Liveaboard watermaker facts and figures

[geem]

For anybody contemplating a watermaker and their likely consumption.
With two people living aboard in the Caribbean. Shower every day. Normal cooking a washing clothes onboard. We dont have a washing machine but we have two large builders buckets and a White Knight spinner.
Checking our water consumption over a season based on the last two seasons.
We use 30 litres per day. We have a watermaker that makes 130 litres per hour via a diesel generator and 220v pump.
Our generator hours work out at 15hours per month but that also includes running it for vacuum cleaning and making a tank of hot water occationally.
We plan to fit another 40" membrane housing this summer than will bring our output to circa 200 litres per hour and therefore reduce generator hours. We average 100 hrs per season on the generator which fits nicely into the annual service interval at 100 hrs but less hours would be nice.
We use the first two gallons of product water to fill our solar shower or rinse the cockpit until the TDS reading drops to about 300 ppm.
Hope this is of use.

 

[BobnLesley]

Then again you could save all those costs associated with buying, maintaining & powering a watermaker and instead use a much smaller amont of beer-tokens to cover the cost of pulling up at the occasional fuel dock/marina and filling the tanks with a hose pipe. Remember: If you don't fit it, it can't break; if it's already fitted and working, then don't use it as it'll break.

 

[geem]

Then again you could save all those costs associated with buying, maintaining & powering a watermaker and instead use a much smaller amont of beer-tokens to cover the cost of pulling up at the occasional fuel dock/marina and filling the tanks with a hose pipe. Remember: If you don't fit it, it can't break; if it's already fitted and working, then don't use it as it'll break.

Well you could if you want to spend time going to get water if its available. We make it for a 5th of the cost at the marina over here. But its not the money its the convenience and knowing that the water quality is perfect unlike some of the poor water our friends have taken oboard in places like Antigua.
I built my watermaker from parts and will easily recoup the investment if I ever want to sell it which I suspect would only be when I give up this sailing life.
You seem to have a very pesimistic view of watermakers. Fit a simple Cat pump driven system and they are pretty bullet proof. We have made 5500 litres this season. At 1 litre/hr on the gen that works out at about £25 for a seasons water. We havent had to venture in to marinas or miss out places like Barbuda where you can get any. No struggling with cans and numerous trips in the dinghy as would be necessary in Monserat, Saba, Stacia, etc.
We wouldnt be without our watermaker. One of the best bits of kit on the boat.

 

[ip485]

Very interesting post, thank you.

We plan to be there this year and I am interested how our water consumption will go.

We have a very similiar water maker and Genset. The water maker is great, producing 140 litres per hour. I think we are lucky in that our tanks are reasonably large - we hold 300 galllons of fresh water and a seperate tank for the toilets whcih are also fresh water Vacuflush. We also have a full size domestic washing machine. Using nearly your rate of 10 gallons a day full tanks should give us 30 days without resorting to the water maker.

I wonder if our larger tanks and the ability to "bank" water will mean we dont need to increase our water making ability?

Interested in your thoughts?

 

[geem]

Very interesting post, thank you.

We plan to be there this year and I am interested how our water consumption will go.

We have a very similiar water maker and Genset. The water maker is great, producing 140 litres per hour. I think we are lucky in that our tanks are reasonably large - we hold 300 galllons of fresh water and a seperate tank for the toilets whcih are also fresh water Vacuflush. We also have a full size domestic washing machine. Using nearly your rate of 10 gallons a day full tanks should give us 30 days without resorting to the water maker.

I wonder if our larger tanks and the ability to "bank" water will mean we dont need to increase our water making ability?

Interested in your thoughts?

