diff --git a/scripts/add_existing_baseyear.py b/scripts/add_existing_baseyear.py
index 4e6f5dda..83ba91e4 100644
--- a/scripts/add_existing_baseyear.py
+++ b/scripts/add_existing_baseyear.py
@@ -272,9 +272,11 @@ def add_power_capacities_installed_before_baseyear(n, grouping_years, costs, bas
 
             # this is for the year 2020
             if not already_build.empty:
-                n.generators.loc[already_build, "p_nom_min"] = capacity.loc[
-                    already_build.str.replace(name_suffix, "")
-                ].values
+                n.generators.loc[already_build, "p_nom"] = \
+                n.generators.loc[already_build, "p_nom_min"] = \
+                    capacity.loc[
+                        already_build.str.replace(name_suffix, "")
+                    ].values
             new_capacity = capacity.loc[new_build.str.replace(name_suffix, "")]
 
             if "m" in snakemake.wildcards.clusters: