diff --git a/core/src/mindustry/world/blocks/power/PowerGraph.java b/core/src/mindustry/world/blocks/power/PowerGraph.java
index abfdfbdaa3..6c179b4dc0 100644
--- a/core/src/mindustry/world/blocks/power/PowerGraph.java
+++ b/core/src/mindustry/world/blocks/power/PowerGraph.java
@@ -249,6 +249,8 @@ public class PowerGraph{
     }
 
     public void addGraph(PowerGraph graph){
+        if(graph == this) return;
+
         for(Building tile : graph.all){
             add(tile);
         }
@@ -283,9 +285,8 @@ public class PowerGraph{
             Building child = queue.removeFirst();
             add(child);
             for(Building next : child.getPowerConnections(outArray2)){
-                if(!closedSet.contains(next.pos())){
+                if(closedSet.add(next.pos())){
                     queue.addLast(next);
-                    closedSet.add(next.pos());
                 }
             }
         }
@@ -293,9 +294,6 @@ public class PowerGraph{
 
     public void remove(Building tile){
 
-        //begin by clearing the closed set
-        closedSet.clear();
-
         //go through all the connections of this tile
         for(Building other : tile.getPowerConnections(outArray1)){
             //a graph has already been assigned to this tile from a previous call, skip it
@@ -316,9 +314,9 @@ public class PowerGraph{
                 for(Building next : child.getPowerConnections(outArray2)){
                     //make sure it hasn't looped back, and that the new graph being assigned hasn't already been assigned
                     //also skip closed tiles
-                    if(next != tile && next.power.graph != graph && !closedSet.contains(next.pos())){
+                    if(next != tile && next.power.graph != graph){
+                        graph.add(next);
                         queue.addLast(next);
-                        closedSet.add(next.pos());
                     }
                 }
             }