diff --git a/rules/build_electricity.smk b/rules/build_electricity.smk
index 65e24189..ed341d2f 100644
--- a/rules/build_electricity.smk
+++ b/rules/build_electricity.smk
@@ -487,7 +487,6 @@ rule simplify_network:
         regions_onshore=resources("regions_onshore_elec_s{simpl}.geojson"),
         regions_offshore=resources("regions_offshore_elec_s{simpl}.geojson"),
         busmap=resources("busmap_elec_s{simpl}.csv"),
-        connection_costs=resources("connection_costs_s{simpl}.csv"),
     log:
         logs("simplify_network/elec_s{simpl}.log"),
     benchmark:
diff --git a/scripts/build_electricity_demand.py b/scripts/build_electricity_demand.py
index 9174672d..7615bbc6 100755
--- a/scripts/build_electricity_demand.py
+++ b/scripts/build_electricity_demand.py
@@ -311,6 +311,8 @@ if __name__ == "__main__":
         logger.info("Supplement missing data with synthetic data.")
         fn = snakemake.input.synthetic
         synthetic_load = pd.read_csv(fn, index_col=0, parse_dates=True)
+        # "UA" does not appear in synthetic load data
+        countries = list(set(countries) - set(["UA"]))
         synthetic_load = synthetic_load.loc[snapshots, countries]
         load = load.combine_first(synthetic_load)
 
diff --git a/scripts/simplify_network.py b/scripts/simplify_network.py
index f129945c..8f2a84cd 100644
--- a/scripts/simplify_network.py
+++ b/scripts/simplify_network.py
@@ -209,7 +209,7 @@ def _compute_connection_costs_to_bus(
     return connection_costs_to_bus
 
 
-def _adjust_capital_costs_using_connection_costs(n, connection_costs_to_bus, output):
+def _adjust_capital_costs_using_connection_costs(n, connection_costs_to_bus):
     connection_costs = {}
     for tech in connection_costs_to_bus:
         tech_b = n.generators.carrier == tech
@@ -230,14 +230,12 @@ def _adjust_capital_costs_using_connection_costs(n, connection_costs_to_bus, out
                 )
             )
             connection_costs[tech] = costs
-    pd.DataFrame(connection_costs).to_csv(output.connection_costs)
 
 
 def _aggregate_and_move_components(
     n,
     busmap,
     connection_costs_to_bus,
-    output,
     aggregate_one_ports={"Load", "StorageUnit"},
     aggregation_strategies=dict(),
     exclude_carriers=None,
@@ -250,7 +248,7 @@ def _aggregate_and_move_components(
             if not df.empty:
                 import_series_from_dataframe(n, df, c, attr)
 
-    _adjust_capital_costs_using_connection_costs(n, connection_costs_to_bus, output)
+    _adjust_capital_costs_using_connection_costs(n, connection_costs_to_bus)
 
     generator_strategies = aggregation_strategies["generators"]
 
@@ -283,7 +281,6 @@ def simplify_links(
     length_factor,
     p_max_pu,
     exclude_carriers,
-    output,
     aggregation_strategies=dict(),
 ):
     ## Complex multi-node links are folded into end-points
@@ -408,7 +405,6 @@ def simplify_links(
         n,
         busmap,
         connection_costs_to_bus,
-        output,
         aggregation_strategies=aggregation_strategies,
         exclude_carriers=exclude_carriers,
     )
@@ -421,7 +417,6 @@ def remove_stubs(
     renewable_carriers,
     length_factor,
     simplify_network,
-    output,
     aggregation_strategies=dict(),
 ):
     logger.info("Removing stubs")
@@ -438,7 +433,6 @@ def remove_stubs(
         n,
         busmap,
         connection_costs_to_bus,
-        output,
         aggregation_strategies=aggregation_strategies,
         exclude_carriers=simplify_network["exclude_carriers"],
     )
@@ -558,7 +552,6 @@ if __name__ == "__main__":
         params.length_factor,
         params.p_max_pu,
         params.simplify_network["exclude_carriers"],
-        snakemake.output,
         params.aggregation_strategies,
     )
 
@@ -571,7 +564,6 @@ if __name__ == "__main__":
             params.renewable_carriers,
             params.length_factor,
             params.simplify_network,
-            snakemake.output,
             aggregation_strategies=params.aggregation_strategies,
         )
         busmaps.append(stub_map)