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DIY Solar Powered Water Heater

Without the Sun, the Earth would just be a big dark ball of rock and ice floating through empty, desolate space. Nothing, or anyone you know, would ever have been. Nothing, or anyone, would ever be. There would be no life as we know it. Oh sure, it’s possible, maybe even probable, that there would still be some forms of life. But who wants to be a blind amorphous blob? But seriously, the Sun IS life.

About the Sun

Comprised mostly of 73% Hydrogen (H), and 25%Helium (He), along with traces of Oxygen (O), Carbon (C), Neon (Ne), and Iron (Fe), the Sun is a big fiery glowing ball of gasses burning at 10,000 degrees F (5,600C) on the surface and a whopping 27,000,000 degrees F (15,000,000 degrees C) at the core. It is 332,946 times the mass of Earth and fluctuates between 147,000,000 km (91.3 million miles) and 152,000,000 km (94.4 million miles) away, depending on the location of the earth in its elliptical orbit around the big fireball.

The Power of the Sun

Luckily, the Earth “happens” to be at just the right distance to have temperatures that are favorable to life. And if you’re even a little luckier, you’ll be enjoying the Sun at a beach full of pretty girls in bikinis. If you’re not so lucky, you’ll be hoping the sun melts the snow off your car so you can get to work on time.

However, if both of those things are nowhere in your itinerary because you’re homesteading off the grid or that pudgy boy with the funny haircut in North Korea just started WWIII, and then you will be thinking about the Sun in other terms. These terms will be along the lines of “How can I use the Sun to make my life easier”?

Sun Power (Aka Solar Power)

Harnessing the power of the Sun can be a practical tool in your quest for survival, and I don’t just mean you can dry your clothes on the line on a warm, breezy day. What other things can you use the Sun for you ask? Well, I’ll give you a few ideas right now. One way to do it is to make a solar water heater.

Solar Water Heater

Have you ever been washing the car on a hot summer day, then went in the house to get a drink or use the bathroom, etc? Remember when you came back out about 10 minutes later and sprayed the water, and it was hot as heck? Well, you experienced what is the basis behind solar hot water heaters, otherwise known as solar thermal exchange.

worm farming

You can use the Sun to make hot water by creating a simple system by various methods. There are commercial solar water heaters on the market that you can spend a ton of money on. These don’t contain water directly in the system. Instead, they have a liquid similar to the antifreeze that is in your car so that it won’t freeze in the winter.

greenhouse effect

This liquid is heated by the sun. It then circulates into a heat exchanger inside your house to use the solar heated liquid to heat your water. This type of system may be difficult to DYI, but for the very clever, it could be done. But there is a system that pretty much anyone can make themselves, although it may not work very well in the winter.

The basis behind a solar water heater is that cold water goes into a coil, or grid of tubing that is painted flat black, and enclosed in an insulated box. The front of this box is covered with a glass or Plexiglas front panel to allow the solar rays to pass into the box. Glass is better, but Plexiglas will work.

The green house effect holds this solar energy inside the box, and allows this grid to absorb the solar energy and heat the water within the system by solar thermal exchange. A typical gas or electric water heater inside the home holds anywhere from thirty to fifty gallons of water, this is generally enough hot water to supply a family of four. If you create a solar water heater with that capacity or more, then you can minimize (or maybe even eliminate) the need for a commercial water heater.

Here is a pretty good video of a homemade solar water heating grid:

Creating the heating grid is only half of the equation though. You still have to get the hot water inside the house. It is possible to tie it directly into your water heater. Your water heater works in a pressure system. Cold water enters the tank and is heated either by gas fire beneath the water heater, or by two electric heating elements inside the tank. A thermostat controls and maintains the temperature of the water in the system.

When you turn on the hot water, it opens a valve at the faucet and creates negative pressure in the system. This negative pressure causes more cold water to flow into the tank, and this pushes hot water out of the tank, and on to wherever you opened a valve (turned on a faucet).

Commercial Solar Water Heater

You can introduce this solar water heater into the system by one of two ways. The water that was heated by solar energy can go into a water heater inside the house as you use the hot water, rather than cold water entering the tank. This is a hybrid system. If cold water enters the tank, this necessitates energy use by means of fire or electricity to heat the newly entered cold water.

commercial solar water heaters

However, if pre-heated water from the solar water heater enters the water heater tank, then it doesn’t need to use any energy to heat it. The only energy needed will be to maintain the temperature inside the tank when the water is not in use. This energy is minimal. This method will cut your energy use to heat water by about 90%.

