diff --git a/gspconsumer/app.py b/gspconsumer/app.py
index 0f9da64..5fbffc2 100644
--- a/gspconsumer/app.py
+++ b/gspconsumer/app.py
@@ -24,6 +24,7 @@
 from gspconsumer.backup import make_gsp_yields_from_national
 from gspconsumer.gsps import filter_gsps_which_have_new_data, get_gsps
 from gspconsumer.time import check_uk_london_hour
+from gspconsumer.nitghtime import make_night_time_zeros
 
 logging.basicConfig(
     level=getattr(logging, os.getenv("LOGLEVEL", "DEBUG")),
@@ -181,6 +182,12 @@ def pull_data_and_save(
 
         logger.debug(f"Got {len(gsp_yield_df)} gsp yield for gsp id {gsp.gsp_id} before filtering")
 
+        if len(gsp_yield_df) == 0:
+            logger.warning(f"Did not find any data for {gsp.gsp_id} for {start} to {end}. "
+                           f"Will try adding some nighttime zeros")
+
+            gsp_yield_df = make_night_time_zeros(start, end, gsp, gsp_yield_df, regime)
+
         if len(gsp_yield_df) == 0:
             logger.warning(f"Did not find any data for {gsp.gsp_id} for {start} to {end}")
         else:
diff --git a/gspconsumer/nitghtime.py b/gspconsumer/nitghtime.py
new file mode 100644
index 0000000..6affc70
--- /dev/null
+++ b/gspconsumer/nitghtime.py
@@ -0,0 +1,74 @@
+import pandas as pd
+import pvlib
+import os
+import logging
+from datetime import datetime
+
+from nowcasting_datamodel.models.gsp import LocationSQL
+
+logger = logging.getLogger(__name__)
+
+elevation_limit = os.getenv("ELEVATION_LIMIT", 5)
+
+# get lat and longs of the gsps
+dir = os.path.dirname(__file__)
+gsp_locations_file = os.path.join(dir, "data/uk_gsp_locations.csv")
+gsp_locations = pd.read_csv(gsp_locations_file)
+gsp_locations = gsp_locations.set_index("gsp_id")
+
+
+
+def make_night_time_zeros(
+    start: datetime,
+    end: datetime,
+    gsp: LocationSQL,
+    gsp_yield_df: pd.DataFrame,
+    regime: str,
+):
+    """
+    Set generation to zero if it is night time
+    
+    :param start: The start datetimes we are looking for
+    :param end: The end datetimes we are looking for
+    :param gsp:
+    :param gsp_yield_df: 
+    :param regime: 
+    :return: 
+    """
+    
+    if regime != "in-day":
+        return gsp_yield_df
+    
+    gsp_location = gsp_locations.loc[gsp.gsp_id]
+    longitude = gsp_location["longitude"]
+    latitude = gsp_location["latitude"]
+    
+    times = pd.date_range(start=start, end=end, freq="30min")
+    # check if it is nighttime, and if so, set generation values to zero
+    solpos = pvlib.solarposition.get_solarposition(
+        time=times, longitude=longitude, latitude=latitude, method="nrel_numpy"
+    )
+    elevation = solpos["elevation"]
+    
+    # only keep nighttime values
+    elevation = elevation[elevation < elevation_limit]
+    
+    # last capacity is
+    if gsp.last_gsp_yield is not None:
+        last_capacity = gsp.last_gsp_yield.capacity_mwp
+        last_pvlive_updated_utc = gsp.last_gsp_yield.pvlive_updated_utc
+    else:
+        last_capacity = 0
+        last_pvlive_updated_utc = start
+
+    gsp_yield_df = pd.DataFrame(
+        {
+            "generation_mw": 0,
+            "datetime_gmt": elevation.index,
+            "installedcapacity_mwp": last_capacity,
+            "capacity_mwp": last_capacity,
+            "updated_gmt": last_pvlive_updated_utc,
+        }
+    )
+    
+    return gsp_yield_df
diff --git a/requirements.txt b/requirements.txt
index b7cae9a..c1e282d 100644
--- a/requirements.txt
+++ b/requirements.txt
@@ -8,3 +8,4 @@ nowcasting_datamodel==1.5.46
 sentry-sdk==2.13.0
 #git+https://github.com/SheffieldSolar/PV_Live-API#pvlive_api
 click
+pvlib
diff --git a/tests/test_app.py b/tests/test_app.py
index b949672..429e680 100644
--- a/tests/test_app.py
+++ b/tests/test_app.py
@@ -33,6 +33,25 @@ def test_pull_data(db_session, input_data_last_updated_sql):
     assert gsps[0].installed_capacity_mw != 10
 
 
+# need to make this tomorrows date
+@freeze_time("2024-12-07 02:00:00")
+def test_pull_data_night_time(db_session):
+    gsps = [
+        Location(gsp_id=1, label="GSP_1", installed_capacity_mw=10).to_orm(),
+    ]
+    gsps[0].last_gsp_yield = None
+
+    pull_data_and_save(gsps=gsps, session=db_session)
+
+    pv_yields = db_session.query(GSPYieldSQL).all()
+    assert len(pv_yields) > 0
+    assert pv_yields[0].pvlive_updated_utc != None
+    assert pv_yields[0].capacity_mwp != None
+    assert pv_yields[0].solar_generation_kw == 0
+
+
+
+
 def test_app(db_connection, input_data_last_updated_sql):
     make_national(db_connection)