diff --git a/hub/city_model_structure/building.py b/hub/city_model_structure/building.py
index 6aa29be0..42276a55 100644
--- a/hub/city_model_structure/building.py
+++ b/hub/city_model_structure/building.py
@@ -661,7 +661,7 @@ class Building(CityObject):
           for heating_demand_key in self.heating:
             _consumption = [0]*len(self.heating[heating_demand_key][cte.INSEL_MEB])
             _demand = self.heating[heating_demand_key][cte.INSEL_MEB]
-            for i in enumerate(_consumption):
+            for i, _ in enumerate(_consumption):
               _consumption[i] += (parasitic_energy_consumption + consumption_variable_flow) * _demand[i]
             self._distribution_systems_electrical_consumption[heating_demand_key] = _consumption
         if demand_type.lower() == cte.COOLING.lower():
@@ -670,7 +670,7 @@ class Building(CityObject):
           for demand_key in self.cooling:
             _consumption = self._distribution_systems_electrical_consumption[demand_key]
             _demand = self.cooling[demand_key][cte.INSEL_MEB]
-            for i in enumerate(_consumption):
+            for i, _ in enumerate(_consumption):
               _consumption[i] += (parasitic_energy_consumption + consumption_variable_flow) * _demand[i]
             self._distribution_systems_electrical_consumption[demand_key] = _consumption