What is the best 12 V DC watermaker for small boats?

LEDI Scout SW20 leads this shortlist at 10.0 watt-hours per litre: 1.5 hours and 300 Wh to make 30 litres. "Best" here means best on the numbers for this combination — the ordering is by what small boats optimise for, and it does not account for what your dealer can actually service.

How much 12 V DC power does a watermaker need on small boats?

For 30 litres a day, the leader here draws about 300 watt-hours, or roughly 25 amp-hours from a 12 V bank. The spread across this shortlist is wide: compare the Wh/L column rather than the wattage, because a thirstier system that runs for less time can still cost more energy overall.

Why are only 7 systems listed?

Because two filters are applied, not one. 8 systems in our table suit small boats on output and configuration; 7 of those run on 12 V DC. The remaining 1 are on the full small boats shortlist and are worth a look if your electrical setup is not fixed.

12 V DC · small boats

12 V DC watermakers for small boats.

Two constraints at once: small boats typically need about 30 litres a day, and a 12 V DC system has to make them inside what that electrical setup can deliver. These are the 7 systems that satisfy both.

Systems that fit both7of 8 that suit small boats

Daily need30 L2 aboard at 15 L each

Leader hereLEDI Scout SW201.5 h and 300 Wh for 30 L

Why 12 V DC. Runs straight off a 12 V house bank with no inverter and no generator. Output is modest by design, so the question is whether your daily litres fit inside a sensible run time. On small boats: A modest house bank and a small array rule out the kilowatt-class systems entirely. This is 12 V territory, and it is where the low-output energy-recovery units shine.

12 V DC systems for small boats

Ordered by what small boats optimise for. Run time and energy below are for 30 litres a day.

System	Power	Output L/hr	Draw W	Wh per litre	Price
Scout SW20 LEDIreported	12V DC	20	200	10.0	on request
Portable 12VDC 34L Rainman	12V DC	26–37	400	12.7	$4,898
Zen 30 Schenker	12/24V DC	30	110	3.7	$6,300
Ventura 150 Deluxe Spectra	12/24V DC	24	108	4.5	$6,000
Ventura 150 Connect Spectra	12/24V DC	24	108	4.5	$7,400
Modular 12VDC 34L Rainman	12V DC	26–37	400	12.7	$5,053
Ventura 200 Tropical Spectra · spec unconfirmed	12/24V DC	31	—	not published	$8,200

Under 6 Wh/L · energy recovery

6–12 Wh/L

Over 12 Wh/L

1 further system suits small boats but does not run on 12 V DC — see the full shortlist.

Check it against your own bank

30 litres a day is a planning figure. Put in your crew, your battery bank and your real solar surplus and see which of these still fit.

Open the calculator

Common questions

What is the best 12 V DC watermaker for small boats?: LEDI Scout SW20 leads this shortlist at 10.0 watt-hours per litre: 1.5 hours and 300 Wh to make 30 litres. "Best" here means best on the numbers for this combination — the ordering is by what small boats optimise for, and it does not account for what your dealer can actually service.
How much 12 V DC power does a watermaker need on small boats?: For 30 litres a day, the leader here draws about 300 watt-hours, or roughly 25 amp-hours from a 12 V bank. The spread across this shortlist is wide: compare the Wh/L column rather than the wattage, because a thirstier system that runs for less time can still cost more energy overall.
Why are only 7 systems listed?: Because two filters are applied, not one. 8 systems in our table suit small boats on output and configuration; 7 of those run on 12 V DC. The remaining 1 are on the full small boats shortlist and are worth a look if your electrical setup is not fixed.

Same boat, other power

Change one constraint

Everything for small boats →

24 V DC for small boats4 All 12 V DC systems Other boat types

How this shortlist is built. 30 litres a day is 2 aboard at 15 litres each — a planning figure for this kind of boat, not a measurement of yours. From the systems that suit small boats, this page keeps only those the manufacturer rates for 12 V DC. Watt-hours per litre is rated draw divided by rated output. Methodology.