diff --git a/84 Super Star Trek/csharp/Objects/Enterprise.cs b/84 Super Star Trek/csharp/Objects/Enterprise.cs
index 004ce893..bb177369 100644
--- a/84 Super Star Trek/csharp/Objects/Enterprise.cs	
+++ b/84 Super Star Trek/csharp/Objects/Enterprise.cs	
@@ -87,6 +87,11 @@ namespace SuperStarTrek.Objects
 
         public override string ToString() => "<*>";
 
+        internal void UseEnergy(float amountUsed)
+        {
+            TotalEnergy -= amountUsed;
+        }
+
         internal CommandResult TakeHit(Coordinates sector, int hitStrength)
         {
             _output.WriteLine($"{hitStrength} unit hit on Enterprise from sector {sector}");
diff --git a/84 Super Star Trek/csharp/Systems/PhaserControl.cs b/84 Super Star Trek/csharp/Systems/PhaserControl.cs
index 5aa7cf8b..18566294 100644
--- a/84 Super Star Trek/csharp/Systems/PhaserControl.cs	
+++ b/84 Super Star Trek/csharp/Systems/PhaserControl.cs	
@@ -42,6 +42,8 @@ namespace SuperStarTrek.Systems
             var phaserStrength = GetPhaserStrength();
             if (phaserStrength < 0) { return CommandResult.Ok; }
 
+            _enterprise.UseEnergy(phaserStrength);
+
             var perEnemyStrength = GetPerTargetPhaserStrength(phaserStrength, quadrant.KlingonCount);
 
             foreach (var klingon in quadrant.Klingons.ToList())