comparison of vertical vs horizontal panels

Utilities/Shading.py

@@ -2,7 +2,6 @@ import numpy as np
 import pandas as pd
 import logging
 import math
-from tqdm import tqdm
 
 import pvlib
 
@@ -23,7 +22,7 @@ def get_location(c):
     return location
 
 
-def define_grid_layout(c):
+def define_grid_layout(c, panel_tilt):
     # get number of panels required
     no_of_panels = calculate_no_of_panels(
         c["array"]["system_size"], c["panel"]["peak_power"]
@@ -33,7 +32,7 @@ def define_grid_layout(c):
     pitch = c["array"]["spacing"] + c["panel"]["dimensions"]["thickness"]
     # calculate minimum pitch if we don't want panel overlap at all
     min_pitch = c["panel"]["dimensions"]["length"] * math.cos(
-        c["array"]["tilt"] / 180 * math.pi
+        panel_tilt / 180 * math.pi
     )
     if pitch < min_pitch:
         logger.warning(
@@ -129,8 +128,8 @@ def get_solar_data(c):
     return solar_positions, clearsky_data
 
 
-def calculate_shading(c):
+def calculate_energy_production_vertical(c):
-    panel_coordinates, no_of_panels = define_grid_layout(c)
+    panel_coordinates, no_of_panels = define_grid_layout(c, panel_tilt=90)
     solar_positions, clearsky_data = get_solar_data(c)
 
     # split the solar positions data into morning and afternoon, using solar azimuth of
@@ -146,10 +145,10 @@ def calculate_shading(c):
     # calculate delta between unique y coordinates of panels to get pitch
     pitch = np.unique(panel_coordinates["y"])[1] - np.unique(panel_coordinates["y"])[0]
     surface_to_axis_offset = 0
-    shaded_row_rotation = c["array"]["tilt"]
+    shaded_row_rotation = 90
-    shading_row_rotation = c["array"]["tilt"]
+    shading_row_rotation = 90
     axis_tilt = 0
-    axis_azimuth = c["array"]["front_face_azimuth"]
+    axis_azimuth = 90
 
     morning_shaded_fraction = pvlib.shading.shaded_fraction1d(
         solar_zenith=morning_solar_positions["zenith"],
@@ -184,25 +183,27 @@ def calculate_shading(c):
 
     # calculate irradiance on plane of array
     poa_front = pvlib.irradiance.get_total_irradiance(
-        surface_tilt=c["array"]["tilt"],
+        surface_tilt=90,
-        surface_azimuth=c["array"]["front_face_azimuth"],
+        surface_azimuth=axis_azimuth,
         solar_zenith=morning_solar_positions["zenith"],
         solar_azimuth=morning_solar_positions["azimuth"],
         dni=clearsky_data["dni"],
         ghi=clearsky_data["ghi"],
         dhi=clearsky_data["dhi"],
+        albedo=0.5,
     )
     # drop rows with poa_global NaN values
     poa_front = poa_front.dropna(subset=["poa_global"])
 
     poa_rear = pvlib.irradiance.get_total_irradiance(
-        surface_tilt=180 - c["array"]["tilt"],
+        surface_tilt=180 - 90,
-        surface_azimuth=c["array"]["front_face_azimuth"] + 180,
+        surface_azimuth=axis_azimuth + 180,
         solar_zenith=afternoon_solar_positions["zenith"],
         solar_azimuth=afternoon_solar_positions["azimuth"],
         dni=clearsky_data["dni"],
         ghi=clearsky_data["ghi"],
         dhi=clearsky_data["dhi"],
+        albedo=0.5,
     )
     # drop rows with poa_global NaN values
     poa_rear = poa_rear.dropna(subset=["poa_global"])
@@ -221,10 +222,74 @@ def calculate_shading(c):
 
     energy_front = effective_front * 15 / 60 / 1e3
     energy_rear = effective_rear * 15 / 60 / 1e3
-    energy_total = energy_front.sum() + energy_rear.sum()
+    total_hourly_energy_m2 = energy_front.add(energy_rear, fill_value=0)
+    energy_total = total_hourly_energy_m2.sum()
     logger.info(f"Energy yield calculated: {energy_total} kWh/m2")
 
