diff --git a/scripts/make_summary.py b/scripts/make_summary.py
index fb13e91e..9da915ef 100644
--- a/scripts/make_summary.py
+++ b/scripts/make_summary.py
@@ -522,8 +522,8 @@ def calculate_weighted_prices(n, label, weighted_prices):
             if not names.empty:
                 load += (
                     n.links_t.p0[names]
-                    .groupby(n.links.loc[names, "bus0"], axis=1)
-                    .sum()
+                    .T.groupby(n.links.loc[names, "bus0"])
+                    .sum().T
                 )
 
         # Add H2 Store when charging
@@ -560,14 +560,13 @@ def calculate_market_values(n, label, market_values):
 
     for tech in techs:
         gens = generators[n.generators.loc[generators, "carrier"] == tech]
-
+        
         dispatch = (
             n.generators_t.p[gens]
-            .groupby(n.generators.loc[gens, "bus"], axis=1)
-            .sum()
+            .T.groupby(n.generators.loc[gens, "bus"])
+            .sum().T
             .reindex(columns=buses, fill_value=0.0)
         )
-
         revenue = dispatch * n.buses_t.marginal_price[buses]
 
         market_values.at[tech, label] = revenue.sum().sum() / dispatch.sum().sum()
@@ -586,8 +585,8 @@ def calculate_market_values(n, label, market_values):
 
             dispatch = (
                 n.links_t["p" + i][links]
-                .groupby(n.links.loc[links, "bus" + i], axis=1)
-                .sum()
+                .T.groupby(n.links.loc[links, "bus" + i])
+                .sum().T
                 .reindex(columns=buses, fill_value=0.0)
             )
 
diff --git a/scripts/plot_summary.py b/scripts/plot_summary.py
index 67ac9b55..e0067d7f 100644
--- a/scripts/plot_summary.py
+++ b/scripts/plot_summary.py
@@ -154,7 +154,7 @@ def plot_costs():
 
     df = df.drop(to_drop)
 
-    logger.info(f"Total system cost of {round(df.sum()[0])} EUR billion per year")
+    logger.info(f"Total system cost of {round(df.sum().iloc[0])} EUR billion per year")
 
     new_index = preferred_order.intersection(df.index).append(
         df.index.difference(preferred_order)
@@ -214,7 +214,7 @@ def plot_energy():
 
     df = df.drop(to_drop)
 
-    logger.info(f"Total energy of {round(df.sum()[0])} TWh/a")
+    logger.info(f"Total energy of {round(df.sum().iloc[0])} TWh/a")
 
     if df.empty:
         fig, ax = plt.subplots(figsize=(12, 8))
@@ -304,7 +304,7 @@ def plot_balances():
 
         df = df.drop(to_drop)
 
-        logger.debug(f"Total energy balance for {v} of {round(df.sum()[0],2)} {units}")
+        logger.debug(f"Total energy balance for {v} of {round(df.sum().iloc[0],2)} {units}")
 
         if df.empty:
             continue