add optional function to restore transmission connections to Crimea

config/config.default.yaml

@@ -240,6 +240,7 @@ lines:
   s_nom_max: .inf
   max_extension: .inf
   length_factor: 1.25
+  reconnect_crimea: true
   under_construction: 'zero' # 'zero': set capacity to zero, 'remove': remove, 'keep': with full capacity
   dynamic_line_rating:
     activate: false

scripts/base_network.py

@@ -368,6 +368,22 @@ def _apply_parameter_corrections(n, parameter_corrections):
                 df.loc[inds, attr] = r[inds].astype(df[attr].dtype)
 
 
+def _reconnect_crimea(lines):
+    logger.info("Reconnecting Crimea to the Ukrainian grid.")
+    lines_to_crimea = pd.DataFrame({
+        "bus0": ["3065", "3181", "3181"],
+        "bus1": ["3057", "3055", "3057"],
+        "v_nom": [300, 300, 300],
+        "num_parallel": [1, 1, 1],
+        "length": [140, 120, 140],
+        "carrier": ["AC", "AC", "AC"],
+        "underground": [False, False, False],
+        "under_construction": [False, False, False],
+    }, index=["Melitopol", "Liubymivka left", "Luibymivka right"])
+
+    return pd.concat([lines, lines_to_crimea])
+
+
 def _set_electrical_parameters_lines(lines, config):
     v_noms = config["electricity"]["voltages"]
     linetypes = config["lines"]["types"]
@@ -705,6 +721,9 @@ def base_network(
     lines = _load_lines_from_eg(buses, eg_lines)
     transformers = _load_transformers_from_eg(buses, eg_transformers)
 
+    if config["lines"].get("reconnect_crimea", True) and "UA" in config["countries"]:
+        lines = _reconnect_crimea(lines)
+
     lines = _set_electrical_parameters_lines(lines, config)
     transformers = _set_electrical_parameters_transformers(transformers, config)
     links = _set_electrical_parameters_links(links, config, links_p_nom)