homemade solar heaters

Get ready for summer, heat your pool or bathtub with an affordable solar heater
You don't necessarily need a 3000 euro solar heater to heat the water, there are many ways to do it.

We can do it with irrigation tube rolled up inside a hermetic box in the same way as commercial collectors, the only difference is that instead of copper tubes we use rolled plastic tube.

As is the case of the example of ecoinventos ->  http://ecoinventos.com/como-hacer-calentador-solar-casero-piscina/

Although the performance is not comparable with copper tubes, we can take advantage of the economic savings and build several boxes to cushion that loss a little.

And although it seems like a cheap fix, it also works, the plastic takes longer to heat up and transmit the temperature to the water, but being enclosed in the box it is condemned to heat up, and if we circulate the water very slowly or with intermittent pumping Intermittent pumping it will end up by heating up anyway.

Using this method you need to pay more attention to the elements or safety strategies when it comes to overheating, since the plastic can be easily ruined in very high temperatures and if the water has nowhere to escape.

Solar heater with CPVC tubes

CPVC is like PVC but more resistant to heat.
We can use any type of modern tube. Suitable for hot water use.

If our tube is not flexible, we can apply the grid design, which we already know from copper collectors.

There are other important elements when thinking about performance.
It is not just the material of the collector circuit.
We can also improve and improvise with the insulation of the box.
We can also improve with the fluid controlled by an efficient differential thermostat.

On this type of coiled tube collectors, there is a model nicknamed "ensaimada".
It is the same as explained, but with a different design to promote the escape of air and bubbles.

Solar heater with PET bottles

Example project on ecoinventos -> http://ecoinventos.com/calentador-solar-con-botellas-de-gaseosas/

So I started me:

My first personal experiment heating water with the sun in a patio

It has its good side and its bad side, the bad side is usually not explained by anyone, people like the whole thing :-p

The good thing is that it is cheap, it is easy and fast. Above all, cheap.

It heats up quite quickly, it may be because it receives light at 360º as there are no opaque bodies around it.

The bad thing? At dusk or when a cloud hits. The tubes cool down very quickly due to insufficient insulation.

Even worse, their short life, after a short time with the heat, the bottles easily come apart from each other, and the plastic tends to turn whitish.

We must take into account that the bottles must be glued with something that glues and seals and resists the weather and high temperatures, that's what I did, but not even with those.

Is a cheap solar heater convenient?

Well, it depends on the profile of each person.
If you are a beginner and want to rub shoulders with the subject, evaluate it before making a large expense or a large DIY, these methods may be interesting for you.

If you have a roof with easy access, it may be interesting to try it.
I think it is not convenient for someone who does not have much time for experiments or whose only place to put the collector is a place with difficult access.

If you opt for something more serious, today there is good price competition in solar collectors and establishments where they sell us these plates separately.

There are also misconceptions when trying to follow the conventional and what we manufactures the industry.
An example is to use an aluminum box.
This is a very good idea because of its thinness and rigidity. But it is not favorable as an insulator and is not at all economical.
On the other hand, if we use a wooden box, it will be much better as an insulator.
A box with good insulation quality will be very useful for us. from a much more economical collector.

The cover can be made of glass or polycarbonate.
If we find some polycarbonate leftovers in some leftovers in workshops, it will be cheaper.
Polycarbonate is easy to use and light to transport.
Polycarbonate is a much better insulator and more resistant to hail.

Solar heater with vacuum tubes

Heat-pipe vacuum tubes are now very economical and have a much higher performance (you just have to be careful of the excess heat that can burst them).
We do not necessarily have to buy the whole equipment, we just have to adapt it to our project.
There are 2 types of heat pipe vacuum.
One is hermetic and independent whose only content is a glycol that will transmit the heat to the head of each tube.
The other simply contains a U-shaped copper tube where the water circulates inside this tube and is heated by the vacuum tube.

You can perfectly buy the collector and use a old tank or build it yourself, or vice versa.