We have 200 gallon water capacity. Crossing the Atlantic we made water once we had dropped the tank to half full. We had four onboard for the last Atlantic crossing. We all showered everyday and lived life pretty normally. We made 1 ton of water onroute. We arrived with full water tanks.
You are not going to have a problem with your set up. You have plenty of capacity in your tanks. Interestingly we are adding another 40" membrane to our system this summer as it will up our watermaking to 200 litres per hour for no more fuel use and therefore reduce the generator run hours.
Once in the Caribbean we keep about 100 gallons in the tank. There is little point in carrying the extra water for no reason unless you are somewhere like Simpson Bay Lagoon in St Marten or Spanish Water in Curacao where the water is manky. In those places we fill the tanks before we go.

 

[Kelpie]

Accepted wisdom for watermakers appears to be to fit a big one and run it infrequently.
Does anybody go the other way, and fit a little one that can chug away in the background, running off excess solar capacity? Sounds more civilised and far cheaper, but I'm guessing there's a catch somewhere.

 

[Garry & June 'Friendship']

Accepted wisdom for watermakers appears to be to fit a big one and run it infrequently.
Does anybody go the other way, and fit a little one that can chug away in the background, running off excess solar capacity? Sounds more civilised and far cheaper, but I'm guessing there's a catch somewhere.

This is exactly the route we went...we spent ages looking at the different options and had brilliant correspondence with Jim MacDonald at Mactra...in the end we purchased a Katadyn Survivor 80e...it produces 13+ litres an hour for 8 amps of power...we get this power from our AGM battery bank and 400w of solar....we run it at anchor for 3 hours a day usually which gives us just under 50 litres although very often we don't need to run every day. Its not a huge unit so easy to install..and gives us water for zero daily running cost...oh and another important consideration is that water makers like to be run...not sit idle...so making hundreds and hundreds of litres and then not using it for a week isn't doing it any good.
We like to stay at anchor as much as possible in the summer months, having solar and the water maker means we can do just that.

 

[geem]

This is exactly the route we went...we spent ages looking at the different options and had brilliant correspondence with Jim MacDonald at Mactra...in the end we purchased a Katadyn Survivor 80e...it produces 13+ litres an hour for 8 amps of power...we get this power from our AGM battery bank and 400w of solar....we run it at anchor for 3 hours a day usually which gives us just under 50 litres although very often we don't need to run every day. Its not a huge unit so easy to install..and gives us water for zero daily running cost...oh and another important consideration is that water makers like to be run...not sit idle...so making hundreds and hundreds of litres and then not using it for a week isn't doing it any good.
We like to stay at anchor as much as possible in the summer months, having solar and the water maker means we can do just that.

Run it for half an hour at a time and its good for three days before you run it again. Big is beautiful

 

[sailaboutvic]

We build a similar set up to geem , we getting around 70 to 80 lts an hour after taken away what is used to back wash .
Does it justify having one in the Med ?.
Well there two ways of looking at it .
1 .. sailing in the. Med for well over 22 years we never had a problem getting water without paying for it , last year we paid no more then 20 euros , the year before about the some , most of the time we found a tap some where but we had to carry it in containers .
2.. my back isn't what it use to be and I spend weeks taken pain killers after carrying water , yes we could had gone into a Marina and use a pipe but more and more Marina now have token meters and by the time you mess about with going to buy a token which meant leaving a deposit then taken it back to recover the deposit as well as losing what every credit left on it that's with out waiting around for a spot to moor up .
And there are some Marina that now won't sell you water unless you take a berth , so there is a lot of messing around at Marina .
In the end I weightup what's important to me , my back or the money to build one , no contest.
My only one regret is , that I did try the route of using a water pressure motor/ pump rather then a cat pump , in which case I could run it off an invertor , instead of the gen set , althought I might at some point convert my pressure washer to see if it would work in case we did need to use it .
Don't laugh guys but is going to take a long time to recover our cost but the cost is slowly going down ,
Although we do charge stuff up and make hot water as well as at time cook while the gem set working .
Fresh water is now used to flash the heads , we don't have to pay to use washing machine and our showers are much longer .
SO if your young and fit or old and fit and hanging around in the Med and don't mind carrying water or if your a Marina yachtie that used them regularly don't bother with a water maker ,
Just in case you are plainning to make one , our cost us 2K to build , useing a cat pump and a 1.5 kw motor , the cat pump is what cost the most .
You could almost half the cost by using a washer pump but you may have to replace it every couple of years and run it off an inverter.

