Homemade solar water heater
Homemade solar water heater
DIY Solar water heater
I present my homemade solar water heater, how to build a water heater capable of supplying hot water to 4 people each day, with a very low cost without subsidies.
If you can understand the project in my homemade solar water heater, you will be able to build and maintain your solar heater without help and without maintenance and without paying a high cost for a breakdown.
If your home solar water heater will be forced circulation, I recommend that you use a small centrifugal pump that is economical and powerful, possibly non-submersible. I can offer you a bomb and perfect fit for this project.
Here you can get-> Solar centrifugal powerful and cheap
The purpose of this project home solar water heater, is to understand how the resources of a homemade solar water heater, which are as efficient and already exploited commercially for some time, explain briefly why it works, and how to do at home as a resource advantage so good and so free as the sun, and how to make it ourselves at home slowly and comfortably, DIY learning, and without having to pay such a high price but the performance is a little lower than we offering the industrial prototype, even though you may get a performance equal or superior to some of them, because I have seen on some websites that some manufacturers use poor quality materials.
First we have to understand he does, and how does a solar collector for heating large water capacity as high temperature and in a short time, because that is, in very warm water very quickly.
Any homemade solar water heater, or you can buy commercial, seeking the same function, accumulate much heat inside a box (collector), and when said housing is hot flowing inside this box the water in our tank, the while the water passes through the housing and be heated (and returns to the reservoir already heated), the cooling will inevitably box and when the box is already little cold or hot water that flow dentendremos waiting to be much to hot to repeat the above operation, until the box and stop warming (because it was the sun), with this we get heat water in our tank at the highest temperature possible.
All solar heaters, commercial and home, consisting of 3 parts to achieve the above described:
1 – The collector: The most important element, which heats the heat transfer fluid or water itself.
2 – The ‘engine’: That may be a pump that moves water flow at appropriate times and in a strategic way (this is called forced circulation system), or we can do without this ‘engine’ if we mount the collector and deposit in the appropriate way to handle physics automatically move this flow (known as natural circulation)
3 – The deposit: Element not least, must be properly assembled and prepared, and properly insulated. A poorly insulated tank will ruin all our assembly and will cause very little hot water and cool our rapidly.
The efficiency of our home solar water heater will depend on the materials used in the collector and isolation, and isolation of the water tank, there are very few secrets that leverage bit more performance, but we can do it almost 100% in house and perfectly comparable yields
The collector is usually a metal tube normally travel, it is also possible to use heat-resistant plastics such as CPVC or polyethylene plastic but the system is much less efficient, some websites claim that with these plastic is cheaper, but it is a dubious argument, and we must do a coil much longer and complex, using many more pipes and joints to compensate for this loss of performance, we will come out more profitable use copper and brass, and less work, for an easy and simple , instead of a mounting with many polyethylene pipe with their respective junction elements
The tubing material mentioned that better performance will give us will be copper or aluminum, stainless steel could even be useful though less yield and potential problems with long-term oxidation.
The engine, if we choose a water pump assembly will be a little more complicated, but if we do it well worthwhile and worth much less wasted that the direct and indirect solar radiation .. But it all depends on who governs this water pump, water pump can be activated and deactivated in the following ways :
-> Timer : this is usually not a good idea because a timer never know when it’s sunny or raining, and neither is the same 14h in August than in January, unnecessary movement cycles occur even counterproductive, and we would be losing heat, punishing and water pump overheating.
-> Powered by a solar panel : pump is activated when there is some solar activity, The problem is that the solar panel would put the pump at the same time you get sun, and the collector needs its time to warm up. Also happen that when you flip up the sun or the solar panel would stop the pump immediately, and the collector will probably give much heat.
Does this mean, that never is directly proportional to the presence of the sun accumulated temperature in the collector, but it would be a more or less logical, is not the best idea but it is preferable to blind management offered a timer
-> Ruled by a differential thermostat : It is not ideal, is an electronic device that is plugged into the mains, gives the connections for 2 sensors for temperature and electrical connection of the pump.
The function of this differential thermostat, pump is activated when the sensor detects that the collector temperature is no greater than the tank sensor, and disconnect the pump stops when this happen.
