diff --git a/hub/city_model_structure/building.py b/hub/city_model_structure/building.py
index cbbda322..8c7fbae7 100644
--- a/hub/city_model_structure/building.py
+++ b/hub/city_model_structure/building.py
@@ -759,21 +759,23 @@ class Building(CityObject):
         if demand_type.lower() == consumption_type.lower():
           if consumption_type in (cte.HEATING, cte.DOMESTIC_HOT_WATER):
             for generation_system in energy_system_generation_systems:
-              coefficient_of_performance = generation_system.generic_generation_system[0].heat_efficiency
+              generic_gen = generation_system.generic_generation_system
+              print(generation_system)
+              coefficient_of_performance = generation_system.generic_generation_system.heat_efficiency
           elif consumption_type == cte.COOLING:
             for generation_system in energy_system_generation_systems:
-              coefficient_of_performance = generation_system.generic_generation_system[0].cooling_efficiency
+              coefficient_of_performance = generation_system.generic_generation_system.cooling_efficiency
           elif consumption_type == cte.ELECTRICITY:
             for generation_system in energy_system_generation_systems:
               coefficient_of_performance = \
-                generation_system.generic_generation_system[0].electricity_efficiency
+                generation_system.generic_generation_system.electricity_efficiency
     if coefficient_of_performance == 0:
       values = [0] * len(demand)
       final_energy_consumed = values
     else:
       final_energy_consumed = []
       for demand_value in demand:
-        final_energy_consumed.append(demand_value / coefficient_of_performance)
+        final_energy_consumed.append(demand_value / float(coefficient_of_performance))
     return final_energy_consumed
 
   @property
@@ -799,8 +801,8 @@ class Building(CityObject):
     for energy_system in self.energy_systems:
       energy_system_generation_systems = energy_system.generation_systems
       for generation_system in energy_system_generation_systems:
-        if generation_system.generic_generation_system[0].type == cte.PHOTOVOLTAIC:
-          _efficiency = generation_system.generic_generation_system[0].electricity_efficiency
+        if generation_system.generic_generation_system.type == cte.PHOTOVOLTAIC:
+          _efficiency = generation_system.generic_generation_system.electricity_efficiency
           self._onsite_electrical_production = {}
           for _key in self.roofs[0].global_irradiance.keys():
             _results = [0 for _ in range(0, len(self.roofs[0].global_irradiance[_key]))]
diff --git a/tests/test_systems_factory.py b/tests/test_systems_factory.py
index f2e3a7b4..69cedd55 100644
--- a/tests/test_systems_factory.py
+++ b/tests/test_systems_factory.py
@@ -26,10 +26,12 @@ from hub.city_model_structure.energy_systems.distribution_system import Distribu
 from hub.city_model_structure.energy_systems.emission_system import EmissionSystem
 from hub.city_model_structure.energy_systems.thermal_storage_system import ThermalStorageSystem
 
+
 class TestSystemsFactory(TestCase):
   """
   TestSystemsFactory TestCase
   """
+
   def setUp(self) -> None:
     """
     Test setup
@@ -163,22 +165,20 @@ class TestSystemsFactory(TestCase):
           _building_generation_systems = _generic_building_energy_system.generation_systems
           _generic_system_generation_systems = []
           for _building_generation_system in _building_generation_systems:
-            _building_generation_system = GenerationSystem()
-            _building_generation_system.generic_generation_system = (
-              copy.deepcopy(_generic_building_energy_system.generation_systems)
+            _generation_system = GenerationSystem()
+            _generation_system.generic_generation_system = (
+              copy.deepcopy(_building_generation_system)
             )
-            _building_storage_system = ThermalStorageSystem()
-            _building_storage_system.generic_storage_system = \
-              copy.deepcopy(_generic_building_energy_system.energy_storage_systems)
-
             if cte.HEATING in _building_energy_equipment.demand_types:
-              _building_generation_system.heat_power = building.heating_peak_load[cte.YEAR][0]
+              _generation_system.heat_power = building.heating_peak_load[cte.YEAR][0]
             if cte.COOLING in _building_energy_equipment.demand_types:
-              _building_generation_system.cooling_power = building.cooling_peak_load[cte.YEAR][0]
-            _generic_system_generation_systems.append(_building_generation_system)
+              _generation_system.cooling_power = building.cooling_peak_load[cte.YEAR][0]
+            _generic_system_generation_systems.append(_generation_system)
           print(_generic_system_generation_systems)
           _building_energy_equipment.generation_systems = _generic_system_generation_systems
-
+          _building_storage_system = ThermalStorageSystem()
+          _building_storage_system.generic_storage_system = \
+            copy.deepcopy(_generic_building_energy_system.energy_storage_systems)
           _building_energy_systems.append(_building_energy_equipment)
       building.energy_systems = _building_energy_systems
 
@@ -188,6 +188,6 @@ class TestSystemsFactory(TestCase):
       print(building.domestic_hot_water_consumption[cte.YEAR][0])
       print(building.onsite_electrical_production[cte.YEAR][0])
       self.assertLess(0, building.heating_consumption[cte.YEAR][0])
-      self.assertLess(0, building.cooling_consumption[cte.YEAR][0])
+      self.assertEqual(0, building.cooling_consumption[cte.YEAR][0])
       self.assertLess(0, building.domestic_hot_water_consumption[cte.YEAR][0])
-      self.assertLess(0, building.onsite_electrical_production[cte.YEAR][0])
\ No newline at end of file
+      self.assertLess(0, building.onsite_electrical_production[cte.YEAR][0])