 

[jordanbasset]

Wonder if we are one of the smallest boats to have a water marker. We have a 2013 Bavaria 33 and the original owner got an an eco tec water maker fitted when it was commissioned. Originally I thought it was completely OTT (it has 4 filters plus the membrane itself) and unnecesaary in the med and it is really, but the luxury of using as much water as we want without worrying about it is a very nice extra.

 

[Gerry]

This is exactly the route we went...we spent ages looking at the different options and had brilliant correspondence with Jim MacDonald at Mactra...in the end we purchased a Katadyn Survivor 80e...it produces 13+ litres an hour for 8 amps of power...we get this power from our AGM battery bank and 400w of solar....we run it at anchor for 3 hours a day usually which gives us just under 50 litres although very often we don't need to run every day. Its not a huge unit so easy to install..and gives us water for zero daily running cost...oh and another important consideration is that water makers like to be run...not sit idle...so making hundreds and hundreds of litres and then not using it for a week isn't doing it any good.
We like to stay at anchor as much as possible in the summer months, having solar and the water maker means we can do just that.

We too have the Katadyn and run ours from a KISS wind generator. Tanks onboard hold just over 500 litres and we have four 20 litre cans on deck... We can also catch rain on the decks to fill two of our three tanks.
In 17 years of cruising we have never had to run the engine in order to run the watermaker to fill the tanks. The watermaker has proved it's worth a number of times when access to water has been limited either by weather, anchorage or price. It's a useful bit of kit to have.
Crossing the Atlantic with the two of us aboard we generally use less than half the water we carry. Mind you if there is no rain for an on deck shower we can be pretty smelly when we arrive!

 

[geem]

We too have the Katadyn and run ours from a KISS wind generator. Tanks onboard hold just over 500 litres and we have four 20 litre cans on deck... We can also catch rain on the decks to fill two of our three tanks.
In 17 years of cruising we have never had to run the engine in order to run the watermaker to fill the tanks. The watermaker has proved it's worth a number of times when access to water has been limited either by weather, anchorage or price. It's a useful bit of kit to have.
Crossing the Atlantic with the two of us aboard we generally use less than half the water we carry. Mind you if there is no rain for an on deck shower we can be pretty smelly when we arrive!

On our last boat we had a Katadyn. It did its job and made us water but at times we felt like a slave to the watermaker. We would have to run it for several hours at a time. We had solar power and a wind turbine. I was always reluctant to leave it running and go ashore as you never new what might go wrong. We also found that we really needed more solar power. When the sun was unbroken it worked perfectly but on cloudy days we would not have enough sun to keep up with the watermaker demand. We went through batteries as I believe we were under charging them without realising due to the long hours on the watermaker. I think if we had gone the 12v route now we would have more solar but there is a limit to how much solar you can install on a monohull. I think if you are on a cat with huge deck space then the 12v route can work very well as you can easily install lots of solar. We met a guy with 1000w of solar on his cat and a 12v watermaker who had so much space charging capacity he could run it on cloudy days all day and still charge his batteries completely. I think if you go the 12v watermaker route it is worth making sure you have very good battery monitoring to ensure you are looking after your batteries. The £25 fuel cost per season of making over 5 tonnes of water via the generator are tiny compared to replacing the 900 amp hr battery bank if we abuse it.

 

[Billyo]

Can anyone recommend some good literature or guide that they have used on how to DIY a system? I would be very interested in doing it on my next boat.