I must clarify that we are talking about a small water pump and Sencillito preferable typical submersible pumps aquarium, small, because we need a slow water circulation, not too slow, but slow for the water Wander around the collector and hot for ‘the ride’, if the pump circulates the water very slightly not give you time to warm up in the collector, and also we will be spending many watts for something that is not working well.
The power consumption of the entire system (set of differential thermostat and water pump) is usually very low, between 5w to 20w depending on the pump, if it is managed by the consumption differential thermostat is in short cycles discontinuous to worn throughout the day we will change very little electricity had been heated to 100 or 200 liters of water.
No motor, known as thermosiphon deposit is achieved by placing the manifold and above and measures distances respecting specific physical occurs that causes the hot water (weighing less) to flow upward and cold water (heavier) immerse down, this automatic mechanism of the nature and form of thermosyphon mount make the hottest water always go into the tank, and instead of the water tank less hot journey to the collector, you will find this information very detailed in many Websites included in wikipedia.
I have chosen to do with water pump (forced circulation) and I will base the whole project in that mode (but you can follow the same instructions omitting the part that your discards)
For two simple reasons:
- 1, gives a lot of freedom to locate where we come better collector and the tank, but always should be as close to each other to prevent heat loss in water courses, and in our case we will put close to use a water pump cheap and underpowered.
- 2, because the yield is much higher.
I will post a clear and practical brief case to understand because it is more efficient than forced circulation thermosiphon system:
Thermosyphon circulation thermosyphon system is done automatically and without any possibility of control, begins to run when a certain temperature difference and in a very slow, is free but slow engine, imagine that our water is heating collector in our fall weather, and just as hot water will raise the deposit for this effect is a large cloud thermosyphon and untimely, and this water cools almost ready, or not doing enough sun to thermosyphon facilitate this process, no warm up and no water.
This does not mean that it is not very efficient, I make such comments because I am comparing with forced circulation, but also efficient thermosiphon because it works and it is still free.
Forced circulation :
If I have forced circulation forced circulation system, I decide and set up on my thermostat from that exchange temperature difference and water collector tank, then a fall weather I can foresee me rather low temperatures, and I can configure differential thermostat to collect water from the collector even with only one degree more than the deposit, would be like the soil that collects hair a hairdresser to get a wig, hot can not my water at a desirable temperature in only 1 day But if I keep and isolated warm water well that maybe the second day and the temperature approaching that desire, And the third hotter than I expected, so a little heated but warm water also saves a lot of energy, because if I heat this warm water with an electrical resistance or I pass a gas heater, need less time and less energy than a cold. This is the logical and the usual, have a second power source as reinforcement for cold days, warm water to make a nice hot water and providing low energy
Drawbacks forced circulation: The cost, the thermostat with 2 sensors will cost between 40 € and 60 €, and a submersible pump for aquarium from 10 to 20 €, or ideally a pump submersible water 12Litros/minuto can cost us about 30 € to 40 €.
It depends entirely on the power to the house (unless you work it the thermostat and pump with a solar panel and battery).
Advantages of forced circulation: It cost less than 100 € is justified by its early amortization, for the rest that provides water pump at times it is unnecessary to pump for circulation, and is a way to make the most of high temperatures and the possibility of taking advantage of lower temperatures.
The thermostat control at all times and offers the possibility of managing and configuring a possible electrical resistance, the information you provide us (tank temperature and collector)
Business models are almost all dedicated to thermosyphon system, it is conceivable that the reason for this preference by most manufacturers, is due to the simplicity and minimize maintenance and breakdowns.
But in our case it assemble ourselves and cost price of material whether it is worth, in the worst case we may be Averie ever water pump, which will replace any other pump 2nd hand or by some 20 or 30 € if new.
I’m sure even if you had to change the pump every year, spending would be amortized by the time that this pump makes it possible to heat the water when other thermosyphon solar systems can not.
There are many more variations on solar heaters with heat exchangers, heat transfer with glycols with various devices, both sophistication lose performance, and the subject of glycols benefit only very cold climates, but if you live in extremely cold climates may follow any simplified model, like mine for example.
If you’re interested in my assembly, press the menu tabs, and I’ll explain step by step each part of the system.