Realistic sized desalinator (water-maker)

[newhaul]

Originally Posted by Subtandard

Based on experience, about the minimum amount of water you can get by on is 5 liters per person per day. That is being very tight with water usage and few people would be happy with it. There is no limit to how much water you can use. It comes down to life style.

the minimum amount of water per person per day survival and comfortably are 2 very different numbers and are also dependant on where you are located.
I can get by on less than 2 Lyra per day in high latitude sailing . In the tropics 5 litre a day would be extra conservative .
There is actually a limit to how much you can use in a day . It is the capacity of your pumps. On my boat that equals 2160 us gpd. (My pressure pump delivers up to 1.5 gpm.)

sharing the shower with your significant other will definitely have an impact as well.
Shared showers make for happier sailing .

[bradm85]

I bought a Rainmain portable watermaker and love it. I timed it and in the PNW where the water is colder it filled a 5 gallon jug in just under 9 minutes so that is just over 33 gallons an hour. They have 2 models-one is gas and the other electric. I went with the gas and just set it up on the bow and run it at anchor. See it here www.seataskgroup.com

[svandante]

As if you need another bit of info, but I’ll toss it in the ring. The two important issues here are
1: how much water will you use per day.
2: how do you manage your power.
The latter is most important. If you use solar then you may get a small gph unit even as small as 5-6 gph and run with low drain for several hours every 1-3 days. (They do like to work, not sit idle). If you use engine or genset for battery charging, a larger unit (20-30 gph) and run only for 1-2 hours when the genset is running. Smaller use 12 volt and are quite efficient and quiet. Larger units are best driven with 120/240 volt motor, tend to be loud but also quite efficient and lower maintenance than 12 volt motor.
You should keep in mind the backflushing required. It makes little sense to run a unit every day producing X gallons of water but then use 1/4-1/3 of that to back flush the membrane. With this in mind, it is often better to run every 2-4 days for longer time.
Also the output of the membrane decreases substantially in colder water. Keep this in mind if cruising away from the tropics.

[neptunesjester]

Originally Posted by coopec43

I am busy installing the water tanks right now. I had planned on three tanks down inside the keel plus four "wing-tanks" but have now discarded the wing tanks because I realize I need to increase the size of the house battery bank to 4 X 135 Ah (and I need the room). The three remaining tanks will have a capacity of around 105 US gallons (390 L).

I've looked for threads on desalinators for yachts but they are all technical. My questions are:

• How many liters per day (or per hour) is a realistic size?
• Has anyone had feed-back on the kits available for people who prefer to DIY

https://www.ebay.com.au/itm/Boat-des...frcectupt=true


Clive

I sized my watermaker off my use. First I bought a flow meter and tracked how much water I was putting in my tanks for 2 months and arrived at my average daily usage without any water conservation techniques (long hot showers, running the dishwasher and using the washing machine for on oars laundry, etc).

I then sized my watermaker to produce complete replacement water every three days with running the generator no more than 4 hours.

I arrived at a 40 gallon (US) / hr watermaker. This has kept up well with my use even with derating due to lower water temps in the winter. I have an OCD wife that cleans constantly...lots of water use.

I went with the CruiseRO unit. Installation was straightforward and their customer service is outstanding.

I'm currently 70 days and counting from touching a dock and haven't needed to ferry water jugs once.

[coopec43]

Originally Posted by svandante

As if you need another bit of info, but I’ll toss it in the ring. The two important issues here are
1: how much water will you use per day.
2: how do you manage your power.
.

Thanks for that: I'll certainly keep that in mind

Clive

[coopec43]

Originally Posted by neptunesjester

..........rs laundry, etc).

I then sized my watermaker to produce complete replacement water every three days with running the generator no more than 4 hours.

I arrived at a 40 gallon (US) / hr watermaker. This has kept up well with my use even with derating due to lower water temps in the winter. I have an OCD wife that cleans constantly...lots of water use.

I went with the CruiseRO unit. Installation wa...........

Well I'm not as methodical as you but my wife is OCD too! The unit I have decided on has an output just a bit more than yours so it looks like I'm on the right track.