 

[Ric]

We build a similar set up to geem , we getting around 70 to 80 lts an hour after taken away what is used to back wash .
Does it justify having one in the Med ?.
Well there two ways of looking at it .
1 .. sailing in the. Med for well over 22 years we never had a problem getting water without paying for it , last year we paid no more then 20 euros , the year before about the some , most of the time we found a tap some where but we had to carry it in containers .
2.. my back isn't what it use to be and I spend weeks taken pain killers after carrying water , yes we could had gone into a Marina and use a pipe but more and more Marina now have token meters and by the time you mess about with going to buy a token which meant leaving a deposit then taken it back to recover the deposit as well as losing what every credit left on it that's with out waiting around for a spot to moor up .
And there are some Marina that now won't sell you water unless you take a berth , so there is a lot of messing around at Marina .
In the end I weightup what's important to me , my back or the money to build one , no contest.
My only one regret is , that I did try the route of using a water pressure motor/ pump rather then a cat pump , in which case I could run it off an invertor , instead of the gen set , althought I might at some point convert my pressure washer to see if it would work in case we did need to use it .
Don't laugh guys but is going to take a long time to recover our cost but the cost is slowly going down ,
Although we do charge stuff up and make hot water as well as at time cook while the gem set working .
Fresh water is now used to flash the heads , we don't have to pay to use washing machine and our showers are much longer .
SO if your young and fit or old and fit and hanging around in the Med and don't mind carrying water or if your a Marina yachtie that used them regularly don't bother with a water maker ,
Just in case you are plainning to make one , our cost us 2K to build , useing a cat pump and a 1.5 kw motor , the cat pump is what cost the most .
You could almost half the cost by using a washer pump but you may have to replace it every couple of years and run it off an inverter.

You can still get by easily in the Med without a water maker - but I have noticed in recent years that many marinas now charge for water (routinely in Italy and Spain, now increasingly so in France - e.g. Hyeres) there is less and less tolerance to freeloaders going into other marinas and topping up without paying. If you are Del Boy type who doesn't mind the slight shame of getting disapproving stares or the occasional sarcastic comment, then this may not matter. But I am a bit sensitive to that sort of thing and can't bring myself to fill up with water without asking and giving something.

Anyway, I have now fitted a small water maker (PUR40E) which makes about 5l per hour, to augment my occasional dock water fills. My daily consumption (single handing in Med with frequent deck showers, rinse downs) averages about 15l/day. I draw water for showers and clothes washing from the dock water tank, and have a separate tank for the water maker outlet which I use for cooking and drinking water. It is really nice never having to be slave to port visits, especially in Italy where I find marinas expensive and unpleasant.

 

[geem]

You can still get by easily in the Med without a water maker - but I have noticed in recent years that many marinas now charge for water (routinely in Italy and Spain, now increasingly so in France - e.g. Hyeres) there is less and less tolerance to freeloaders going into other marinas and topping up without paying. If you are Del Boy type who doesn't mind the slight shame of getting disapproving stares or the occasional sarcastic comment, then this may not matter. But I am a bit sensitive to that sort of thing and can't bring myself to fill up with water without asking and giving something.

Anyway, I have now fitted a small water maker (PUR40E) which makes about 5l per hour, to augment my occasional dock water fills. My daily consumption (single handing in Med with frequent deck showers, rinse downs) averages about 15l/day. I draw water for showers and clothes washing from the dock water tank, and have a separate tank for the water maker outlet which I use for cooking and drinking water. It is really nice never having to be slave to port visits, especially in Italy where I find marinas expensive and unpleasant.

Ric, it is interesting that you average about the same consumption as ourselves. Two onboard works out at 30litres per day over the season. We dont make a huge effort to save water but we dont waste it either.

 

[geem]

You can still get by easily in the Med without a water maker - but I have noticed in recent years that many marinas now charge for water (routinely in Italy and Spain, now increasingly so in France - e.g. Hyeres) there is less and less tolerance to freeloaders going into other marinas and topping up without paying. If you are Del Boy type who doesn't mind the slight shame of getting disapproving stares or the occasional sarcastic comment, then this may not matter. But I am a bit sensitive to that sort of thing and can't bring myself to fill up with water without asking and giving something.

