diff --git a/ocf_ml_metrics/evaluation/evaluation.py b/ocf_ml_metrics/evaluation/evaluation.py
index 3d7b456..de09685 100644
--- a/ocf_ml_metrics/evaluation/evaluation.py
+++ b/ocf_ml_metrics/evaluation/evaluation.py
@@ -13,7 +13,7 @@ def evaluation(
     results_df: pd.DataFrame,
     model_name: str,
     sun_threshold_degrees_for_night: float = -5.0,
-    error_thresholds: Union[float, int, list] = [1000, 2000],
+    error_thresholds: Union[float, int, list] = None,
     outturn_unit: str = "mw",
     **kwargs,
 ) -> dict:
@@ -45,6 +45,8 @@ def evaluation(
 
     """
     # make sure datetimes columns datetimes and floor target time t to nearest 5-minutes
+    if error_thresholds is None:
+        error_thresholds = [1000, 2000]
     results_df["t0_datetime_utc"] = pd.to_datetime(results_df["t0_datetime_utc"])
     results_df["target_datetime_utc"] = pd.to_datetime(results_df["target_datetime_utc"])
     results_df["target_datetime_utc"] = results_df["target_datetime_utc"].dt.floor("5T")
@@ -164,7 +166,7 @@ def evaluation_per_id(
     results_df: pd.DataFrame,
     model_name: str,
     sun_threshold_degrees_for_night: float = -5.0,
-    error_thresholds: Union[float, int, list] = [1000, 2000],
+    error_thresholds: Union[float, int, list] = None,
     outturn_unit: str = "mw",
     **kwargs,
 ) -> dict:
@@ -196,6 +198,8 @@ def evaluation_per_id(
 
     """
     # make sure datetimes columns datetimes and floor target time t to nearest 5-minutes
+    if error_thresholds is None:
+        error_thresholds = [1000, 2000]
     results_df["t0_datetime_utc"] = pd.to_datetime(results_df["t0_datetime_utc"])
     results_df["target_datetime_utc"] = pd.to_datetime(results_df["target_datetime_utc"])
     results_df["target_datetime_utc"] = results_df["target_datetime_utc"].dt.floor("5T")