Power Source for Your Watermaker?

[Yachts66]

How do you power your water maker? More importantly, are you happy with what you have? If you had to do it over, how would you do it differently?

Regards,

TJ

[JusDreaming]

I use the engine driven as I figured it was the most dependable source of power. I have a DIY water maker which produces 20 gph so at a fuel consumption rate of 1/2 gph I figure it cost about 1.50 per hour. THat is if I am not going some where and using the engine for propulsion. Basically if the engine is running I am making some water, so no cost incurred

[Beach Cruiser]

We use 12 volt. Lots of solar so no problem running 1 to 2 hours a day which is all we need.

Barry

[mobetah]

A small (7 gallons per hour) homemade 110v AC unit with 1/2hp motor. Runs on shorepower, generator or inverter. we are quite happy with the unit. More info on our homemade watermaker at: S/V MOBETAH: Rebuilding The Watermaker

Bill A.

[Sonosailor]

We could not take power off the engine, which was favoured by the installer, as we have a small catamaran, and the hull sides were too narrow to allow another take-off and belt. Just as well, since with two panels totalling 144 watts and an Air-x Marine wind generator, we often don't need to run the engine for days. Watermaker is an Echo Marine from Chaguaramas.

[svcattales]

I'm currently building a 12 V water maker that should produce 6.5 gal/hr. It's powered by a 1/3 HP motor with a direct coupling to high pressure pump. The motor should draw 27 amps while running so I should be able to run it off my solar panels/wind gen.

It is not as electrically efficient as some of the commercial units, but the installation cost per gallon should be much lower. I estimate the total cost should be about $1,900. The repair and maintenance costs should be much less also since all the parts are readily available and there are no "proprietary parts" that yield big bucks for the commercial units.

I'm about halfway through the installation and will post again when its running.

[Tellie]

Over the past few years I have built both an engine driven unit and a 12v unit for my boat and have learned a lot in the process. I now have a 12v Cape Horn Extreme. Energy is a big factor on my boat as I like to keep my amp usage down. Also one of the reasons I went with the Cape Horn is the redundancy of two smaller feed pumps. If one fails the other will still make water, a handy feature on longer trips were reliability is an issue.

[speciald@ocens.]

As my water maker makes 38g/hr, I can replace used water w/genset while I charge batteries and fridge/freezer - so water is just about free.

[cburger]

I understand running deisel motors with no load can be bad for the motor, I.E. idling to charge batteries, how does this relate to engine powered water makers?

[cburger]

Please excuse my poor spelling

[JusDreaming]

Originally Posted by cburger

I understand running deisel motors with no load can be bad for the motor, I.E. idling to charge batteries, how does this relate to engine powered water makers?

with our unit I built it for the engine running at 2k rpm, so we generally make water while underway

[ka4wja]

TJ,
I have a 12vdc Spectra Ventura MPC-5000......
I have it for over 2.5 years and over 10,000 miles at sea....

Being a 12vdc unit, powered from the house batteries, thru a dedicated breaker, and fed with a short run of 8 ga wire from the breaker, it is batter-powerd, but is "primarily" powered from the sun!!!!

{While, it can, in essence, be powered from the sun (solar charging of batteries), the ocean (water-generator charging of the batteries), diesel fuel (from either the Yanmar or Fischer Panda and battery charger charging the batteries), or from commercial power (when plugged into shore power).....in practicality, it is powered 99% of the time by solar charging of the batteries....}

I like it a LOT.....
It works very well....
It makea about 7 gals / hour (as much as 7.4 gal/hr and as little as 6.8 gal/hr)
It uses about 8 amps at 12vdc....
I have 520 watts of solar panels, with no shading....so I'm energy independent.....and can make as much fresh water as I want....
It fresh water flushes itself every 5 days, whether I'm there or not.....

I wrote an article (w/ lots of photos) about my decision, installation, and operation of my Ventura MPC-5000....
Have a look here:
Watermaker


~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
Here's some additional recent comments I posted regarding watermakers....

My usual advice on watermakers:
1) Decide whether you really need one.....since many that "want" one do not really need one.....it all depends on where and how you're going to be cruising / voyaging.....
2) If you've decided to install a watermaker because you want one, rather than "need" one (as most watermaker owners, myself included, do).....make sure you understand as much or more about them as the guy selling it to you.....since you'll be the one to live with it!!!!
3) Choose a model carefully.......and remember the most important aspect of your decision at this point is the fact that watermakes need to be used (and used often) in order to perform reliably.....


I have a Spectra Ventura MPC-5000, which has worked well for me for the 2.5 years and 10,000 miles+ that I've had it.....
I wrote a detailed article (with lots of photos) about my descision, installation and operation of my Ventura MPC-5000.....
Have a look at it here: Watermaker

The only hick-up was a faulty "salinity probe" which forced me to run the unit for a few minutes with the product water bypassed (manual valve) from the tanks, and then test the product water for purity/salinity manually......until I got a replacement salinity probe....
This took only a coiple of weeks, and didn't adversely impact my making of water.....

~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~

I hope my personal experiences, article, and thoughts here have helped..

Fair winds...

John

[Cheechako]

First I think you need to decide if you will replenish electricity/refrigeration with the engine or wind/solar. Once that is decided you can decide on the water maker. If you are running your engine to create amps, then running the water maker pump will actually be better for the engine loading it up more.
If you are planning on solar/wind charging then 12V is probably best, although if you will move every week or so, or need to catch up on your amps once a week, engine drive might still make sense for the water maker.... The difference is that engine drive units tend to be real quality machinery, 12v units tend to be plastic "toys" in comparison. I dont mean to say they dont work, or not any good...you're just not getting as much bang for your buck when you think about it...

[Tellie]

.... The difference is that engine drive units tend to be real quality machinery, 12v units tend to be plastic "toys" in comparison. I dont mean to say they dont work, or not any good...you're just not getting as much bang for your buck when you think about it...


I agree somewhat with most of your opinions except the part above.
But if you really think about it, when it comes time to repair, rebuild or replace the high pressure systems on a watermaker, Spectras plastic toy Clark pump comes with a life time warranty to the original owner. To second owners of a Spectra pump they offer an exchange program of the Clark pump for far less than the cost of a new quality Cat style pump. Do any of those real machinery pumps have that buck bang?
Like I've said many times before, there is no one watermaker fits all unit. Low voltage, high voltage, solar/wind powered, genset powered, engine take off, hand pump attachment, even (Gawd forbid) a tow behind, a 12gpd to a 5000gpd unit. There are real reasons the choices are so broad. There are lots of questions that have to be answered to find the right watermaker to meet the right needs of a boat owner. What your needs are will not be the needs of the next and vice versa.