Non-Electric Watermaker

[multihullsailor6]

Does anyone have practical experiences with the towed WATERLOG watermaker?

Thanks
Roger

[Therapy]

http://www.cruisersforum.com/forums/...log-12804.html

http://www.cruisersforum.com/forums/...kers-1090.html

http://www.cruisersforum.com/forums/...rs-1090-2.html

http://www.cruisersforum.com/forums/...aker-7603.html

[multihullsailor6]

Is there another water-propelled watermaker being produced other than the Waterlog?

Maybe one where the water-producing equipment itself fixed is on board and only the propellor is lowered into the water.

Roger

[Tellie]

None that I have ever seen or heard of. The inefficiencies of a propeller driven watermaker at this point are too hard to overcome. It still boils down to the ability to create the amount of water pressure and proper flow needed to start salt water reverse osmosis. Secondly, dragging a prop to make water means the boat has to be moving and at enough speed. This eliminates the ability to make water when you are not moving which is a big inconvenience. If your watermaking needs are small you are still better off with a small commercial unit or attempt to build your own from readily available plans on the Internet.

[anotherT34C]

How much pressure is required with common equipment?

I wonder if you can get a decent drip-through rate if you hoist a 5-gallon bag of saltwater to the top of the mast...

[Tellie]

Originally Posted by anotherT34C

How much pressure is required with common equipment?

I wonder if you can get a decent drip-through rate if you hoist a 5-gallon bag of saltwater to the top of the mast...

Usual pressure is around 700-1000psi.

Can't practically be done. If you hoist five gallons of water up your mast and try to route it through a salt water membrane all you'll end up with is five gallons hanging from your mast. Secondly, for easy math purposes, it takes about ten gallons of salt water to produce one gallon of fresh water from the RO process. If you could raise the five gallons high enough, I suspect it would take a Rube Goldberg a few thousand feet of hose and a hot air ballon, you'd still only end up with about 1/2 gal. of fresh water for your efforts.

[dpex]

Has anyone any experience with these devices? They seem like the ideal solution for sail-boats, but they also seem a bit too good to be true.

Any advice would be welcome.

Cheers
Dpex.

[idpnd]

There was a thread somewhere, as they're being sold on UK ebay. The reviews were terrible, apparently it doesn't work at all. I'd make sure I find a credible test of one before I put any cash in..

[anjou]

I came across the website for a uk company making these and they did seem too good to be true.
@£1100 for the unit which can be towed and also hand cranked to give liferaft backup.

Like the old saying goes, If its too good to be true then it usually is.

[Canibul]

in looking into RO systems for our house here, I discovered a couple basic things. A system to process normal crummy swamp water into clean drinking water needs pumps and fittings that can withstand about 250 psi.

The pumps and fittings etc. needed to force the fresh water out of seawater have to operate at 1000 psi. If you look at a device with pumps and tubing and fittings, and it doesn't look like it can handle 1000 psi, constantly, then it won't do the job.

And look at whatever mechanical means is being used to generate that 1000 psi at the pump. If it's an impeller being dragged through the water.....well..it's gonna take a whole lot of gearing to press a drop of seawater through that membrane.

[Tellie]

Water Log water makers do work. You just won't be happy with the results. You have to be moving, no motion no water. Speed is critical, too slow under 7knts or so and it will barely work. Too fast and they skip over the waters surface and will not work at all. Ideal conditions are hard to meet and rarely are those conditions sustained long enough to fill much of your tank. Once you do get it at the right speed you'll be rewarded with very anemic amounts of water. The company claims 24 gallons a day or 1 GPH, again in somewhat perfect conditions. Most unofficial reports I get is more like 1/2gph at best. Just not the GPH numbers you want considering cost, maintenance and aggravation associated with this particular unit. Concept is kewl, but this needs a lot more R&D. The few I have encountered the owners were looking to get rid of them fast. Before considering plunking down the money do a good google search and read what owners of these units have had to say. At this time my opinon would be to put that money towards a better water maker.

[44'cruisingcat]

Originally Posted by dpex

Has anyone any experience with these devices? They seem like the ideal solution for sail-boats, but they also seem a bit too good to be true.

Any advice would be welcome.

Cheers
Dpex.

Doesn't seem ideal to me. You need water when you're at anchor, more so than at sea. A towed water maker isn't going to be much use then.

[dpex]

Originally Posted by Tellie

Water Log water makers do work. You just won't be happy with the results. You have to be moving, no motion no water. Speed is critical, too slow under 7knts or so and it will barely work. Too fast and they skip over the waters surface and will not work at all. Ideal conditions are hard to meet and rarely are those conditions sustained long enough to fill much of your tank. Once you do get it at the right speed you'll be rewarded with very anemic amounts of water. The company claims 24 gallons a day or 1 GPH, again in somewhat perfect conditions. Most unofficial reports I get is more like 1/2gph at best. Just not the GPH numbers you want considering cost, maintenance and aggravation associated with this particular unit. Concept is kewl, but this needs a lot more R&D. The few I have encountered the owners were looking to get rid of them fast. Before considering plunking down the money do a good google search and read what owners of these units have had to say. At this time my opinon would be to put that money towards a better water maker.

Hi,

Thanks for that. Good advice.

My old banger does a sedate 7 knots everywhere. 15Kt breeze? 7 Kts. 50Kt breeze? 7 Kts. I suspect she'd sink faster. But oh! What a sea-boat! She's like one of those epic, large bosomed hospital Matrons, who just shoulders her way through everything and refuses to discuss the matter with any malcontent wave(s). Mind you, she does weigh in at 23,000lbs and Larry Ellison is unlikely to consider her as competition.:--))

But I really do want to free myself from electrical dinguses, and gas. Interior lighting is now all kero; although I do have all the leccy lights, for just in case.

Stove is meth. Anchor-winch hand-draulic. Self steering is Navik. Nav is sextant and paper charts....although I do have a couple of GPS's just in case I lose my sextant. I've been trying to figure out how to run my SSB on coal, but I still haven't solved that one. :--))

You say there are sundry wishing to quit a water-log. Do you have any contacts in that department?

Cheers
Dpex

[dpex]

Woo!

They may be good and reliable, but I simply can't afford NZ$10K for one of these.

Anyone got any top suggestions for a slightly (read hugely) less expensive alternative?

I've been wondering about the concept of using a solar panel (the water heating variety) attached to a cooling coil. Hmmm. Could be just s sweet dream.

But $10K is way beyond my budget, so any help on the matter would be greatly appreciated.

Cheers
Dpex.

[Tellie]

Originally Posted by dpex

Woo!

They may be good and reliable, but I simply can't afford NZ$10K for one of these.

Anyone got any top suggestions for a slightly (read hugely) less expensive alternative?

I've been wondering about the concept of using a solar panel (the water heating variety) attached to a cooling coil. Hmmm. Could be just s sweet dream.

But $10K is way beyond my budget, so any help on the matter would be greatly appreciated.

Cheers
Dpex.

Unfortunatly no water maker worth having on a cruising boat is going to be cheap. My currency converter "If Accurate" says 10,000NZ is 7,425 US. You can easily take off a few thousand of that for a good basic watermaker that will really meet your needs. Even on a Spectra. There's always the build it yourself alternative with plans available. The condensation approach to making water on a boat has been mulled around for years. Not to discourage great inventiveness, but they have a bit more proven track record than the ingenoius but doomed to disappoint idea you proposed.