Offshore Hydrogen Plant

I had previously proposed wind-based recycling plants. They utilized the wind's kinetic energy to recycle landfills using mechanical means. This idea can be further enhanced to produce hydrogen and oxygen from seawater. The setup would be composed of two vertical offshore wind turbines working in tandem. The first one would be purely mechanical and the other would be a classical wind turbine generating electricity. Tt would be designed to generate DC instead of AC.

The objective is to vaporize seawater using a vacuum. The shaft of the mechanical vertical wind turbine would drive a vacuum pump just below the sea level. The vacuum pump would be surrounded by capillary aluminum pipes which carry seawater in them. The pipes would have their bottom ends open to allow seawater to enter. The top ends of the pipes would be vacuumed to vaporize the water, which would then be electrolyzed by the DC supplied by the neighboring vertical wind turbine.

The capillary pipes would warm the seawater in them using the heat generated by the vacuum pump. As a result, the efficiency losses of the pump would be partially recovered by the seawater, and the pump would be kept cooler. The capillary pipes would thin the water into a meniscus at the tube edge. This reduces surface tension, and the vacuum pressure lowers the energy needed for boiling. As a result, the heat recovered from the pump is enough to boil the water.

At the exit of the vacuum pump, the water vapor would be electrolyzed using a Direct-DC feed. High vapor temperature reduces the electrical Gibbs free energy requirement. Direct-DC eliminates ac/dc conversion losses (typically 3-5 percent).

The vertical wind turbines can be installed in close proximity, further improving their efficiency. This would create an island-based hydrogen production plant. The combined production output would then be sent to the coast using underwater pipes. On land, the hydrogen would be pumped into the country-wide hydrogen pipeline. The oxygen would be stored and sent to demanding chemical plants.

5MW Turbine Calculation (Estimated Yield)

Assumed Turbine Output: 5,000,000 Watts

Assumed System Efficiency (Combined): 75 percent

Effective Power for Electrolysis: 3,750,000 Watts

Energy required per kg of H₂ (Vapor phase): ≈ 45 kWh/kg

Calculation: 3,750 kW / 45 kWh per kg

Estimated Yield: 83.3 kg of Hydrogen per hour

Oxygen Byproduct: ≈ 666.4 kg per hour (8:1 mass ratio)