Crew Demand • Potable Storage • RO Product Capacity • Recovery • Feed & Brine • N-1 Redundancy • TDS Screen • Energy • Voyage Reserve

Ship Freshwater & RO Capacity Tool

Turn people, service loads, potable-water storage and watermaker capacity into a voyage freshwater plan. Simple mode answers daily demand, RO coverage, reserve endurance and bunker-water requirement. Advanced builds the ship from consumer groups, service loads, potable tanks, RO units and voyage legs, then checks N-1 production, feed/brine flow, product-TDS screening, energy and tank inventory across the voyage.

Figures represent
Need N-1 watermakers, tank-by-tank inventory, feed/brine and voyage legs? Click Advanced above.Demand defaults are examples only. MLC requires adequate drinking water, while quantity and quality details are implemented by flag State/company requirements.
DemandPeople + service water
ProductionRO output vs daily use
ReserveTank endurance & makeup

Freshwater Demand & Voyage

L/person/day, user-entered planning basis.
m³/day for galley, laundry, cleaning or technical loads not included above.
days.
days of current daily demand.

Storage & RO Production

m³.
m³.
m³/day.
% of rated output across the voyage.
m³ available during the voyage.

Reserve / Product-Water Basis

days of baseline demand.
mg/L. TDS alone does not prove potability.
% of baseline daily demand.

People / Hotel Demand Register

UseGroupPeopleL/person/dayDuty %

Fixed Freshwater Load Register

UseLoadm³/dayDuty %

Potable / Freshwater Tank Register

Usable fraction lets you keep unpumpable volume or operating restrictions outside the planning inventory.

UseAvailable?Capacity m³Current fill %Usable %

RO Watermaker Register

Modeled product TDS = feed TDS × (1 − salt rejection). Actual product-divert logic and potable-water acceptance require the vessel’s salinity/conductivity and water-quality controls.

UseAvailable?Rated product m³/dayCapacity factor %Recovery %Salt rejection %Feed TDS mg/LSEC kWh/m³

Voyage Leg Register

Legs are simulated in the entered order. Demand factor applies to baseline consumption; RO operating factor represents sea/port restrictions, maintenance or planned run time. Shore uplift is added at the start of that leg, subject to usable tank capacity.

UsePhaseDaysDemand factor %RO operation %Shore uplift m³

Freshwater / Watermaker Checks

Water-quality boundary: capacity is not potability. WHO ship-sanitation guidance treats onboard-produced water as part of a complete water-safety system and notes the need for appropriate desalination, stabilization/remineralization and disinfection controls. This tool does not certify microbiological, chemical or health compliance.
By the ShipUniverse Editorial Team — About Us | Contact