Small Solar Power system

[riptides]

Instead of a heater, get a large aquarium/small pond bubbler that will draw no more than 15-25 watts.

Wow. Yeah I have all sorts of koi/aquarium/water pumps around. No where near the wattage of the heater. Will have to see how horses react to - bubbly water. LOL.

For the outside lights, heck for 50 bucks I can get self contained solar units. I might try that route in the meantime while I figure this out.

 

[Diggin It]

For the outside lights, heck for 50 bucks I can get self contained solar units. I might try that route in the meantime while I figure this out.

Or less:

 

[John_Mc]

I wonder if you might be better off going with solar hot water, rather than electrically heating your water. I have a couple of 4'x8' panels that act as a preheater for my domestic hot water tank. The antifreeze is circulated through them by a solar powered pump run by a small solar panel (roughly 12' x 16" panel, no batteries, the pump runs whenever the sun shines). The panel also powers the control system that decides whether the pump runs or not (it won't run if the solar collector temp is below my holding tank temp, or if my holding tank is at it's max safe temperature).

My system is overkill for what you need (even one of my panels is probably overkill), but something similar in your setup probably makes more sense than trying to heat the water electrically. There would be no battery backup, but you'd be able to keep your water thawed even on moderately sunny days where there is not enough electric power to run your 1500 watt heater.

Your system would consist of some sort of solar thermal collector, a small pump and PV panel, control system (so pump doesn't run when collector is colder than your tank, or when tank is already at your max desired temp), plumbing, and a heat exchanger that you drop into your tank (since you should probably run antifreeze in your heat exchanger, you may want a double walled heat exchanger to provide extra isolation of the antifreeze from your water).

Couple that with the self contained solar lights you linked, and you might be in pretty good shape.

 

[MossRoad]

The trough heater is the issue. How big? How much surface area? How much Sun do you normally get? How much loss is there due to shade from trees, buildings, terrain, etc.?

There are solar pool heaters that lay out on the ground and circulate the water through them via a small pump. If you get enough Sun and temperatures don't too bitter cold, that may be an option.

A solar pool heater, left with water in it on a freezing night, can burst pretty quick. So can any pool pump or filter.

 

[Travelover]

I'd agree that the way to get solar heat is to directly capture the heat from the sun. In a place where it freezes, you need a system that has separate antifreeze to capture the heat, then a copper coil in the trough to transfer the heat, with a tiny pump to circulate the working fluid. Just a couple gallon can painted black would suffice as a solar collector. Insulate the trough, too, of course.

 

[RoyKing]

How about solenoid valve and a freeze alarm , turn on the water and let it run. Much less complicated

 

[John_Mc]

From my friend, who is a renewable energy guru (used to run a Solar PV installation company using systems he custom-designed, formerly designed wood combustion systems and control systems for them):

Going with a solar water heater and enough thermal mass would definitely be the most cost effective solution. There was a batch of solar hot water panels being sold used from a large food processing facility in the past. They may be a good source for panels if your other friend doesn't want to make a panel.

If it were me ... I would insulate the stock tank and have a second, fully closed & insulated tank with a gravity feed to move water to the drinking tank as needed. The second tank would be the thermal mass to get through the one day storage you mentioned.

Alternatively, would a temperature triggered electric circulator and sufficient thermal mass be the low cost solution for a climate like VA?

BTW, making your own solar hot water panel is not at all difficult. A local friend made his own, which provides the majority of his domestic hot water here in Vermont. If you search solar hot water on YouTube, you'll find lots of DIY examples. You don't need a lot of capacity, since you are just looking for freeze protection, rather than hot water for a shower or similar use.

 

[Travelover]

These might be of use. Build a Solar Stock Tank - DIY - MOTHER EARTH NEWS

Solar heated and insulated stock tank

Suntanks: Freeze-proof Solar Heated Horse Waterers,Cow Water Tanks

Build a Solar Stock Tank - DIY | On The Farm | Pinterest | Livestock, Horses and Farm life

Solar Heated Stock Tanks - Shipping Nationwide!

https://www.amazon.com/Gallon-Suntank-Heated-Livestock-Manual/dp/B07261G4V2

https://www.builditsolar.com/Projects/WaterHeating/SteveTank/SteveTank.htm

 

[Industrial Toys]

Funny how the whole Solar Power consideration comes to a grinding hault when someone mentions "heat". Most solar installations for heat, are through circulating panels. I'm guessing the efficiancies are higher, than making electricity and heating water that way.

 

[riptides]

This experience is interesting. For lights it is a no brained to spend less than 100 dollars for decent flood light type bulbs. For indoor lighting about the same for a few bulbs. For a water heater. .... it is more complicated as now we need wattage and a good battery system. I will insulate the tank and run an extension cord as needed until I figure out a better low cost less hassle solution.