Balance generator load sharing

src/reactor_sim/reactor.py

@@ -562,8 +562,10 @@ class Reactor:
 
         total_power = 0.0
         remaining = max(0.0, aux_demand - turbine_electric)
+        active_indices = [idx for idx, g in enumerate(state.generators) if g.running or g.starting]
+        share = remaining / len(active_indices) if active_indices and remaining > 0 else 0.0
         for idx, gen_state in enumerate(state.generators):
-            load = remaining if remaining > 0 else 0.0
+            load = share if idx in active_indices else 0.0
             delivered = self.generators[idx].step(gen_state, load, dt)
             total_power += delivered
             remaining = max(0.0, remaining - delivered)