Make a Solar Water Heater for Under $5

This is amazing. Great use of recycled parts for a truly practical project as well as environmentally friendly. Also, get a nice hot shower out of it :)

This looks a great idea, I might actually give it a go, although my DIY skills are somewhat lacking!

Of course if you rip that grill off the back of a refrigerator then you release all the refrigerent which harms the environment more.

kind of useless unless you use an insulated storage container and a recirculating pump. otherwise you ARE destined to scald yourself.

Adam, if you properly dispose of the Freon or Puron, then this isn't a problem.

Nice post, I'll definitely be giving it a go.

PS You left the P out of Complicated. Irony? :)

Why do you have reflective material on the back of the unit? It seems like it would make the most sense to have black metal. This would absorb more heat and feed it into the piping.

That "Grill" is the condenser coil from a refrigerator, the old ones are copper and the newer ones are aluminum so you won't get one for five dollars. if you want to build this on the cheap then use the old PVC (black) irrigation pipe, lay it out flat and get lots of very hot water.

i use the water heater to heat a large amount of water so i can make a giant outdoor bowl of oat meal! yyuumm

There are flaws in your design. There is a huge waste of the light energy from using that specific refrigerator grill. The portion of the grill which consists of wires strung perpendicularly to the water tubing would not collect as much light energy as a flat black metal panel would. Im sure with this adaptation you would be making boiling water easily if your data is correct.

remember, the key to our energy problems is Efficiency!!!

Wow! Cheap water heater that even helps the Earth? I always wanted to make something like that. Thanks for this article. I will go find the parts to create my own solar thermal water heater for under five dollars!

Buy a 50 gal. drum, paint it black,fill it with water, leave it in the sun - presto, hot water.

Is there any chemical or oil residue in the pipes? It's a great design, and you can easily use more than one coil offset on the same source of water.

you have to use material that will not leach chemicals into the water. Funny pipe for irrigiation with work great, but is it safe?

I'm putting a pergola over my deck and plan to use that 'roof' to install a solar water heater for the non-freeze months. It can look like do-do, and my bitchy neighbors will never see it!

It's a nice proof of concept. Of course it really costs more -- they got the main component for free at the dump -- and it doesn't handle a lot of volume. But it's interesting and shows how simple solar water heating can be.

Can I have instructions on how to make a solar heater?

Just looked at your 5 dollar solar water heater...here is an idea to make it a space heater...from the top line of your water heater run it into the bottom line of the ac condenser...from the ac/condenser top line run back into the bottom of the water heater...it should circulate by itself..if not use a small inline pump to circulate the water...you should prob. use a little antifreeze in the winter..better than water use old motor oil...it holds heat better!

Great idea if I can find another pump this could heat my bag of water I call a swimming pool.