Thanks

Clive

[Redreuben]

Just do the experiment,
live for a weekend as if you were on board and measure your water, buy a loflow shower head like you would have on board and measure, or use a bucket if no on board shower, cook, wash up, clean some gear and keep track of what you use. Decant 50 litres into containers and see how far it gets you.
It will give you a much better idea than advice from a forum.

[coopec43]

Originally Posted by Redreuben

Just do the experiment,
live for a weekend as if you were on board and measure your water, buy a loflow shower head like you would have on board and measure, or use a bucket if no on board shower, cook, wash up, clean some gear and keep track of what you use. Decant 50 litres into containers and see how far it gets you.
It will give you a much better idea than advice from a forum.

I think I'm a pretty ordinary person so I'm happy to find out what others are using. But I'll have to e'rr on the high side as I'd expect to have "a crew" a lot of the time.


Clive

[rickwest]

Only you really know how much water you need..some.cruisers.use 10 gallons a day some a 100 gallons...also depends on the power to run a watermaker and for how long..I use to run my.small watermaker around noon off my solarpanels now I have a bigger unit and I need to have the engine runnning

[mfahrenthold]

There is an inexpensive water maker(s) here:
https://seawaterpro.com/

[newhaul]

Originally Posted by mfahrenthold

There is an inexpensive water maker(s) here:
https://seawaterpro.com/

the biggest issue is the cheap system uses a pressure washer that is not designed to run sea water so it won't last very long ( perhaps a single or possibly 2 seasons at best.
If you go this route spend the extra grand for the stainless pump

[Cpt Mark]

Originally Posted by xbillaroo

This season I will be replacing most parts in the Clark pump with their rebuild kit.

Can you provide the model number for that pump please?

I talked with Sea Water Pro a lot. Last year he had an all bronze pump as an upgrade option and told me in over 200 units sold, he'd never had an issue with the cheap Karcher pump and he'd had issues with the bronzen pump and recommended not buying it. Now he's saying the Karcher pumps last 2 years and is selling a SS pump. Not sure SS pump is better than bronze, actually think it isn't.

I've always thought the weak point in his design was the pump. It's clever what he came up with but I'd rather put in a great quality pump and not have to worry about replacing it on a regular basis.

[carstenb]

Originally Posted by coopec43

I am busy installing the water tanks right now. I had planned on three tanks down inside the keel plus four "wing-tanks" but have now discarded the wing tanks because I realize I need to increase the size of the house battery bank to 4 X 135 Ah (and I need the room). The three remaining tanks will have a capacity of around 105 US gallons (390 L).

I've looked for threads on desalinators for yachts but they are all technical. My questions are:

• How many liters per day (or per hour) is a realistic size?
• Has anyone had feed-back on the kits available for people who prefer to DIY

https://www.ebay.com.au/itm/Boat-des...frcectupt=true


Clive

you could start by reading this thread

http://www.cruisersforum.com/forums/...ose-93582.html

[44'cruisingcat]

Originally Posted by newhaul

ok now we are getting somewhere . With what you have listed I would say use 1/3 of your current water usage as a base point . And work from there .

I don't think that is realistic at all. In Sydney in summer we used to use 1200 litres a day! Watering lawns, veggies, washing cars etc. Automatic sprinkler systems, washing machines, dishwashers, swimming pools, spas....

On the boat it's around 40 litres per day.

[newhaul]

Originally Posted by 44'cruisingcat

I don't think that is realistic at all. In Sydney in summer we used to use 1200 litres a day! Watering lawns, veggies, washing cars etc. Automatic sprinkler systems, washing machines, dishwashers, swimming pools, spas....

On the boat it's around 40 litres per day.

1200 lpd ? How many people how much land?
That's over 3,000 gallons

you really added that much water to your pool daily.
40 lpd is not that unrealistic for a hot summer day for " x" people ( you don't say) so I will assume 4 people then 10 lpd per person isn't that far off with a daily shower each.

The truth is I was trying to politely talk him into actually looking at his consumption.