Anyway, I have now fitted a small water maker (PUR40E) which makes about 5l per hour, to augment my occasional dock water fills. My daily consumption (single handing in Med with frequent deck showers, rinse downs) averages about 15l/day. I draw water for showers and clothes washing from the dock water tank, and have a separate tank for the water maker outlet which I use for cooking and drinking water. It is really nice never having to be slave to port visits, especially in Italy where I find marinas expensive and unpleasant.

Ric, it is interesting that you average about the same consumption as ourselves. Two onboard works out at 30litres per day over the season. We dont make a huge effort to save water but we dont waste it either.

 

[AntarcticPilot]

Well you could if you want to spend time going to get water if its available. We make it for a 5th of the cost at the marina over here. But its not the money its the convenience and knowing that the water quality is perfect unlike some of the poor water our friends have taken oboard in places like Antigua.
I built my watermaker from parts and will easily recoup the investment if I ever want to sell it which I suspect would only be when I give up this sailing life.
You seem to have a very pesimistic view of watermakers. Fit a simple Cat pump driven system and they are pretty bullet proof. We have made 5500 litres this season. At 1 litre/hr on the gen that works out at about £25 for a seasons water. We havent had to venture in to marinas or miss out places like Barbuda where you can get any. No struggling with cans and numerous trips in the dinghy as would be necessary in Monserat, Saba, Stacia, etc.
We wouldnt be without our watermaker. One of the best bits of kit on the boat.

Obviously YMMV, but I pay about £8 for 5.5.cu m of good potable tap water in the UK. Agree that when off the beaten track a watermaker is a good idea, but if mains water is accessible it very quickly looks a poor deal.

 

[sailaboutvic]

Obviously YMMV, but I pay about £8 for 5.5.cu m of good potable tap water in the UK. Agree that when off the beaten track a watermaker is a good idea, but if mains water is accessible it very quickly looks a poor deal.

I think most people would agree with you , it's a bad deal , but having it on tap so to speak and not having to worry about it or how much you have is a big plus ,
If you sail around Malta unless you took a berth I can't think of any of the Marinas that will sell you water ,
You could look at it another way , why have an outboard motor costing hundreds plus you have to use fuels as well , when you have two good oars ?

 

[BobnLesley]

...when off the beaten track a watermaker is a good idea, but if mains water is accessible it very quickly looks a poor deal.

Well, at least partial support to the Luddite cause and probably my opinion too. In 14 years sailing the Med/Caribb/N&S America we've never 'run out' of water, nor had to adjust our cruising plans to obtain any, but I'll accept there have been times when we needed to be very aware of our consumption and/or even actively conserve our water. To me, the trade-off with a watermaker is the additional availability - could achieve that by moving back ashore - against the costs both financial and in space/weight (we're only a small boat) and an additional maintenance cost/concern. Watermakers do seem to have improved markedly in recent years, but they along with fridges/freezers still seem high on the list of items that have people altering their cruising plans to get somewhere for repairs. I wonder if my 'not for us' opinion will survive the Pacific?

 

[BobnLesley]

...when off the beaten track a watermaker is a good idea, but if mains water is accessible it very quickly looks a poor deal.

Well, at least partial support to the Luddite cause and probably my opinion too. In 14 years sailing the Med/Caribb/N&S America we've never 'run out' of water, nor had to adjust our cruising plans to obtain any, but I'll accept there have been times when we needed to be very aware of our consumption and/or even actively conserve our water. To me, the trade-off with a watermaker is the additional availability - could achieve that by moving back ashore - against the costs both financial and in space/weight (we're only a small boat) and an additional maintenance cost/concern. Watermakers do seem to have improved markedly in recent years, but they along with fridges/freezers still seem high on the list of items that have people altering their cruising plans to get somewhere for repairs. I wonder if my 'not for us' opinion will survive the Pacific?