Here’s a video of a commercial hybrid solar water heater being installed and tied in to the water heater inside the house:

DYI Solar Water Heater

The second method of introducing the solar heated water into your system is directly. When you turn on a faucet, water comes directly from the solar heater and is replaced in the system by cold water, which will then be heated by the sun. This system works great on its own in warmer climates. But in areas that experience cold temperatures, it may not be a solely reliable system. You could even experience freezing of the system in extreme cold temperatures.

However, if you are only trying to make a hot water system for a camp, or you are living off the grid and can get by with only warm water and not scalding hot sometimes, then a stand along solar system will suffice. It will give you extremely hot water in the hotter/warmer weather, and still provide warmed water in the colder months.

diy standalone heater

Bringing It in

To get the heated water from outside to inside in a standalone water filled system, all you have to do is run the outlet pipe from your system into the house. If you started from scratch, then just plumb it in to your various fixtures as you normally would a hot water line.

If you are introducing it into an existing system, but eliminating a water heater, then you simply tie in to the hot water side of the pipe that previously exited the water heater. To supply the solar water heater, you could plumb the cold water in that previously went into the water heater out to the solar water heater.

This feeds the system with cold water, and returns hot water in the easiest manner. It would be a good idea to insulate any exposed pipes going to and coming from the solar water heating array. If you are using a self-contained water system (off the grid), such as a rainwater collection system, then you can pipe water directly from that storage system into the solar water heating array.

Keep in mind that the higher the water tanks are, the greater your water pressure will be. If you collect rain water off the house, you may want to use a separate water storage tank that is elevated, and you would have to pump water from the rain collecting barrels into your water reservoir tank. Depending on the layout of the land/house, there would be different ways to achieve this.

Recap

Here is a quick recap of your self contained solar hot water system.

  1. Collect rain water or water from other sources
  2. Elevate storage tank to create pressure in the system
  3. Pipe water from storage tank into solar water heating array
  4. Pipe heated water from solar water heating array into the house
  5. Hot water is had by all, everyone smiles

That short list makes it look less daunting, and really it is a very doable project. If you are on a city water system, the only difference is you won’t have an outside water storage tank. You will just pipe directly into the solar water heating array. There are tons of videos on YouTube showing people doing it, and if they can do it then I’m sure you can do it too.

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About Eric W. Eichenberger

Eric W. Eichenberger
Eric Eichenberger is an avid outdoorsman, skilled marksman, and former certified range officer and instructor with nearly 40 years experience handling and repairing firearms. A skilled craftsman with a strong love for working with his hands, Eric spent 20 years as a carpenter and custom woodworker in high end homes. As a gold and silversmith he has created hundreds of pieces of jewelry over the years using the lost wax casting method. The grandson of humble country folk, he was raised with the “do it yourself” mentality and so is accustomed to coming up with unique solutions to problems utilizing materials at hand.

3 comments

  1. can I ask a question,if your so inclined to helping others then why in the hell would a normal hot water heater that costs usually around two to 3 hundred bucks, and with heating element of 28 bucks on ebay which replace 110 ac elements [two total]to convert to 12 volt dc power .including rewired with dc type wire …sence you feel you doing great service helping and saving money for others right well wtf you trying to charge700 to 9oo bucks for one put together already….so this is kinda telling different story you say you are helping others but sir looks no different than any other hyped up web pepper sites, trying to take their hard earned money you say your much more caring and better than rest of these sites,but after seeing your prices im left to believe …its all about the money boys……., and you making more profits on the back of the needy

    • dear sirs
      I can see that it has to be approved before listing as a comment ,….its just a comment that someone could voice opinion is conclusion of what you given to read posted here ,I do like your site and makes good sense and very good info for times to come but your prices [example] hot water heater new is just crazy to high priced, no different than rest or any other survival web sites….that’s all, Mr. Sullivan ….I would be impressed if both comments was accepted and posted here as you with others nicer comments

    • Dan F. Sullivan

      We’re not selling any $700 water heaters. I never had. this article is about making your own, and the heliatos youtube vid was embedded for information purposes. I didn’t have time to see their offers as this is the first time I enter their website. They don’t know us, we don’t know them so please don’t rush to conclusions.

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