diff --git a/src/reactor_sim/reactor.py b/src/reactor_sim/reactor.py
index c7ab3bb..6dd3ab4 100644
--- a/src/reactor_sim/reactor.py
+++ b/src/reactor_sim/reactor.py
@@ -203,8 +203,8 @@ class Reactor:
             for idx in range(2)
         ]
         any_units = any(primary_units_active) or any(secondary_units_active) or any(self.turbine_unit_active)
-        any_generators = any(getattr(g, "running", False) or getattr(g, "starting", False) for g in state.generators)
-        aux_base = 0.0 if (self.shutdown and not any_units and not any_generators) else constants.BASE_AUX_LOAD_MW
+        load_present = any_units or (self.consumer and self.consumer.online)
+        aux_base = constants.BASE_AUX_LOAD_MW if not self.shutdown or load_present else 0.0
         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
@@ -566,6 +566,11 @@ class Reactor:
                     GeneratorState(running=False, starting=False, spool_remaining=0.0, power_output_mw=0.0, battery_charge=1.0)
                 )
         deficit = max(0.0, aux_demand - turbine_electric)
+        if self.generator_auto and aux_demand <= 0.0:
+            for idx, gen_state in enumerate(state.generators):
+                if gen_state.running or gen_state.starting:
+                    self.generators[idx].stop(gen_state)
+            return 0.0
         if self.generator_auto:
             if deficit > 0.0:
                 for idx, gen_state in enumerate(state.generators):