Old oil platforms in the Gulf of Mexico can make the fuel the world's ships
will burn next decade. Some plans make a lot of money. Some lose it all.
This whole page is a calculator — move any number, check our homework.
Wind is free. Seawater is free. The hard part is the money —
and every plan below says exactly how much it needs and what it pays back.
Green means a good deal. Yellow means risky. Red means walk away.
These are estimates from public studies — not promises, not investment advice.
The idea, in one picture
Ships burn dirty fuel today because clean fuel costs too much to make.
We make it where the wind blows hardest — offshore — and sell it where ships already stop.
Every arrow is a step a real plant already does. The only question is whether the money works — that is what the rest of this page checks.
Why offshore?
The wind is stronger and steadier at sea — roughly twice as productive as on land. And about 1,500 old Gulf platforms are looking for a second job instead of being scrapped.
Why now?
Ships must cut pollution. New global rules are forcing the biggest ships to switch fuels this decade. Somebody has to sell them the new fuel. We would rather it be us.
Why us?
Every one of these plants needs pumps — for seawater, for fuel, for pressure. Pumps are our family's trade for 20+ years. We start by selling the pumps, then earn our seat at the bigger table.
The money: three ways to play
Same technology, three different-sized bets. Each one says how much cash it needs and what it pays back. Pick your appetite.
DOOR 1 · SAFEST · START HERE
Sell the pumps
$3M to raise
Build a new pump line for clean-fuel plants: seawater pumps, fuel pumps, pressure pumps
Each pump package sells for $200k–$400k
Sell about 10 and the raise is paid back
After that, profit on every unit — and customers arrive as the industry builds out
LOW RISK · STEADY BUSINESS
DOOR 2 · LOW COST · FAST
Sell into big projects
~$0 to raise
Big energy companies are already building clean-fuel plants — they need equipment
They spend their $100M+. We supply the pump packages and collect the margin
Our name ends up on real projects without our money
Also the best market research possible: we learn what buyers actually want
LOW RISK · ZERO CAPITAL
DOOR 3 · THE BIG ONE · LATER
Own a slice of a plant
$135M total · we raise $30–50M as our share, banks & partners cover the rest
Rebuild one old Gulf platform: wind power + a fuel plant on top
The calculator's best version pays back in ~5 years, then earns about 18% per year — after upkeep, a mid-life stack swap, and end-of-life cleanup
With mini-nuclear added later: ~30% per year, money back in ~3 years
Only after a fuel buyer signs a long-term contract. Never on hope
HIGH RISK · HIGH REWARD · PHASE 3
This loop is Door 3's best version (old Gulf rig + wind, from the calculator below). The calculator shows the weaker versions too — honestly.
The calculator
Eight ready-made stories below. Click one. Every slider changes the deal —
the verdict, the money needed, and the payback update instantly.
GREEN = good deal · YELLOW = only with a signed buyer · RED = walk away · chips assume the US Gulf site — flip the Location switch in the Plant panel to re-price any story
The Plant
small500 MW
$5M$200M
$5M$300M
$400$2,000/kW
5%16%
1030 yrs
1%8%
$0 (they last forever?)$80M
walk away free$60M
Offshore machines wear out. The stacks get swapped around year 10, the rig has to be cleaned up at the end, and yearly upkeep (3% ≈ $4M/yr on this plan) rides on top of both. All three are counted in every number on this page.
Power Source mix adds to 100%
Wind blows % of the time
Wind power cost $/MWh
Sun shines % of the time
Solar power cost $/MWh
Tides run % of the time
Tidal power cost $/MWh
Runs % of the time
Always-on cost $/MWh
Shared Steps
4660 kWh/kg
The hydrogen is then squeezed into tanks. Squeezing to 700 bar ≈ 3 kWh per kg. Liquefying it ≈ 12 kWh per kg. Set the slider below to match.
015 kWh/kg
sell hydrogen rawall into fuel
Filtering seawater costs almost nothing (0.035 kWh per kg). It is never the problem. Electricity is the problem.
Making Ammonia
0.41.6 MWh/t
Air is free — ammonia grabs nitrogen from the air. That's why it is the only fuel on this page with no carbon problem.
Making Methanol
0.42.0 MWh/t
Methanol needs carbon dioxide (CO₂). Ships already burn methanol today — it is the easiest fuel to adopt.
Making Diesel & Jet Fuel
1.03.0 MWh/t
This fuel works in today's engines and planes — so it sells at premium prices. But it needs about 3 tonnes of CO₂ per tonne of fuel. Carbon is the whole ballgame here.
Making Clean Natural Gas
0.21.5 MWh/t
This fuel can flow through today's gas pipelines and ships. The catch: it competes with cheap natural gas, so it needs a premium buyer (Japan, Korea).
Where The CO₂ Comes From decides everything for carbon fuels
$50$400/t
0.83.5 MWh/t
$10M$200M
By boat is how real plants run today. Sucking CO₂ from air works but drinks power. From seawater is still lab science — treat it as research, not business.
Prices
$300$2,000/t
$300$2,000/t
$500$5,000/t
$300$4,000/t
$1$15/kg
sell at the platform$150/t
$0$3/kg H2
vent it (default)$0.60/kg H₂
Every kg of hydrogen comes with 8 kg of pure oxygen. Most plans vent it. If a buyer exists — fish farms and steel mills both buy oxygen — a realistic credit is $0.05–0.20/kg of H₂. There are no rare-earth byproducts: seawater has none, and electrolysis extracts nothing from it (Fritz Haber went bankrupt chasing gold in seawater — parts per trillion).
