diff --git a/pes_to_spec/model.py b/pes_to_spec/model.py
index 5e72e2d8fe03ee47466dc44d68cf8f19d98d92de..c635c373d5a0f8fdd07013560051920f76fba254 100644
--- a/pes_to_spec/model.py
+++ b/pes_to_spec/model.py
@@ -924,7 +924,7 @@ class Model(TransformerMixin, BaseEstimator):
 
         Returns: Total variance per channel.
         """
-        channels = list(low_res_data.keys())
+        channels = list(self.channel_pca.keys())
         return {ch: np.sum(self.channel_pca[ch].explained_variance_) for ch in channels}
 
     def check_compatibility(self, low_res_data: Dict[str, np.ndarray], pulse_spacing: Optional[Dict[str, List[int]]]=None, pulse_energy: Optional[np.ndarray]=None) -> np.ndarray: