Hot Water First Thing in the Morning

[mvthankful]

What do you do? My hot water does not stay hot through out the night. I have a power boat with 520 watt solar, 880 am hr battery bank and 3000 watt inverter. I know that I can put a wash cloth and/or a bowl of water in the micro and I can boil water on the cook top. What else is there if I'm on the hook for a month? Oh yeah, my generator is a little honda 2000 that I prefer not to use!
Help me help my wife Deborah.

[Vasco]

You've covered all the ways to get hot water except sunshowers but they need sun so they won't be ready in the morning. You might run the engine. Why do you need hot water first thing in the morning when you're at anchor? I would try heading south.

[mvthankful]

Thanks Rick. Actually I will be heading to Mexico. Let me expand my question to; what do you do for hot water any time of the day while at anchor. I can also use my hydronic heater to heat my water heater but again I would rather not.

[Cheechako]

The only thing I can think of for your situation is a little Eccotemp L5 propane on demand heater. They have great reviews and are cheap. They are intended for outside and come with auto ignition and a shower faucet and hose. Under an overhead hatch etc would be fine I would think if inside. The little L5 does not require a vent, just has a little heat shield. They are less than $150. On a trawler etc, you could even mount it outside on a bulkhead etc if the inside thing bothers you. I used this type of heater in the mid 80's when I was in mexico. I mounted it in the head on the wall and just opened the overhead hatch when using it. These new ones now are much better with auto ignition and more consistant water temperature.

[Vasco]

We usually use a sunshower and shower late in the day before cocktail time. The water is usually very hot as we keep it in the sun and out of the breeze. Many folks get those black garden sprayers, they work well too. Sometimes we boil a kettle on the stove, usually to do the dishes. I've never used my Honda and don't run my engine.

[Jentine]

I have a KISS wind generator that charges the batteries and when they are up to par, switches to heating water. We generally have hot water all the time, especially when the sun shines and the wind blows.

[Cheechako]

How does a wind gen make hot water?

[CarlF]

What temperature does your water reach? How much insulation on the tank.

I have a SuperStor. The water reaches more than 140 degrees when the engine runs and is still really hot the next morning. On Superstor's web site they say that their tank loses 0.4 degrees (F) per hour. In a 36 hour test it only dropped 17 degrees. They say they have 2" of foam.

Maybe just wrapping a little more foam around your tank would do the trick. Or use several layers of the foil bubble-wrap insulation you can buy at HD.

Carl

[GordMay]

Originally Posted by Cheechako

How does a wind gen make hot water?

The wind turbine generates electricity, which powers a 12VDC resistance heater (water tank element).

Wind Turbine Dump Load (diversion load, shunt load)

Whereas solar-electric modules can be turned off—open circuited—with no damage; most wind generators should not run unloaded. They will run too fast and too loud, and may self-destruct. They must be connected to a battery bank or load. So normally, a charge controller that has the capability of being a diversion controller is used. A diversion controller takes surplus energy from the battery bank and sends it to a dump load. In contrast, a series controller (commonly used in PV systems), actually opens the circuit.

A dump load is an electrical resistance heater, and it must be sized to handle the full generating capacity of the wind generator used. These dump loads can be air or water heaters, and are activated by the charge controller whenever the batteries or the grid cannot accept the energy being produced.

[zeehag]

in the morning i boil it on stove and later in the day i have a solar water shower bag...LOL...they work just great--i discontinued m y water heater --i donot like those things--they always leak and are not able to be repaired--mine were the square kind and leaked within 6 months if installation....so i go with solar showers..i have 2 on board....

[Randyonr3]

Gord
If I remember right we went through this type of system a couple years ago when I installed my system.. I was jazzed when I set up my wind charger (4-winds) to a morningstar deverter with a dump load to heat the water..
When we figured the power it would take to heat the water, even just a few degrees, using the wind charger, It turned out to be almost a joke..
I've been running mine now for a couple years and at the best, it only takes the chill off the water.. The "dump" system I have on mine is the same as used on the "Kiss" system..
I fought the hot water delima also and what I have installed is a series of tubes along side the solar pannel that I circulate the water through durring mid day..
some friends of ours would take the kids inflatable boat and tye it along side the large boat and start the motor.. all the water comming out of the exaust would fill the little boat with hot water.. after it was full they would pull it around back and let it set for a few minutes to "Gas Off" so-to-speak and then the kids would use it to take a bath in.. She had even told my wife that it was better than a shower inside for her to shave her legs as she could set in the little inflateable, with her leg up on the sides of the boat..

[Cheechako]

Yea, that was the part I didnt understand, I didnt even know they made a 12volt element.. gut feel says..."HUH?"

[GordMay]

A 300 Watt (23 Amps @ 13V) Heating Element is capable of heating 6 gallons of water from an ambient of 75 F. to 120 F. in about 2 hours. As Randyonr3 notes, that’s a pretty large output to expect from a small turbine.

12VDC Water Heater Elements:

➥ Diversion Loads @ Survival Unlimited.com - Water Heater Elements, Air Heaters, DC water heaters, DC air heaters

➥ 31 Water and Air Heating Diversion Loads for Charge Controllers

[ColdFusion]

Why has there been no mention of diverting the power from solar panels too, as well as a wind gen, once the batteries are charged, or have I missed something? I appreciate they'll only work during the day but with enough insulation on the calorifier/hot water tank the water should still be hot in the morning. So why not use solar panels to power the heating element too?

[GordMay]

Originally Posted by ColdFusion

Why has there been no mention of diverting the power from solar panels too ... So why not use solar panels to power the heating element too?

It's not necessary with solar cells, which can be open circuited.
Other than the very small return (you’ll need a minimum of 300 Watts to be of any appreciable use), there’s no reason you couldn’t switch the PV output to water heating, when not needed for charging.