     panel_area = c["panel"]["dimensions"]["length"] * c["panel"]["dimensions"]["width"]
     total_area = panel_area * no_of_panels
-    total_energy = energy_total * total_area
+    total_hourly_energy = total_hourly_energy_m2 * total_area
+    total_energy = total_hourly_energy.sum()
     logger.info(f"Total energy yield calculated: {total_energy} kWh")
+
+    return total_hourly_energy
+
+
+def calculate_energy_production_horizontal(c):
+    panel_coordinates, no_of_panels = define_grid_layout(c, panel_tilt=0)
+    solar_positions, clearsky_data = get_solar_data(c)
+
+    # the first row is always not shaded so exclude
+    no_of_rows = np.unique(panel_coordinates["y"]).shape[0]
+    no_of_shaded_rows = no_of_rows - 1
+
+    collector_width = c["panel"]["dimensions"]["length"]
+    # calculate delta between unique y coordinates of panels to get pitch
+    pitch = np.unique(panel_coordinates["y"])[1] - np.unique(panel_coordinates["y"])[0]
+    surface_to_axis_offset = 0
+    shaded_row_rotation = 0
+    shading_row_rotation = 0
+    axis_tilt = 0
+    axis_azimuth = 180  # south facing
+
+    shaded_fraction = pvlib.shading.shaded_fraction1d(
+        solar_zenith=solar_positions["zenith"],
+        solar_azimuth=solar_positions["azimuth"],
+        axis_azimuth=axis_azimuth,
+        shaded_row_rotation=shaded_row_rotation,
+        shading_row_rotation=shading_row_rotation,
+        collector_width=collector_width,
+        pitch=pitch,
+        surface_to_axis_offset=surface_to_axis_offset,
+        axis_tilt=axis_tilt,
+    )
+    shaded_fraction = shaded_fraction * no_of_shaded_rows / no_of_rows
+    logger.info(f"Shaded fraction calculated for solar positions.")
+
+    poa = pvlib.irradiance.get_total_irradiance(
+        surface_tilt=0,
+        surface_azimuth=axis_azimuth,
+        solar_zenith=solar_positions["zenith"],
+        solar_azimuth=solar_positions["azimuth"],
+        dni=clearsky_data["dni"],
+        ghi=clearsky_data["ghi"],
+        dhi=clearsky_data["dhi"],
+        surface_type="urban",
+    )
+    poa = poa.dropna(subset=["poa_global"])
+
+    effective_front = (
+        poa["poa_global"] * (1 - shaded_fraction) * c["panel"]["efficiency"]
+    )
+
+    total_hourly_energy_m2 = effective_front * 15 / 60 / 1e3
+    energy_total = total_hourly_energy_m2.sum()
+    logger.info(f"Energy yield calculated: {energy_total} kWh/m2")
+
+    panel_area = c["panel"]["dimensions"]["length"] * c["panel"]["dimensions"]["width"]
+    total_area = panel_area * no_of_panels
+    total_hourly_energy = total_hourly_energy_m2 * total_area
+    total_energy = total_hourly_energy.sum()
+    logger.info(f"Total energy yield calculated: {total_energy} kWh")
+
+    return total_hourly_energy

config.yml

@@ -1,9 +1,8 @@
 array:
   system_size: 400 # in kWp
-  spacing: 0.5 # spacing between adjacent panel rows in m
+  spacing: 1 # spacing between adjacent panel rows in m
   edge_setback: 1.8 # distance from the edge of the roof to the array
-  front_face_azimuth: 90 # 90=east, 180=south, 270=west
+  roof_slope: 0
-  tilt: 90 # just 0 and 90 are supported for now
   slope: 0 # degrees from horizontal (+ve means shaded row is higher than the row in front)
 
 simulation_date_time:

main.py

@@ -1,7 +1,12 @@
 # %%
 import yaml
 import logging
-from Utilities.Shading import calculate_shading
+import numpy as np
+import matplotlib.pyplot as pl
+from Utilities.Shading import (
+    calculate_energy_production_horizontal,
+    calculate_energy_production_vertical,
+)
 
 logging.basicConfig(
     level=logging.INFO,
@@ -24,7 +29,37 @@ with open(config_path, "r") as file:
 logger.info("Configuration loaded successfully.")
 logger.debug(f"Configuration: {c}")
 
-shading = calculate_shading(c)
+# calculate energy production for horizontal and vertical panels
-logger.info("Shading calculation completed successfully.")
+horizontal_energy = calculate_energy_production_horizontal(c)
+logger.info("Energy production for horizontal panels calculated successfully.")
+logger.debug(f"Horizontal Energy Production: {horizontal_energy.sum()}")
 
-# %%
+vertical_energy = calculate_energy_production_vertical(c)
+logger.info("Energy production for vertical panels calculated successfully.")
+logger.debug(f"Vertical Energy Production: {vertical_energy.sum()}")
+
+NOVA_scaledown = 0.75
+
+horizontal_energy_scaled = horizontal_energy * NOVA_scaledown
+logger.info("Energy production for horizontal panels scaled down to NOVA requirement.")
+
+logger.info(
+    f"Energy production for horizontal panels: {np.round(horizontal_energy_scaled.sum(),0)} kWh"
+)
+logger.info(
+    f"Energy production for vertical panels: {np.round(vertical_energy.sum(),0)} kWh"
+)
+
+# overlay horizontal and vertical energy production
+pl.figure(figsize=(10, 6))
+pl.plot(
+    horizontal_energy_scaled.index,
+    horizontal_energy_scaled.values,
+    label="Horizontal Panels",
+)
+pl.plot(vertical_energy.index, vertical_energy.values, label="Vertical Panels")
+pl.title("Energy Production Comparison")
+pl.xlabel("Time")
+pl.ylabel("Energy Production (kWh)")
+pl.legend()
+pl.show()