diff --git a/basic_machines/technic_power.lua b/basic_machines/technic_power.lua
index ec696a2..0b2c212 100644
--- a/basic_machines/technic_power.lua
+++ b/basic_machines/technic_power.lua
@@ -275,7 +275,7 @@ minetest.register_node("basic_machines:battery_0", {
 		insert_object = function(pos, node, stack, direction)
 			local meta = minetest.get_meta(pos)
 			local inv = meta:get_inventory()
-			return inv:add_item("fuel", stack)
+			return inv:add_item("upgrade", stack)
 		end,
 		can_insert = function(pos, node, stack, direction)
 			local meta = minetest.get_meta(pos)
@@ -283,9 +283,9 @@ minetest.register_node("basic_machines:battery_0", {
 			if meta:get_int("split_material_stacks") == 1 then
 				stack = stack:peek_item(1)
 			end
-			return inv:room_for_item("fuel", stack)
+			return inv:room_for_item("upgrade", stack)
 		end,
-		input_inventory = "upgrade",
+		input_inventory = "fuel",
 		connect_sides = {left = 1, right = 1, back = 1, front = 1, bottom = 1, top = 1}
 	},
 })
@@ -410,7 +410,7 @@ minetest.register_node("basic_machines:generator", {
 		insert_object = function(pos, node, stack, direction)
 			local meta = minetest.get_meta(pos)
 			local inv = meta:get_inventory()
-			return inv:add_item("fuel", stack)
+			return inv:add_item("upgrade", stack)
 		end,
 		can_insert = function(pos, node, stack, direction)
 			local meta = minetest.get_meta(pos)
@@ -418,9 +418,9 @@ minetest.register_node("basic_machines:generator", {
 			if meta:get_int("split_material_stacks") == 1 then
 				stack = stack:peek_item(1)
 			end
-			return inv:room_for_item("fuel", stack)
+			return inv:room_for_item("upgrade", stack)
 		end,
-		input_inventory = "upgrade",
+		input_inventory = "fuel",
 		connect_sides = {left = 1, right = 1, back = 1, front = 1, bottom = 1, top = 1}
 	},
 })