diff --git a/doc/release_notes.rst b/doc/release_notes.rst
index 9b1381ce5..c111e9bc1 100644
--- a/doc/release_notes.rst
+++ b/doc/release_notes.rst
@@ -39,6 +39,7 @@ Upcoming Release
 **Bugs and Compatibility**
 
 * A bug preventing custom powerplants specified in ``data/custom_powerplants.csv`` was fixed. (https://github.com/PyPSA/pypsa-eur/pull/732)
+* Fix nodal fraction in ``add_existing_year`` when using distributed generators
 
 
 PyPSA-Eur 0.8.1 (27th July 2023)
diff --git a/scripts/add_existing_baseyear.py b/scripts/add_existing_baseyear.py
index 1474b0042..1842166b8 100644
--- a/scripts/add_existing_baseyear.py
+++ b/scripts/add_existing_baseyear.py
@@ -88,7 +88,9 @@ def add_existing_renewables(df_agg):
             ]
             cfs = n.generators_t.p_max_pu[gens].mean()
             cfs_key = cfs / cfs.sum()
-            nodal_fraction.loc[n.generators.loc[gens, "bus"]] = cfs_key.values
+            nodal_fraction.loc[n.generators.loc[gens, "bus"]] = cfs_key.groupby(
+                n.generators.loc[gens, "bus"]
+            ).sum()
 
         nodal_df = df.loc[n.buses.loc[elec_buses, "country"]]
         nodal_df.index = elec_buses