Solar Hot Water

[clarity36]

Crew
Has anyone out there in cruising land built, or witnessed a deck mounted solaR water heater? I'm looking around for ideas for Clarity, and if it's been done successfully already, I'd appreciate knowing about it. Cheers. Bill

[resilientg]

best system that i have seen is one that use glass vacuum tubes, you can buy em as there designed for houses but only about 2 foot by 2 foot, or you can buy the vacuum tubes straight of the net and make your own system.

*** google hotwater vacuum tubes etc

Alternatively the tubes themselves aren't hard to make, you just need a few flower vases or bottles that fit inside each other, some epoxy and a vacuum pump.

*** youtube that one if you like

Anyway regarding the water temp, these things will heat water in the shade, so you be the judge.

when i get around to it, they will be the system that i will install on the targa of my boat, and ill only use two tubes.

Matthew

[Randyonr3]

saw one on a boat a couple years ago.. he had run his line from the pump up throu a series of black PVC tubes of about 2 inch beside his solar atop his arch..
The down side, as he said was that he didnt have hot water until early afternoon..

we'v e been addressing this for some time now and finelly purchased an "on demand" propane system from eco-temp.. havent installed it yet but the feed back was good on those we inquired about..

[stevensuf]

you can get dual solar panels, ie solar for electric on top and coils built in to heat up hot water as well, saves space and makes the panels more efficient a win win situation.

[czar]

Take a look at Heliatos. They make water heating panels for the marine crowd. Solar Water Heaters

[sailorchic34]

Originally Posted by stevensuf

you can get dual solar panels, ie solar for electric on top and coils built in to heat up hot water as well, saves space and makes the panels more efficient a win win situation.

I thought of that 20 years ago. but the solar PV panels have a temperature coefficient that basically looses 1V for each 20 degree f temp rise (above 66 degrees F).

For those wanting to experiment, for a flat copper plate/ tubing hot water collector, you need very roughly 5/8 to 3/4 sf per Gallon of hot water a day.

A simple copper, steel or aluminum tank ( painted black) on the cabin top, in a insulated box with a glass top would work too. Plastic pipe might work, but plastic is a bit more of an insulator so takes longer to heat the water within.