Thanks for the nice words Dave, I'm blushing...
There really isn’t a “wrong choice” between a 12v or 120v water maker as long as you know the strengths/weaknesses of each approach. What led Cruise RO Water
down the 120V high output water maker path was our personal experience while out cruising Mexico. Our friends with 12v water makers needed to run their diesel engine at anchor to have enough power to run their lower output 12v water maker long enough each day to keep up with their daily water usage. Not to exaggerate, there are plenty of cruisers with 12v lower output water makers that can make all the water they need from wind and solar, but I just haven't seen that to be the norm amoung the cruisers I taked to and shared anchorages with down in Mexico. Cocktail conversations always had their share of gear discussions and wanting a larger production water maker was something we kept hearing over and over. Now this is certainly not a ding on Spectra, which is a great water maker and their customer service is great, but more a reality that most cruisers don’t have enough wind or solar to keep up with their daily 12v demands.
Making 20 or 30 gallons of water per hour while running the generator 2-3 times a week to keep the tanks full makes a lot of sense for folks that realistically are going to have to charge with their generator anyway due to power consumption and the lack of room for enough solar to cover the load. If your generator fails, both the 20 and 30 gallon per hour water makers use the same amount of power and can be ran from a 2000W inverter while the alternator is running, so you do have a back-up in the event your generator goes down.
Here's a link to two of our client's Blogs that replaced their 12v 8GPH water makers with our 30 and 20 GPH water makers after running into the same power usage and water usage realities that we experiences ourselves. You can see his rational for the move and contact them through their blogs if you have questions for them:
SV Reach in Guatemala
SV Eagle in La Paz, Mexico
General Customer Feedback
Redundancy is a BIG deal while cruising, which I think is why the 30 gallon per hour water maker is our most popular selling unit. Not only is it 50% more efficient than the 20 in terms of fresh water production, if one of the two RO Membranes was to fail while out cruising the unit can easily be reconfigured and turned into a 20 gallon per hour unit. For $950 (with free shipping and no Tax from Mayberrys.com
) a Honda 2000 generator is also a great redundancy option for folks depending on a ships generator. Not only can it power the 20 and 30 gallon per hour water maker AND charge the battery at the same time, but we use the Honda a LOT more than our 8KW diesel genset frankly because it is more fuel economical, doesn’t put heat in the boat in Hot Mexico and is a LOT easier to do an oil change on than the diesel. Look around an anchorage and the shape of a Honda 2000 under a sunbrealla cover is as common as jerry jugs on deck.
Our Honda 2000 has lived on deck now for 5yrs. Even if I went with a 12v Spectra water maker (again a great water maker), I still would not cast off cruising without a Honda 2000 (or a ships genset). That’s just power hungry me who has a wife that would not be on her 6th year of living aboard is she felt like she was camping rather than cruising in comfort. I never once told her to take shorter showers. Instead, I start up the Honda when she gets out of her long shower for her hair dryer with a smile. I still take 1L showers, but that’s so I can run my power washer at anchor along with the fresh water anchor wash down…
The bottom line about not just water makers, but lots of cruising gear choices, there is not one right choice and a bunch of wrong choices. The important thing is understanding the options and then pick the gear that will fit into your cruising style. Sure I make and sell water makers for a living, so I would like people to choose my water maker. But when I was last anchored in La Paz, Mexico there were 8 other cruisers at anchor that had one of my water makers so the last thing I would want would be someone to have bought a 120v water maker without understanding it's strengths and weaknesses. I don't want to be run out of the anchorage!
So what are the weaknesses of a 120v water maker?
Forget about powering them off of wind/solar. You will need to burn fuel (gas or diesel) to make water (or as a back-up powered through a 2000W inverter ONLY when you motor is running and Alternator is putting out Amps). For some people this alone is a deal killer.
You will need to have a generator aboard. If you already have a diesel genset, then I think the 120v water maker is an easy choice. If not, then you are looking at adding a $950 Honda Generator to your boat or a $5K-$10K diesel genset.
There is a thinking out there that if you have too large a water maker then you will not run it enough to keep the membrane healthy. I don't agree with this, but to be fair, it is what some people say in discussing water make sizing. To me fresh water is like Chocolate, can you really ever have enough on board?
Rather than trying to explain, here is a Customer Complaint Email we received and the names have been redacted to protect the innocent!
From: [30 GPH Water Maker Client]
Sent: Saturday, December 21, 2013 4:34 PM
Subject: Damn you Rich
Yesterday we bought a small pressure washer for the boat because, as [my wife] put it, "since we can make enough water now, we can use it to keep the boat clean all the time" (by "we" she means "me", of course).
Now she is slowly slipping in comments about washing machines.
This is your fault, and is something you should make perfectly clear on your website regarding your high output water makers.
Thanks for making more work for me!
[30 GPH Water Maker Client]