cluster_network: allow more solvers that can handle quadratic problems

doc/release_notes.rst

@@ -10,6 +10,8 @@ Release Notes
 Upcoming Release
 ================
 
+* Allow the use of more solvers in clustering (Xpress, COPT, Gurobi, CPLEX, SCIP, MOSEK).
+
 * Enhanced support for choosing different weather years
   (https://github.com/PyPSA/pypsa-eur/pull/204):
 

scripts/cluster_network.py

@@ -267,7 +267,7 @@ def distribute_clusters(n, n_clusters, focus_weights=None, solver_name="scip"):
     m.objective = (clusters * clusters - 2 * clusters * L * n_clusters).sum()
     if solver_name == "gurobi":
         logging.getLogger("gurobipy").propagate = False
-    elif solver_name not in ["scip", "cplex"]:
+    elif solver_name not in ["scip", "cplex", "xpress", "copt", "mosek"]:
         logger.info(
             f"The configured solver `{solver_name}` does not support quadratic objectives. Falling back to `scip`."
         )