I was thinking that if you actually would want this to work better it only needs a small tweek and would only cost you about 5 more dollars at the auto parts store. The only problem you said you have had is slowing the water down to allow it to heat more. One of the problems I see is you are using siphon power which is not all that great, no control over flow rate. The next problem you have is going from one bucket back to the starting bucket, I think that would be a tremendous amount of heat loss not to mention the time spent monitoring the water level.
Try this, you keep the in and out ports of the thermal pane between 4 and 6 inches above the lowest water line, or the inlet. We also do away with the second catch bucket. In fact if you really want to go high tech get yourself one of those insulated water coolers, they will hold heat in just as good as they do the cold. Plus the spout at the bottom will work great for the inlet line. Now make a trip to the autoparts store and tell them you want two one way fuel line valves. The only thing is make sure they have the arrows marked on them so you know which way to install them. They will cost somewhere near 5 dollars for both, unless you tell them you own a Mercedes then you’ve definitely bumped up the price tag. Next would be to get some line that can hold a little more pressure then a fish tank line. I would suggest about 4 foot of radiator blow-off line, it can hold up to 14 psi and 6 small clamps. The clamps have to be just big enough to get over the line. This will cost approximately another 4 to six dollars for the line and clamps.
Build your thermal collector just as you’ve done except take your new radiator blow-off line and cut it in half, then take about 3 inches off each line. this will give you 2 – three inch pieces and 2 – 21 inch pieces. Take the three inch pieces and attach them to the inlet and out let ports or tubes of your thermal collector, making sure to put on clamps where the hose and the metal tubes meet, but not too tight don’t want to crush the metal tubes and restrict the actual flow capability of the collector. Next you want to install the one way valves, on this part you want one arrow pointing into the collector and the other out or away from the collector. Then after the valves you install the 21 inch lines, you want to make sure you have clamps on both sides of the valves.
At this point you should have your thermal collector and your newly made lines dangling from it. And now for the options, if you went and got a nice thermal jug (igloo), you would connect the inlet line to the water spout at the bottom and lock it open. Open up the breather cap on the top and suck on the return (outlet) line until you get the water past the one way valve that’s pointing away from the thermal collector, and put the outlet line through the breather hole in the top of the igloo. Let the sun do its job. Shortly you should have water hot enough to make some tea with, take caution that the water will be extremely hot.
These one way valves have about a 4 pound stopping ability, thus stopping the water in the collector. So even on cloudy days or nominal weather the water would take as long as it needs to heat up. As the water heats up the pressure or psi will increase. When the pressure reaches 4 plus pounds it will expel itself out of the collector and automatically suck in cooler water behind it. Cooler water means less psi and the valves will automatically close to start the whole cycle over again. This will create a continuous cycle of flowing water and again with a word of caution there is no temperature control switch. Since the inlet line will be towards the bottom of the igloo and we already know about convection, the cooler water needing to be heated will be first in line. The only real problem left is to play with the height of the tank in relation to the thermal collector, this is due to the fact that you don’t want the water weight to force the water through, and this is dependant on the size of your container. Thus relieving you from having to monitor the water and being on tap whenever you need it. The only extra note is that you will from time to time want to visually check your thermal collector to make sure no leaks have been made from the pressure created during the process.
This setup I think will better suit most folks and for the price of the extra bucket you were using trade it for the valves and blow-off line. I will say though nice work on recycling materials for the thermal collector. Hope to see more in the future.

The idea the same as mine,I am afraid that this kind of collector insulation ineffective.I think if in the copper tube covered with a layer of asphalt below will be even better.Preferably a temperature increase circulation pump.

http://www.cnsolarwaterheater.com
http://www.prcsolar.com

I am making a solar panel with 3 refrigerator coil sets in in it to put on the roof of my garage, so I am looking for an electric inline circulating pump. It should move the water very slowly for sure. Any product suggestions out there?

If you put your heat collection coil lower than your tank, you shouldn't have a need for additional electricity consuming circulating pumps. It might be a little harder to keep things looking like an eye sore, but you wouldn't be defeating your energy saving purpose by adding a pump. The trick is finding the right heat collection coil size / storage tank size ratio... If you build the coil in small sections, you can keep adding sections until you get the desired average water temperature. Or if you live in an area that has varying climates, rig up several sections on a trunk line with individual shutoff valves for each section. That would allow you to adjust your heat collector size to fit the needs of your season.

Is it possible to connect the water heating unit to the cold water line entering into your home water heater to get a preheat condition. How would the water circulate to keep the temperature in the tank elevated? Without that the water would likely flow through the solar heater so fast when being used inside the home to have no beneficial effect.

Quoting: "the water exiting the return pipe is about 110 degrees"

Well, water boils at 100 degrees, but 90 degrees is a right angle.

To get a cold water feed you would need a header tank with a ball-cock type valve to keep the water level up in the heating loop. This is just like a normal hot water storgage tank and boiler setup in a regular house.

110F is temperature coming out of pipe. Water boils at 100C (212F).

You need to be able to tie into the existing water system in your home. The panel also needs to be pressurized. I would suggest a professional installation if you want to save real money and have it look decent. With current solar rebates the payback time could be as little as 2 years in some cities.