12 volt watermakers, which one?

[newhaul]

Originally Posted by Franziska

@Pete7

Thanks, we drink the tap water all the time for now. But, we are prepping slowly for the big departure to places where this will not be possible.

Apart from that we try to avoid marinas where we can. Anchor and mooring is, much more our thing.
Thats including choosing equipment and deciding budget wise where we set our preferences.

Will not purchase before final refit though.
Funny enough I spent a lot of time on the channel islands 2016...

one bit of advice is not to get the powersurvivor40 ( I have the 35) like I run . For 2 people it is marginal and there are better units output wise available in the price range.

[a64pilot]

Seeing as you already have a genny and I assume plan on keeping one, I’d say go for an AC Watermaker, that makes more sense than spending big $$$ for an energy recovery DC one, and then using the genny to charge the batteries.
Once you buy into having a generator, what kind of Watermaker decision is easy, I think.
Even if the generator breaks, I can still make water using my high output alternator and inverter.

[44'cruisingcat]

Originally Posted by a64pilot

There is nothing wrong with my Solar, I get over 300 AH per good day from it, but it’s not nearly that simple, it more than anything is the number of hours to fully recharge a bank exceed the number of Solar hours there are in a day, plus the closer you get to fully charged, the less efficient charging a lead acid bank becomes, above 90% or so charged, its way down only about 50% efficient, but mostly its the number of Solar hours there are in a day.

So let’s talk a little about average AC powered 30 GPH watermaker pulls about 1100 to 1200 W to make water. However it swaps efficiency for simplicity and cost, 1200 W is roughly a little more than 100 amps from a battery bank, don’t forget Peukert’s law. So you get less than 30gls of water for your 100 AH, less cause there is start up and a fresh water flush, so say 25 gls of water or 4 AH per gl.

I believe a Spectra will make water at the rate of 1 AH per gallon. That’s what they cost so darn much, cause they are worth it

So I’m not saying you can’t run a DC Watermaker off of your battery bank, just that you can’t run the average AC Watermaker off of your battery bank whether you put a DC motor on it or not.

Now there are of course DC water makers out there, and of course they do work, but likely it makes the best sense to run them when your motoring ,unless of course they are as efficient as a Spectra is.

I am not bad mouthing AC watermakers, I have one, just I accept that they are enormously inefficient compared to a Spectra, but that’s OK with me, cause my generator has power to spare.

But when your charge controller starts cutting back on the amps going to your batteries, that's the ideal time to run a 12v watermaker! You're putting "wasted" solar capacity to good use!

A Spectra makes about 4 litres per amp hour, our Little wonder makes a bit more than 2. So it's really not bad, and can certainly be run off our solar.

[Tellie]

Originally Posted by sy_gilana

I have never understood the watts per gallon metric. In my opinion its not a measure of anything. Please correct me if I am wrong.

A watt is a measure of power, that is, instantaneous power, analogous to speed.
Watts per gallon, umm thats like saying I can do 100mph on a gallon.

What is more important is the energy consumption per gallon.

So if the machine can do say 10 gallons per hour and it draws 15 watts per gallon, do you multiply that and say its 150 watts per hour, at 12 v it would be 12.5 Ah per Gallon.

Is that correct ?

15 Watts is 1.25 Amperes, is it conceivable that is true? Thats less than a nav light.

I would love someone who has a "15watt per gallon" machine to actually measure the amperage while it is in production.

Spectras Cape Horn Extreme is 16Watts per gallon. Be careful on some of the above claims.

[Tellie]

Originally Posted by SV THIRD DAY

So which way is the "right way"....easy....whatever works for YOU. And there is the danger of advice.....unless you know the mindset and what makes sense to you and the person giving you advice...well that is how people wind up with the "wrong water maker".

My turn, BINGO!


Give me ten identical boats and I'll show you ten entirely different watermaker needs. I see this all the time with those that want to save their hard earned dollars going for price first instead of what their needs AND their boats capabilities are just to waste a ton of money and be unhappy with their purchase.



PS I don't knock other watermaker companies, but if you think you are getting quality watermaker for $1,600 go for it. I just don't know the right words to put together that would matter.

[newhaul]

Originally Posted by sy_gilana

.

