Fix get_pvgis_tmy for outputformat='csv'

docs/sphinx/source/whatsnew/v0.11.3.rst

@@ -4,6 +4,12 @@
 v0.11.3 (Anticipated March, 2025)
 ---------------------------------
 
+Bug fixes
+~~~~~~~~~
+* :py:func:`~pvlib.iotools.get_pvgis_tmy` with ``outputformat='csv'`` now
+  works with the updated data format returned by PVGIS. (:issue:`2344`, :pull:`2395`)
+
+
 Deprecations
 ~~~~~~~~~~~~
 

pvlib/data/tmy_45.000_8.000_2005_2023.csv

@@ -1,6 +1,7 @@
 Latitude (decimal degrees): 45.000
 Longitude (decimal degrees): 8.000
 Elevation (m): 250.0
+Irradiance Time Offset (h): 0.1761
 month,year
 1,2018
 2,2007

pvlib/iotools/pvgis.py

@@ -559,9 +559,17 @@ def _parse_pvgis_tmy_csv(src):
     inputs['longitude'] = float(src.readline().split(b':')[1])
     # Elevation (m): 1389.0\r\n
     inputs['elevation'] = float(src.readline().split(b':')[1])
+
+    # TMY has an extra line here: Irradiance Time Offset (h): 0.1761\r\n
+    line = src.readline()
+    if line.startswith(b'Irradiance Time Offset'):
+        inputs['irradiance time offset'] = float(line.split(b':')[1])
+        src.readline()  # skip over the "month,year\r\n"
+    else:
+        # `line` is already the "month,year\r\n" line, so nothing to do
+        pass
     # then there's a 13 row comma separated table with two columns: month, year
-    # which contains the year used for that month in the
-    src.readline()  # get "month,year\r\n"
+    # which contains the year used for that month in the TMY
     months_selected = []
     for month in range(12):
         months_selected.append(

pvlib/tests/iotools/test_pvgis.py

@@ -321,7 +321,8 @@ def month_year_expected():
 @pytest.fixture
 def inputs_expected():
     return {
-        'location': {'latitude': 45.0, 'longitude': 8.0, 'elevation': 250.0},
+        'location': {'latitude': 45.0, 'longitude': 8.0, 'elevation': 250.0,
+                     'irradiance time offset': 0.1761},
         'meteo_data': {
             'radiation_db': 'PVGIS-SARAH3',
             'meteo_db': 'ERA5',
@@ -503,6 +504,9 @@ def _compare_pvgis_tmy_csv(expected, month_year_expected, inputs_expected,
     assert inputs['latitude'] == inputs_expected['location']['latitude']
     assert inputs['longitude'] == inputs_expected['location']['longitude']
     assert inputs['elevation'] == inputs_expected['location']['elevation']
+    assert (inputs['irradiance time offset']
+            == inputs_expected['location']['irradiance time offset']
+            )
     for meta_value in meta:
         if not meta_value:
             continue