diff --git a/src/reactor_sim/reactor.py b/src/reactor_sim/reactor.py
index 941dc7a..393793b 100644
--- a/src/reactor_sim/reactor.py
+++ b/src/reactor_sim/reactor.py
@@ -205,10 +205,14 @@ class Reactor:
         any_units = any(primary_units_active) or any(secondary_units_active) or any(self.turbine_unit_active)
         load_present = any_units or (self.consumer and self.consumer.online)
         idle_core = state.core.power_output_mw < 1.0 and self.control.rod_fraction >= 0.9
-        if (self.shutdown and not load_present and idle_core):
-            aux_base = 0.0
-        else:
-            aux_base = constants.BASE_AUX_LOAD_MW
+        baseline_off = (
+            (self.shutdown or idle_core)
+            and not load_present
+            and state.total_electrical_output() <= 0.01
+            and sum(primary_units_active) == 0
+            and sum(secondary_units_active) == 0
+        )
+        aux_base = 0.0 if baseline_off else constants.BASE_AUX_LOAD_MW
         aux_pump_primary = constants.PUMP_POWER_MW * sum(primary_units_active)
         aux_pump_secondary = constants.PUMP_POWER_MW * sum(secondary_units_active)
         aux_demand = aux_base + aux_pump_primary + aux_pump_secondary