diff --git a/config/config.default.yaml b/config/config.default.yaml
index 34117f1d..50ef03d6 100644
--- a/config/config.default.yaml
+++ b/config/config.default.yaml
@@ -85,7 +85,7 @@ co2_budget:
 
 # docs in https://pypsa-eur.readthedocs.io/en/latest/configuration.html#electricity
 electricity:
-  voltages: [220., 300., 380., 750.]
+  voltages: [220., 300., 380., 500., 750.]
   gaslimit: false
   co2limit: 9.59e+7
   co2base: 1.918e+9
@@ -234,6 +234,7 @@ lines:
     220.: "Al/St 240/40 2-bundle 220.0"
     300.: "Al/St 240/40 3-bundle 300.0"
     380.: "Al/St 240/40 4-bundle 380.0"
+    500.: "Al/St 240/40 4-bundle 380.0"
     750.: "Al/St 560/50 4-bundle 750.0"
   s_max_pu: 0.7
   s_nom_max: .inf