diff --git a/CHANGELOG.md b/CHANGELOG.md
index a0a181b69..f4ec4983c 100644
--- a/CHANGELOG.md
+++ b/CHANGELOG.md
@@ -89,6 +89,7 @@
 * Fixed #2414
 * Fixed #2454
 * Fixed #2457
+* Fixed #2411
 
 ## Release Candidate 16 (07 Sep 2020)
 https://thebusybiscuit.github.io/builds/TheBusyBiscuit/Slimefun4/stable/#16
diff --git a/src/main/java/io/github/thebusybiscuit/slimefun4/implementation/items/electric/AbstractEnergyProvider.java b/src/main/java/io/github/thebusybiscuit/slimefun4/implementation/items/electric/AbstractEnergyProvider.java
index cc16f0db6..b7767796b 100644
--- a/src/main/java/io/github/thebusybiscuit/slimefun4/implementation/items/electric/AbstractEnergyProvider.java
+++ b/src/main/java/io/github/thebusybiscuit/slimefun4/implementation/items/electric/AbstractEnergyProvider.java
@@ -8,6 +8,7 @@ import java.util.Set;
 import javax.annotation.Nonnull;
 import javax.annotation.ParametersAreNonnullByDefault;
 
+import org.apache.commons.lang.Validate;
 import org.bukkit.inventory.Inventory;
 import org.bukkit.inventory.ItemStack;
 import org.bukkit.inventory.meta.ItemMeta;
@@ -89,11 +90,12 @@ public abstract class AbstractEnergyProvider extends SlimefunItem implements Inv
     }
 
     public void registerFuel(@Nonnull MachineFuel fuel) {
+        Validate.notNull(fuel, "Machine Fuel cannot be null!");
         fuelTypes.add(fuel);
     }
 
     @Nonnull
-    public Set<MachineFuel> getFuelTypes() {
+    public Set<MachineFuel> getFuelTypes2() {
         return fuelTypes;
     }
 
diff --git a/src/main/java/io/github/thebusybiscuit/slimefun4/implementation/items/electric/generators/CoalGenerator.java b/src/main/java/io/github/thebusybiscuit/slimefun4/implementation/items/electric/generators/CoalGenerator.java
index 1f0499a61..886164817 100644
--- a/src/main/java/io/github/thebusybiscuit/slimefun4/implementation/items/electric/generators/CoalGenerator.java
+++ b/src/main/java/io/github/thebusybiscuit/slimefun4/implementation/items/electric/generators/CoalGenerator.java
@@ -74,7 +74,7 @@ public abstract class CoalGenerator extends AGenerator {
         }
 
         // Signs
-        for (Material mat : Tag.SIGNS.getValues()) {
+        for (Material mat : Tag.STANDING_SIGNS.getValues()) {
             registerFuel(new MachineFuel(2, new ItemStack(mat)));
         }
     }