On a 7–12 m yacht, every amp-hour matters. Running a high-power watermaker can feel like an indulgence — but staying independent shouldn’t mean running the engine every day. That’s where 12-volt desalination units come into their own. Designed for smaller boats and off-grid adventurers, a system like the LEDI Scout delivers all the water a couple or small crew needs while sipping power quietly from your house bank.
Big watermakers promise big numbers — 40 to 140 litres an hour — but the power draw makes them impractical for modest cruisers. For instance, the Rainman AC system uses a 1.25 kW motor (around 6 A @ 230 V AC), yielding 100–140 L/h — fine for a 50-footer with a generator, but overkill for a solar-powered 9 m yacht. Even DC systems like Spectra are heavy, complex, and costly. High throughput looks impressive on paper, but energy arithmetic tells a different story.
The LEDI Scout is engineered around small-boat realities. It runs directly from your 12-V DC system, drawing around 19 A to produce 20 litres per hour. That’s enough for two to four people living aboard without stressing your batteries. According to The Boat Galley, most cruising couples use about 26 L/day for cooking, drinking, and light washing. Even doubling that for comfort, you’d only run the Scout for two to four hours per day — quietly, on solar.
Let’s do the numbers. Making 50 L with the Scout (≈ 15 L/h) takes about 3 hours × 9 A = 27 Ah. A 200 W solar panel in good sun makes 50 – 80 Ah daily, leaving a healthy margin for refrigeration and lights. A Rainman AC, by contrast, burns 100 Ah in just an hour — the daily output of a 400 W solar array. Efficiency, not brute force, is what makes a system sustainable.
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Unlike many marine RO systems, the Scout arrives as a plug-and-play unit. Inside its 20 kg chassis are an intake strainer, pre-filter, high-pressure pump, RO membrane, and UV steriliser — all pre-wired and tested. Mount it under a settee or in a cockpit locker, plumb the brine discharge to an existing through-hull, connect 12 V power, and you’re making water. Filters and membranes are standard off-the-shelf parts, designed for easy field replacement with no special tools.
For most 7–12 m cruisers, water independence isn’t about filling 600-litre tanks — it’s about replacing what you use each day without engine noise or diesel fumes. A compact 12 V system lets you stay light, quiet, and self-reliant. Whether you’re anchored in the Whitsundays, crossing Cook Strait, or tucked into a remote Pacific atoll, you can turn sunlight and seawater into fresh drinking water.
The ideal cruising setup balances power, comfort, and simplicity. High-output systems may impress dockside, but at sea, efficiency rules. A 12 V watermaker like the LEDI Scout hits that balance — enough water for real living, modest energy use, and parts you can service yourself. For sailors who prefer silence over generators, it’s the practical way to sail further on solar.