The Headlines
Everything on Arrakis runs on water. These are the numbers that matter.
25 L
of water from ONE corpse in a Fremen Deathstill — 45 L in the Advanced. The single biggest water source in the game.
3×
more water per watt from a Deathstill (125–154 mL/Wh) than from Windtraps (38–48 mL/Wh)
2×
water from the same blood with the Improved Blood Purifier (40% vs 20% extraction)
75 L
of water consumed by ONE Large Spice Refinery batch (200 melange)
Water Production
Two families: Windtraps run hands-free forever; Deathstills need corpses but massively out-produce them.
Output — litres per hour (deathstills assume continuous feeding)
Power efficiency — mL of water per watt-hour — higher is better
| Source | Rate | Power | mL / watt-hour | Fuel |
|---|---|---|---|---|
| Windtrap | 0.8 mL/s · 2.88 L/hr | 75 W | 38.4 | none — passive |
| Large Windtrap | 1.8 mL/s · 6.48 L/hr | 135 W | 48.0 | none — passive |
| Fremen Deathstill | 25,000 mL / corpse / 60 min | 200 W | 125 | corpses |
| Advanced Fremen Deathstill | 45,000 mL / corpse / 50 min | 350 W | 154 | corpses |
Windtrap upgrade verdict: the Large Windtrap gives 2.25× the water for 1.8× the power —
25% more water per watt, and one build slot instead of two-and-a-quarter. Always upgrade.
Deathstill upgrade verdict: the Advanced yields +80% per corpse (45L vs 25L) and processes 20% faster.
If you PvE at all, a deathstill turns your combat loot into the best water economy in the game.
Blood Purification
The early-game path: extract blood from corpses with a handheld Blood Extractor, then filter it into usable water.
| Station | Extraction efficiency | Filtration rate | Power | Internal tank |
|---|---|---|---|---|
| Blood Purifier | 20% | 5 blood/s | 10 W | 1,000 mL |
| Improved Blood Purifier | 40% | 8 blood/s | 35 W | 1,000 mL |
The Improved model returns twice the water from every unit of blood and filters 60% faster.
Blood you process in the basic purifier is literally half-wasted — upgrade before you farm.
(Blood volume per corpse isn't reliably documented; the efficiency ratio is the dependable number here.)
Where the Water Goes
Refining is the big drinker — and the bill scales hard with material tier.
Water per refined unit (mL) — ore at Medium/Large refinery; melange by refinery tier
| Running non-stop… | Demand | = Large Windtraps | = Adv. Deathstills |
|---|---|---|---|
| Spice Refinery (Small) | 4.2 mL/s | 2.3 | 0.3 |
| Medium Spice Refinery | 15.6 mL/s | 8.6 | 1.0 |
| Large Spice Refinery | 27.8 mL/s | 15.4 | 1.9 |
The spice water wall: keeping a Large Spice Refinery running continuously drinks
27.8 mL every second — you'd need 15–16 Large Windtraps (2,160 W!) to keep up passively, or
~2 Advanced Deathstills fed a corpse each per hour. Water infrastructure, not spice sand, is usually
the real bottleneck on industrial melange.
Storage
Windtraps only buffer 500 mL internally — without cisterns, production stalls the moment the buffer fills.
| Source | Fill time |
|---|---|
| 1 Windtrap | 34.7 hours |
| 1 Large Windtrap | 15.4 hours |
| Fremen Deathstill | 4 corpses (4 hours) |
| Advanced Fremen Deathstill | 2.2 corpses (~1.9 hours) |