$20$300/MWh
$0$1/kg
What the fuel sells for
Cost to make 1 kg of hydrogen
Ammonia cost
levelized, $/t NH₃
Hydrogen made per day
Ammonia output
tonnes / day
Total money needed
Yearly profit (after running costs)
Simple payback
years to get your money back
Return rate (IRR)
per year, over the project life
Total profit over project life
Blended power
how often it runs · power cost
Yearly sales
Yearly costs
The three prices, side by side
SELL PRICE
COST TO MAKE
STORE & PRESSURE
LOAD & SHIP
PROFIT PER UNIT
HYDROGEN (raw gas)
at platform
AMMONIA (fuel)
Store, pressure AND load-and-ship are already counted inside “cost to make” — each gets its own column because buyers, banks, and engineers ask for them separately.
Which site wins, fuel by fuel — at your settings
Same plant and sliders, only the site changes — the computer quietly runs all 20 fuel-and-site combinations and shows each fuel's winner. The highlighted row is the fuel you're viewing.
Where each kilogram's cost goes
Electricity is almost always the biggest slice. That is why the power source sliders matter more than everything else combined.
The price ruler — cost per kilogram (cheaper is better)
Ships pay about $1.80/kg for regular fuel today (marked on the ruler as parity). Above roughly $9, a clean-fuel plant struggles to sell anything without government help.
How many big ships does this feed?
What if things change?
The dial that hurts most is almost always power — its cost and how often it blows.
The physical footprint
How the plant works — follow the pipes
Seawater in one end, ship fuel out the other. Every number on this diagram is live —
it changes when you move the calculator sliders above.
Filtering water is almost free. Splitting water is the whole business. Carbon is a delivery problem. Steady power is everything.
Where the ships fill up
Ships don't stop in the middle of the ocean. They fill up at a few big ports, then run.
A fuel plant only makes money sitting next to one of these. The calculator's Location switch
prices five of these sites — each note under it says what that site gives you and what it costs you.
Port
Fuel sold in 2025
Why it matters to us
Singapore
56.8 Mt
A quarter of all ship fuel on Earth. Ammonia barge arrives 2027.
Rotterdam / Antwerp
9.8 + 7.9 Mt
Europe's green-fuel rules already have teeth. Clean fuel sells here first.
Zhoushan, China
8.0 Mt
China's state-backed clean-fuel hub.
Fujairah, UAE
~7.4M m³
The price marker for the East.
Busan, Korea
~6 Mt class
Ammonia ships and clean-gas buyers.
Houston / US Gulf
US Gulf hub
Home. Where the old platforms are, where we work, where the first plant should be.
Panama / Gibraltar
~5 / ~4.6 Mt
Chokepoint stops — ships pay extra when routes are stressed.
The ocean cluster — neighbors who pay each other
One mooring can hold more than one business. The fuel plant is the anchor;
a fish farm and a data center make it stronger — the fish breathe our oxygen, the data center warms their water,
and everyone shares one fiber line, one crew boat, and one permit.
1 · Your fuel plant
The anchor tenant. Wind and seawater become ship fuel — the business the rest of this page is about. Everything else plugs into its platform, crew, and cable.
2 · The fish farm
Buys your oxygen. Every kg of hydrogen makes 8 kg of pure O₂ — fish farms inject it so packed pens don't suffocate. Warm water from the data center grows the fish faster, year-round. Two costs become two incomes.
3 · The data center
Buys spare power. It runs training jobs when the wind blows and pauses in the lulls — the one kind of computing that fits a wind platform. Its cooling water leaves warm; the fish farm pipes it straight into the pens.
Honest fine print: the data center only works with firm power or flexible AI jobs — 24/7 uptime on wind alone doesn't pencil (ask Microsoft's Natick project). And none of this works mid-ocean: the cluster lives next to a real port. Same map rule as always.
THE MAP RULE — If a ship wouldn't already pass within a few hours of the platform, the platform isn't a gas station. It's a very expensive view.
Proof this is real
None of this is science fiction. It's already running — just not yet at full scale in the Gulf.
North Sea, July 2026
An old gas platform off the Netherlands made its first clean hydrogen straight from seawater, powered by wind. The small-scale version of our idea already works.
A giant fuel ship, being built
A 268-meter ship is being fitted with 300 MW of hydrogen machines and an ammonia plant on deck — about 300,000 tonnes of clean ammonia a year. Our "big plan" at industry scale.
Clean methanol, running since 2024
A plant in Denmark makes clean methanol at commercial scale — electricity + captured carbon. It works on land; our calculator shows why the sea version is harder.
We also show the failures, honestly: one European country paused offshore hydrogen demos for five years because buyers showed up slower than the hype. And a city's hydrogen buses — bought for £556k each — resold for £30k when the fuel stations broke. That is what happens when a plan ignores the money. This page never ignores the money.
The plan: start small, dream big
1
Start tiny — sell pumps
Build the Mariner pump line: seawater pumps, fuel pumps, pressure pumps for clean-fuel plants. Prove the market, get paid while we learn.
RAISE $2–3.5M · 12–18 MONTHS · LOW RISK
2
Sell into someone else's plant
Big energy companies are spending billions on clean-fuel plants. They need equipment. They spend their money; we supply the packages and take the margin — and learn exactly what buyers want.
RAISE ~$0 · 12–36 MONTHS · LOW RISK
3
Own a slice of one plant
Rebuild one old Gulf platform with wind power and a fuel plant on top — only after a fuel buyer signs a long-term contract. Raise $30–50M as our share of ~$135M. The best version pays ~18%/yr, money back in ~5 years, even after the mid-life stack swap and cleanup are paid for.