diff --git a/doc/release_notes.rst b/doc/release_notes.rst
index 86763287..c20f1ebe 100644
--- a/doc/release_notes.rst
+++ b/doc/release_notes.rst
@@ -60,6 +60,8 @@ Upcoming Release
 * The rule ``plot_network`` has been split into separate rules for plotting
   electricity, hydrogen and gas networks.
 
+* To determine the optimal topology to meet the number of clusters, the workflow used pyomo in combination with ``ipopt`` or ``gurobi``. This dependency has been replaced by using ``linopy`` in combination with ``scipopt`` or ``gurobi``. The environment file has been updated accordingly.
+
 
 PyPSA-Eur 0.9.0 (5th January 2024)
 ==================================