From 379d1f88686a8d51cea221b5553d857a1458dcf1 Mon Sep 17 00:00:00 2001
From: cbcrespo <cbcrespo@fc.ul.pt>
Date: Tue, 9 Jun 2026 10:33:23 +0100
Subject: [PATCH 1/3] Remove empty horizon brightening component from haydavies

---
 pvlib/irradiance.py      | 5 +----
 tests/test_irradiance.py | 6 ++----
 2 files changed, 3 insertions(+), 8 deletions(-)

diff --git a/pvlib/irradiance.py b/pvlib/irradiance.py
index 50f02426de..df9ed37b9e 100644
--- a/pvlib/irradiance.py
+++ b/pvlib/irradiance.py
@@ -797,8 +797,7 @@ def haydavies(surface_tilt, surface_azimuth, dhi, dni, dni_extra,
             * poa_sky_diffuse: Total sky diffuse
             * poa_isotropic
             * poa_circumsolar
-            * poa_horizon (always zero, not accounted for by the
-              Hay-Davies model)
+        The model does not support a horizon brightening component.
 
     Notes
     ------
@@ -862,8 +861,6 @@ def haydavies(surface_tilt, surface_azimuth, dhi, dni, dni_extra,
         # Calculate the individual components
         diffuse_components['poa_isotropic'] = poa_isotropic
         diffuse_components['poa_circumsolar'] = poa_circumsolar
-        diffuse_components['poa_horizon'] = np.where(
-            np.isnan(diffuse_components['poa_isotropic']), np.nan, 0.)
 
         if isinstance(sky_diffuse, pd.Series):
             diffuse_components = pd.DataFrame(diffuse_components)
diff --git a/tests/test_irradiance.py b/tests/test_irradiance.py
index a416636ae9..839ea45316 100644
--- a/tests/test_irradiance.py
+++ b/tests/test_irradiance.py
@@ -209,13 +209,11 @@ def test_haydavies(irrad_data, ephem_data, dni_et):
 
 
 def test_haydavies_components(irrad_data, ephem_data, dni_et):
-    keys = ['poa_sky_diffuse', 'poa_isotropic', 'poa_circumsolar',
-            'poa_horizon']
+    keys = ['poa_sky_diffuse', 'poa_isotropic', 'poa_circumsolar']
     expected = pd.DataFrame(np.array(
         [[0, 27.1775, 102.9949, 33.1909],
          [0, 27.1775, 30.1818, 27.9837],
-         [0, 0, 72.8130, 5.2071],
-         [0, 0, 0, 0]]).T,
+         [0, 0, 72.8130, 5.2071]]).T,
         columns=keys,
         index=irrad_data.index
     )

From 25b9f274ba8579dec54572ffae04e04b9611f483 Mon Sep 17 00:00:00 2001
From: cbcrespo <cbcrespo@fc.ul.pt>
Date: Mon, 15 Jun 2026 11:18:48 +0100
Subject: [PATCH 2/3] Change OrderedDict to Dict

---
 pvlib/irradiance.py | 15 +++++++--------
 1 file changed, 7 insertions(+), 8 deletions(-)

diff --git a/pvlib/irradiance.py b/pvlib/irradiance.py
index df9ed37b9e..8651af8fe2 100644
--- a/pvlib/irradiance.py
+++ b/pvlib/irradiance.py
@@ -783,7 +783,7 @@ def haydavies(surface_tilt, surface_azimuth, dhi, dni, dni_extra,
 
     Returns
     --------
-    numeric, OrderedDict, or DataFrame
+    numeric, Dict, or DataFrame
         Return type controlled by ``return_components`` argument.
         If `False`, ``sky_diffuse`` is returned.
         If `True`, ``diffuse_components`` is returned.
@@ -792,7 +792,7 @@ def haydavies(surface_tilt, surface_azimuth, dhi, dni, dni_extra,
         The sky diffuse component of the solar radiation on a tilted
         surface. [Wm⁻²]
 
-    diffuse_components : OrderedDict (array input) or DataFrame (Series input)
+    diffuse_components : Dict (array input) or DataFrame (Series input)
         Keys/columns are:
             * poa_sky_diffuse: Total sky diffuse
             * poa_isotropic
@@ -855,12 +855,11 @@ def haydavies(surface_tilt, surface_azimuth, dhi, dni, dni_extra,
     sky_diffuse = poa_isotropic + poa_circumsolar
 
     if return_components:
-        diffuse_components = OrderedDict()
-        diffuse_components['poa_sky_diffuse'] = sky_diffuse
-
-        # Calculate the individual components
-        diffuse_components['poa_isotropic'] = poa_isotropic
-        diffuse_components['poa_circumsolar'] = poa_circumsolar
+        diffuse_components = {
+            'poa_sky_diffuse': sky_diffuse,
+            'poa_isotropic': poa_isotropic,
+            'poa_circumsolar': poa_circumsolar
+        }
 
         if isinstance(sky_diffuse, pd.Series):
             diffuse_components = pd.DataFrame(diffuse_components)

From 6ebc8988f46da99e87685df995854b8b83e200a0 Mon Sep 17 00:00:00 2001
From: "Adam R. Jensen" <39184289+AdamRJensen@users.noreply.github.com>
Date: Fri, 19 Jun 2026 11:02:46 +0200
Subject: [PATCH 3/3] Apply suggestion from @AdamRJensen

---
 pvlib/irradiance.py | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/pvlib/irradiance.py b/pvlib/irradiance.py
index 8651af8fe2..c491fdd884 100644
--- a/pvlib/irradiance.py
+++ b/pvlib/irradiance.py
@@ -797,7 +797,7 @@ def haydavies(surface_tilt, surface_azimuth, dhi, dni, dni_extra,
             * poa_sky_diffuse: Total sky diffuse
             * poa_isotropic
             * poa_circumsolar
-        The model does not support a horizon brightening component.
+        The model does not include a horizon brightening component.
 
     Notes
     ------