A 12V watermaker for a sailboat is the most practical way to become genuinely water-independent offshore. Rather than rationing tanks, chasing marinas, or hauling jerry cans, you run a compact reverse-osmosis unit off your existing house battery bank and produce clean drinking water from seawater or brackish water whenever you need it. This guide walks through how to choose the right system for your boat, your crew, and your power setup, without the marketing fluff.
Why 12V Makes Sense on a Sailboat
Most sailboats already carry a 12V DC system for navigation electronics, lighting, and an autopilot. A 12V watermaker plugs directly into that infrastructure. There is no generator to run, no 240V inverter to size, and no extra fuel to carry. With 200 to 400 watts of solar on deck and a reasonable house battery bank, most sailors can run a 12V watermaker comfortably alongside their other loads.
That simplicity is the main reason 12V systems have become the standard choice for cruising yachts in the 6 to 15 metre range. They suit the power budgets these boats actually have, and they are far easier to manage on passage than AC-powered alternatives.
What Output Do You Actually Need?
Before choosing a unit, work out your daily water budget. Drinking, cooking, and basic hygiene for two people typically requires 4 to 8 litres per person per day at sea. Add in washing up and occasional freshwater rinses and you might land at 15 to 25 litres per day for a couple.
A 10 LPH (litres per hour) watermaker running for two hours a day covers that comfortably. Step up to a 20 LPH unit and you can fill that budget in under an hour, leaving more time and battery capacity for other loads. Bigger crews, longer passages, or boats with showers underway will need more output.
A useful rule of thumb: size for your realistic daily use, not your peak demand. It is better to run your watermaker for a consistent hour each day than to run a larger unit occasionally and let it sit idle.
For more on sizing, see How Much Water Does a Watermaker Produce? and How Much Water Do You Actually Need?
The LEDI Scout: A 12V Watermaker Built for Sailboats
The LEDI Scout is designed specifically for the kind of sailing most Australians do: coastal passages, island hopping, extended cruising on yachts from 20 to 50 feet, and occasional offshore work. It is available in 10 LPH and 20 LPH output ratings, both running on 12V DC at 16 to 18 amps.
The Scout weighs 18 kg and is designed for single-person carry. There is no installation required. You drop the stainless steel intake over the side, connect the supplied hoses, and you are making water within minutes. That matters on a sailboat where lockers are full and below-deck space is at a premium.
Key specifications worth knowing:
- Output: 10 LPH or 20 LPH
- Power draw: 16 to 18A at 12V DC
- Salt rejection: 99.4% (typical output 250 to 300 ppm TDS, under 800 ppm)
- Built-in UV steriliser, meets Australian drinking-water standards
- Handles seawater up to 35,000 ppm and brackish or river water
- High-pressure pump: Pumptec 107SS (USA-made, 316 stainless, around 800 PSI)
- 5-micron pre-filter included
- Weight: 18 kg, single-person carry
- Price: from $4,799 AUD
The Scout is made on the Gold Coast, not imported, which means no overseas distributor markup and no freight on an 18 kg case. It uses the same commercial marine-grade parts found in fixed installed watermakers that often cost $10,000 to $25,000 installed, but because LEDI builds and services them directly, the price is significantly lower.
Power and Solar: What You Need to Know
At 16 to 18A draw, the Scout uses roughly 200 to 220 watt-hours per hour of operation. A standard 12V house battery bank with 200 to 400 watts of solar handles this comfortably as part of a normal day's electrical load. No generator is needed.
If your boat is already solar-equipped for navigation and lighting, the Scout fits into that system without forcing an upgrade. On longer passages with limited sun, you can time your watermaking sessions around peak solar production or draw from a charged battery bank during the day.
For a detailed look at how 12V systems work in practice, see 12V Watermakers for Small Yachts: Practical Water Independence at Sea.
Portable vs Installed: Which Makes More Sense?
A portable unit like the Scout stows in a locker when not in use, doubles as a backup to a fixed system, and can be used on a different boat or taken camping. It does not require a professional installation, hose penetrations through the hull, or a dedicated compartment. For most sailors without a full-time liveaboard setup, this is the more practical choice.
An installed or modular system makes more sense if you want the watermaker permanently plumbed in, feeding directly to your tanks, with a remote control panel and autoflush. LEDI's Modular kit is designed for exactly that, configured for below-deck installation in refits and new builds. Pricing depends on configuration.
For bigger crews, liveaboards, or boats that need 40 to 80 LPH output, the LEDI Nomad is the next step up. Available in 12V, 24V, and 48V, it includes an integrated control panel, two-stage pre-filter, and TDS and flow monitoring. The Nomad is available from $8,299 AUD, with final pricing on higher output configurations being finalised. If you are interested, contact the LEDI team to register your interest.
See Portable vs Installed Watermaker for a full comparison of the two approaches.
Maintenance: What It Actually Takes
Honest answer: a 12V RO watermaker needs some basic upkeep, but nothing complicated. The three main tasks are:
- Pre-filter changes: The 5-micron pre-filter cartridge needs replacing periodically depending on water turbidity. Costs $25 AUD. Takes five minutes.
- Freshwater flushing: If the unit is not going to be used for more than a few days, flush it with fresh water to prevent biological growth in the membrane. This is quick and uses very little water.
- Membrane pickling: For longer storage, the membrane needs to be pickled with a preservation solution. LEDI stocks maintenance chemicals for this.
Every wear part on the Scout is field-replaceable, and LEDI posts spare parts Australia-wide and internationally, usually within one business day. The spares range includes membranes, pre-filters, valves, and service kits. The RO membrane itself costs $300 AUD and is covered by a pro-rata warranty.
Warranty and After-Sales Support
The Scout comes with a 1-year warranty, extended to 2 years when you register the unit. LEDI offers lifetime in-house servicing from the Gold Coast. When you contact LEDI, you speak to a real person, not a call centre. That matters when you are mid-passage and have a question that needs a straight answer fast.
Contact the team at info@ledi.com.au or on +61 494 562 668.
The Bottom Line
A 12V watermaker for a sailboat does not need to be complicated or expensive. The LEDI Scout is a practical, well-built, Australian-made unit that gets you water-independent without a professional installation, a generator, or a five-figure spend. It suits trailer sailers, coastal cruisers, catamarans, and offshore passage-makers equally well.
If you are ready to stop rationing your tanks, the Scout is the most straightforward starting point. View the LEDI Scout or get in touch with the team if you want to talk through which output rating suits your setup.
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