diff --git a/tardis/spectrum/base.py b/tardis/spectrum/base.py
index 2780e893783..e7b872ff759 100644
--- a/tardis/spectrum/base.py
+++ b/tardis/spectrum/base.py
@@ -99,14 +99,12 @@ def spectrum_integrated(self):
                     "This RETURNS AN EMPTY SPECTRUM!",
                     UserWarning,
                 )
-                return TARDISSpectrum(
+                self._spectrum_integrated = TARDISSpectrum(
                     np.array([np.nan, np.nan]) * u.Hz,
                     np.array([np.nan]) * u.erg / u.s,
                 )
-        else:
-            self._spectrum_integrated = None
         return self._spectrum_integrated
-
+    
     @property
     def integrator(self):
         if self._integrator is None:
diff --git a/tardis/tests/test_tardis_full_formal_integral.py b/tardis/tests/test_tardis_full_formal_integral.py
index 985168baf95..fb9fe746a40 100644
--- a/tardis/tests/test_tardis_full_formal_integral.py
+++ b/tardis/tests/test_tardis_full_formal_integral.py
@@ -86,9 +86,9 @@ def test_spectrum(self, simulation, request):
       expected = u.Quantity(expected, "erg /s")
       assert_quantity_allclose(luminosity, expected)
 
-#   def test_spectrum_integrated(self, simulation, request):
-#       regression_data = RegressionData(request)
-#       luminosity = simulation.spectrum_solver.spectrum_integrated.luminosity
-#       expected = regression_data.sync_ndarray(luminosity.cgs.value)
-#       expected = u.Quantity(expected, "erg /s")
-#       assert_quantity_allclose(luminosity, expected)
\ No newline at end of file
+  def test_spectrum_integrated(self, simulation, request):
+      regression_data = RegressionData(request)
+      luminosity = simulation.spectrum_solver.spectrum_integrated.luminosity
+      expected = regression_data.sync_ndarray(luminosity.cgs.value)
+      expected = u.Quantity(expected, "erg /s")
+      assert_quantity_allclose(luminosity, expected)
\ No newline at end of file