Desalination System Cost Calculator

Calculate watermaker costs by vessel size and water demand. Compare reverse osmosis systems, estimate energy consumption, and plan maintenance budgets.

Watermaker Sizing & Cost

Find the right watermaker size based on vessel capacity and daily water needs.

Total Persons (Guests + Crew)

Water Usage Level

Brand Tier

Additional Features

Energy Cost Calculator

Calculate the ongoing energy cost of running your watermaker system.

System Capacity (GPH)

Daily Run Hours

System Efficiency

Generator Fuel Cost ($/kWh)

Maintenance & Lifecycle Cost

Plan membrane replacement, servicing, and long-term costs.

System Purchase Price

Number of Membranes

Annual Running Hours

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How We Calculate Desalination Costs

Daily Water Need = Persons × Gallons Per Person Per Day
Required GPH = Daily Need ÷ Daily Run Hours × 1.25 safety margin
Energy Cost = (GPH × Hours × kWh per 100 gal ÷ 100) × Fuel Cost per kWh
Annual Maintenance = System Cost × 0.05-0.08 + Membrane Replacement Reserve

Frequently Asked Questions

How much does a yacht watermaker cost?

Yacht watermakers cost $5,000-$12,000 for small 20-40 GPH units, $15,000-$40,000 for mid-range 60-150 GPH units, and $50,000-$200,000+ for high-capacity 200-1,000+ GPH superyacht systems. Installation adds 25-40%.

How much water does a yacht need per day?

Average consumption is 50-80 gallons per person per day on luxury yachts. A 100-foot yacht with 12 persons needs 600-960 gallons daily. Superyachts with pools may need 2,000-5,000+ gallons per day.

How long does a yacht watermaker last?

Quality watermakers last 10-20 years. Membranes need replacement every 3-7 years ($1,000-$5,000 each). High-pressure pumps may need rebuilding every 5-8 years. Annual maintenance runs $2,000-$8,000.

What is the best watermaker brand for yachts?

Leading brands include Sea Recovery for superyachts, Spectra for energy-efficient sailing yachts, Village Marine for commercial applications, and HRO for compact systems.

How much power does a yacht watermaker use?

Standard systems use 5-8 kWh per 100 gallons. Energy-recovery systems use 3-5 kWh. Spectra's low-pressure systems use as little as 1-2 kWh per 100 gallons.

Understanding Yacht Desalination Systems

Desalination systems, commonly called watermakers, have become essential equipment on cruising and charter yachts. These reverse osmosis systems convert seawater into potable freshwater, providing independence from shore-based water supplies and eliminating the need to carry large water tanks. For superyachts with crews of 10-20 and guest expectations of unlimited hot water, multiple showers, laundry services, and even swimming pools, reliable high-capacity watermaking is not optional but essential infrastructure.

Reverse Osmosis Technology

Marine watermakers use high-pressure pumps to force seawater through semi-permeable membranes that remove 99.5%+ of dissolved salts. The process requires significant energy, making generator capacity an important consideration. Modern energy-recovery systems recapture pressure from the waste brine stream, reducing power consumption by 40-60%. Low-pressure systems like those from Spectra use a different approach, operating at lower pressures with longer run times but dramatically reduced energy consumption, making them ideal for sailing yachts relying on battery or solar power.

Installation and Space Requirements

Watermaker installation requires careful planning for seawater intake positioning, pre-filtration systems, membrane housing, high-pressure pumping, product water storage, and brine discharge. Systems must be located below the waterline for reliable intake. Pre-filters remove sediment and biological matter to protect membranes. Product water should pass through UV sterilization and optional mineralization before reaching taps. The complete installation typically occupies 10-30 square feet of engine room space depending on capacity.

Maintenance Best Practices

Proper maintenance is critical for watermaker longevity and water quality. Membranes must be flushed with freshwater after each use to prevent salt crystallization. Chemical cleaning every 3-6 months removes biological fouling. Pre-filters require regular replacement. Water quality should be tested regularly with TDS meters. When not in use for extended periods, membranes must be pickled with preservative solution to prevent biological growth. Neglecting maintenance can reduce membrane life from 5-7 years to less than 2 years, making proper care a significant cost-saving measure.