.08,
-    1.1,
+    0,
+    1.15,
     "d.",
     transform=axis.transAxes,
     fontsize=16,
@@ -9691,7 +9691,7 @@ def _post_process_split_axes(ax1, ax2):
 plt.savefig(
     "specific_emissions_comparison_15.png",
     transparent=True,
-    dpi=300,
+    dpi=1200,
     bbox_inches="tight",
 )
 
@@ -11278,7 +11278,7 @@ def plot_battery_inverter_line_map(
 )
 
 axis.set_xlabel("Specific cost / USD/m$^3$")
-axis.set_ylabel("Specific emissions / kg CO$_2$eq/m$^3$")
+axis.set_ylabel("Spec. emissions / kg CO$_2$eq/m$^3$")
 axis.set_title("Smallest-capacity plant")
 locmin = mticker.LogLocator(base=10, subs=np.arange(0.1, 10, 0.1), numticks=100)
 
@@ -11525,7 +11525,7 @@ def _post_process_split_kde_axes(ax1, ax2):
     bw_adjust=bw_adjust,
 )
 axis.set_xlabel("Specific cost / USD/m$^3$")
-axes[0].set_ylabel("Specific emissions / kg CO$_2$eq/m$^3$")
+axes[0].set_ylabel("Spec. emissions / kg CO$_2$eq/m$^3$")
 axis.set_title("Medium-capacity plant")
 axis.set_ylabel("")
 
@@ -11711,7 +11711,7 @@ def _post_process_split_kde_axes(ax1, ax2):
 )
 
 axis.set_xlabel("Specific cost / USD/m$^3$")
-axis.set_ylabel("Specific emissions / kg CO$_2$eq/m$^3$")
+axis.set_ylabel("Spec. emissions / kg CO$_2$eq/m$^3$")
 axis.set_title("Medium-capacity plant")
 
 axis.legend()
@@ -11956,7 +11956,7 @@ def _post_process_split_kde_axes(ax1, ax2):
     bw_adjust=bw_adjust,
 )
 axis.set_xlabel("Specific cost / USD/m$^3$")
-axes[0].set_ylabel("Specific emissions / kg CO$_2$eq/m$^3$")
+axes[0].set_ylabel("Spec. emissions / kg CO$_2$eq/m$^3$")
 # axis.set_title("Medium-capacity plant")
 axis.set_ylabel("")
 
@@ -12143,7 +12143,7 @@ def _post_process_split_kde_axes(ax1, ax2):
 )
 
 axis.set_xlabel("Specific cost / USD/m$^3$")
-axis.set_ylabel("Specific emissions / kg CO$_2$eq/m$^3$")
+axis.set_ylabel("Spec. emissions / kg CO$_2$eq/m$^3$")
 axis.set_title("Medium-capacity plant")
 
 axis.legend()
@@ -12396,7 +12396,7 @@ def _post_process_split_kde_axes(ax1, ax2):
     ha="center",
     va="center",
 )
-axes[0].set_ylabel("Specific emissions / kg CO$_2$eq/m$^3$")
+axes[0].set_ylabel("Spec. emissions / kg CO$_2$eq/m$^3$")
 plt.figtext(
     0.5,
     axis.get_position().y1 + 0.014,

src/heatdesalination/heat_pump.py

@@ -110,6 +110,7 @@ def get_emissions(self, thermal_power: float) -> float:
 def _coefficient_of_performance(
     condensation_temperature: float,
     evaporation_temperature: float,
+    pinch_point_temperature_difference: float,
     system_efficiency: float,
 ) -> float:
     """
@@ -135,6 +136,10 @@ def _coefficient_of_performance(
             the temperature at which heat is absorbed from the environment in order to
             evaporate the heat-transfer fluid (refrigerant) within the heat pump,
             measured in degrees Kelvin.
+        - pinch_point_temperature_difference:
+            The temperature difference between the desired condensation and evaporation
+            temperatures and the real temperatures achieved, dictated by the effective
+            possible rate of heat transfer across the heat exchangers in the system.
         - system_efficiency:
             The efficiency of the heat pump system given as a fraction of its efficiency
             against the Carnot efficiency.
@@ -146,7 +151,7 @@ def _coefficient_of_performance(
 
     return (
         system_efficiency
-        * condensation_temperature
+        * (condensation_temperature + pinch_point_temperature_difference)
         / (condensation_temperature - evaporation_temperature)
     )
 
