Pow3r: stage 1 (#4208)

Co-authored-by: 20kdc <asdd2808@gmail.com>

Content.Server/Singularity/EntitySystems/EmitterSystem.cs

@@ -0,0 +1,38 @@
+using Content.Server.Power.EntitySystems;
+using Content.Server.Singularity.Components;
+using JetBrains.Annotations;
+using Robust.Shared.GameObjects;
+
+namespace Content.Server.Singularity.EntitySystems
+{
+    [UsedImplicitly]
+    public class EmitterSystem : EntitySystem
+    {
+        public override void Initialize()
+        {
+            base.Initialize();
+
+            SubscribeLocalEvent<EmitterComponent, PowerConsumerReceivedChanged>(ReceivedChanged);
+        }
+
+        private static void ReceivedChanged(
+            EntityUid uid,
+            EmitterComponent component,
+            PowerConsumerReceivedChanged args)
+        {
+            if (!component.IsOn)
+            {
+                return;
+            }
+
+            if (args.ReceivedPower < args.DrawRate)
+            {
+                component.PowerOff();
+            }
+            else
+            {
+                component.PowerOn();
+            }
+        }
+    }
+}