diff --git a/biofuel-manager.lua b/biofuel-manager.lua
index 2a899e5..f9ee1d2 100644
--- a/biofuel-manager.lua
+++ b/biofuel-manager.lua
@@ -110,9 +110,35 @@ local stock = {
     end,
 }
 
+function listItems (storage)
+    local tally = {}
+    for _, item in pairs(peripheral.call(storage, "list")) do
+        if tally[item.name] == nil then tally[item.name] = 0 end
+        tally[item.name] = tally[item.name] + item.count
+    end
+    return tally
+end
 
 function getOrders ()
-    -- TODO
+    local orders = {}
+    -- Oil
+    local oil_amt = table.remove(peripheral.call(OIL_TANK, "tanks"))
+    if oil_amt == nil then oil_amt = 0 end
+    local oil_needed = OIL_SETPOINT - oil_amt
+    if oil_needed > 0 then orders.oil = oil_needed end
+    -- Biomass
+    -- TODO use up excess material
+    local biomass_amt = listItems(STORAGE)["createaddition:biomass"]
+    if biomass_amt == nil then biomass_amt = 0 end
+    local biomass_needed = BIOMASS_SETPOINT - biomass_amt
+    if biomass_needed > 0 then orders.biomass = biomass_needed end
+    -- Biofuel
+    -- TODO use up excess material?
+    local biofuel_amt = table.remove(peripheral.call(FUEL_TANK, "tanks"))
+    if biofuel_amt == nil then biofuel_amt = 0 end
+    local biofuel_needed = BIOFUEL_SETPOINT - biofuel_amt
+    if biofuel_needed > 0 then orders.biofuel = biofuel_needed end
+    return orders
 end
 
 function run (ticker)