test: revert setting highs as default solver, as not available for macos

config/test/config.electricity.yaml

@@ -69,8 +69,8 @@ lines:
 
 solving:
   solver:
-    name: highs
-    options: "highs-default"
+    name: glpk
+    options: "glpk-default"
 
 
 plotting:

config/test/config.myopic.yaml

@@ -73,8 +73,8 @@ industry:
 
 solving:
   solver:
-    name: highs
-    options: highs-default
+    name: glpk
+    options: glpk-default
   mem: 4000
 
 plotting:

config/test/config.overnight.yaml

@@ -65,8 +65,8 @@ sector:
 
 solving:
   solver:
-    name: highs
-    options: highs-default
+    name: glpk
+    options: glpk-default
   mem: 4000
 
 plotting:

config/test/config.perfect.yaml

@@ -75,8 +75,8 @@ industry:
 
 solving:
   solver:
-    name: highs
-    options: highs-default
+    name: glpk
+    options: glpk-default
   mem: 4000
 
 plotting:

doc/release_notes.rst

@@ -64,8 +64,6 @@ Upcoming Release
 
 * The ``highs`` solver was added to the default environment file.
 
-* The default solver for testing the workflow in the CI has been changed from ``glpk`` to ``highs``.
-
 
 
 PyPSA-Eur 0.9.0 (5th January 2024)

envs/environment.yaml

@@ -35,6 +35,7 @@ dependencies:
 - netcdf4
 - networkx
 - scipy
+- glpk
 - shapely>=2.0
 - pyscipopt
 - matplotlib