What is more important is the energy consumption per gallon.

So if the machine can do say 10 gallons per hour and it draws 15 watts per gallon, do you multiply that and say its 150 watts per hour, at 12 v it would be 12.5 Ah per Gallon.

Is that correct ?
.

I just noticed you have the decimal in the wrong spot in your example.
It should read 1.25 ah per gallon. Not 12.5ah per gallon.

[Tellie]

Originally Posted by newhaul

one bit of advice is not to get the powersurvivor40 ( I have the 35) like I run . For 2 people it is marginal and there are better units output wise available in the price range.

AGREED, and I sell them (rarely). It would be a rare case where someone started out wanting a Power Survivor of any size that I don't walk them right into at the least a Ventura 150. A slight bit more in cost up front but a far superior watermaker for todays needs.

[newhaul]

Originally Posted by Tellie

My turn, BINGO!


Give me ten identical boats and I'll show you ten entirely different watermaker needs. I see this all the time with those that want to save their hard earned dollars going for price first instead of what their needs AND their boats capabilities are just to waste a ton of money and be unhappy with their purchase.



PS I don't knock other watermaker companies, but if you think you are getting quality watermaker for $1,600 go for it. I just don't know the right words to put together that would matter.

I didn't knock katadyn for their watermaker. I just stated that the 35/40 would likely not produce enough to make many boat owners happy.
( side note are my membranes any cheaper since the merger?)

[newhaul]

Originally Posted by Tellie

AGREED, and I sell them (rarely). It would be a rare case where someone started out wanting a Power Survivor of any size that I don't walk them right into at the least a Ventura 150. A slight bit more in cost up front but a far superior watermaker for todays needs.

I got mine for 200 so it was kind of a no brainer. I will live with the production limits.

[Franziska]

One thing though, I would think there are also cultural differences in water usage between US and Europe.

This is not meant as criticism but water usage on US boats is very likely higher, because people are more used to it.
I'd think the average European boat might well get along with slightly smaller desalinators than the average US boat.

Just as Europeans tend to be more often happy without an air conditioning.

Just a thought.

[Zai]

I wouldn't expect a marine supplier to recommend a brand he doesn't sell either.

All I can say is that I have been using mine for three years now with no problems.

Anyone who wants to see my installation and hear it run is welcome to drop in and take a look.

I can say that I was set on a Spectra but was having difficulty with the cost of it and when I was looking it was only 7000 USD.

Went to the boat show in Dusseldorf and saw how many other companies were producing a similar one, I decided to give this one a go. Glad I did!

Each to his own!

[sy_gilana]

Originally Posted by Tellie

Spectras Cape Horn Extreme is 16Watts per gallon. Be careful on some of the above claims.

I still don't understand how you can mix metaphors, or units like that.

I will be very careful of anyone who calls a product "Gay Porn Extreme"
Does it come with bumhole chaps?



Seriously, 16 watts per gallon, its not possible. 16 watt/hours maybe.

The measurement is wrong, can someone please clarify.

[newhaul]

Originally Posted by sy_gilana

I still don't understand how you can mix metaphors, or units like that.

I will be very careful of anyone who calls a product "Gay Porn Extreme"
Does it come with bumhole chaps?



Seriously, 16 watts per gallon, its not possible. 16 watt/hours maybe.

The measurement is wrong, can someone please clarify.

it's the spectra cape horn extreme
https://www.spectrawatermakers.com/u...rn-extreme-330
Do the math it works out to 16wh per gallon.

[LeaseOnLife]

Originally Posted by newhaul

https://www.spectrawatermakers.com/u...rn-extreme-330
Do the math it works out to 16wh per gallon.

You are correct, but even their spec sheet lists 16w per gallon. It REALLY should be wh/gallon.

[Paul L]

Originally Posted by Franziska

One thing though, I would think there are also cultural differences in water usage between US and Europe.

This is not meant as criticism but water usage on US boats is very likely higher, because people are more used to it.
I'd think the average European boat might well get along with slightly smaller desalinators than the average US boat.

Just as Europeans tend to be more often happy without an air conditioning.

Just a thought.

Are you including all those large Euro owned cats curing the world?