@@ -156,6 +161,7 @@ def calculate_heat_pump_electricity_consumption_and_cost_and_emissions(
     evaporation_temperature: float,
     heat_demand: float,
     heat_pump: HeatPump,
+    pinch_point_temperature_difference,
 ) -> Tuple[float, float, float]:
     """
     Calculate the electricity comsumption and the cost and emissions of the heat pump.
@@ -189,6 +195,10 @@ def calculate_heat_pump_electricity_consumption_and_cost_and_emissions(
             The heat demand flux, measured in kiloWatts.
         - heat_pump:
             The heat pump currently being considered.
+        - pinch_point_temperature_difference:
+            The temperature difference between the desired condensation and evaporation
+            temperatures and the real temperatures achieved, dictated by the effective
+            possible rate of heat transfer across the heat exchangers in the system.
 
     Outputs:
         - The cost of the heat pump in USD,
@@ -199,7 +209,10 @@ def calculate_heat_pump_electricity_consumption_and_cost_and_emissions(
 
     power_consumption = heat_demand / (
         cop := _coefficient_of_performance(
-            condensation_temperature, evaporation_temperature, heat_pump.efficiency
+            condensation_temperature,
+            evaporation_temperature,
+            pinch_point_temperature_difference,
+            heat_pump.efficiency,
         )
     )
     cost = heat_pump.get_cost(cop, heat_demand)

src/heatdesalination/plant.py

@@ -49,6 +49,10 @@
 #   Keyword for plant outputs.
 OUTPUTS: str = "outputs"
 
+# PINCH_POINT_TEMPERATURE_DIFFERENCE:
+#   Keyword for the pinch-point temperature difference.
+PINCH_POINT_TEMPERATURE_DIFFERENCE: str = "pinch_point_temperature_difference"
+
 # PLANT_DISABLED:
 #   Keyword for when the plant is disabled, i.e., not operating.
 PLANT_DISABLED: str = "plant_disabled"
@@ -149,6 +153,11 @@ class DesalinationPlant:
     .. attribute:: operating_hours
         The number of hours a day that the plant is operating.
 
+    .. attribute:: pinch_point_temperature_difference
+        The temperature difference between the desired condensation and evaporation
+        temperatures and the real temperatures achieved, dictated by the effective
+        possible rate of heat transfer across the heat exchangers in the system.
+
     .. attribute:: plant_outputs
         The outputs of the plant when in operation (True) and not in operation (False).
 
@@ -165,6 +174,7 @@ def __init__(
         self,
         name: str,
         operating_hours: int,
+        pinch_point_temperature_difference: float,
         plant_outputs: dict[bool, PlantOutputs],
         plant_requirements: dict[bool, PlantRequirements],
         start_hour: int,
@@ -177,6 +187,11 @@ def __init__(
                 The name of the desalination plant.
             - operating_hours:
                 The number of hours a day that the plant is in operation.
+            - pinch_point_temperature_difference:
+                The temperature difference between the desired condensation and
+                evaporation temperatures and the real temperatures achieved, dictated by
+                the effective possible rate of heat transfer across the heat exchangers
+                in the system.
             - plant_outputs:
                 The outputs from the desalination plant.
             - plant_reqiurements:
@@ -191,6 +206,9 @@ def __init__(
         )
         self.name: str = name
         self.operating_hours = operating_hours
+        self.pinch_point_temperature_difference: float = (
+            pinch_point_temperature_difference
+        )
         self.plant_outputs: dict[bool, PlantOutputs] = plant_outputs
         self.plant_requirements: dict[bool, PlantRequirements] = plant_requirements
         self.start_hour: int = start_hour
@@ -264,6 +282,7 @@ def from_dict(
         return cls(
             input_data[NAME],
             input_data[OPERATING_HOURS],
+            input_data.get(PINCH_POINT_TEMPERATURE_DIFFERENCE, 0),
             plant_outputs,
             plant_requirements,
             start_hour,

src/heatdesalination/simulator.py

@@ -854,6 +854,7 @@ def run_simulation(  # pylint: disable=too-many-statements
                 ambient_temperatures[hour],
                 auxiliary_heating_demand,
                 heat_pump,
+                desalination_plant.pinch_point_temperature_difference,
             )
 
             auxiliary_heating_electricity_demand: float = max(