How to make solar water heating. solar water heater

Every year, traditional energy sources are becoming more expensive, and there is no end in sight to this price race. Meanwhile, the most powerful source of energy, which we see almost every day, "works" for free. And if humanity has not yet learned how to effectively receive energy directly in the form of electricity, then any person can use the thermal energy of the sun - there would be a desire!

Indeed, in a sunny area, the luminary sends approximately 1 kW of energy every hour. It is a sin not to use such a source at least for heating water. At the same time, the cost of creating and installing a water heating device is minimal. Inventors in the vastness of the country have long been using a variety of installations for heating water.

Among them are the simplest and more complex, with automatic control. It all depends on technical readiness, financial capabilities and, of course, desire.

How do craftsmen get hot water from the sun today?

Creating a solar heater with your own hands is not difficult at all.

This is the easiest option.
The usual container in the form of a barrel, an old tank, is installed on the roof of a summer shower or a house, a barn and connected through a hose to an ordinary tap.

If the container turns black, heating will occur faster.

By the end of the day, the water warms up to about 45C. These data are valid for a polyethylene tank of 200-300 liters. It is desirable that it be flat - this increases the heating efficiency.

The whole disadvantage is that all the water must be used in the evening, because. it will be cold in the morning.

To “eliminate” this drawback, you will have to insulate the tank itself or drain the heated water into an insulated tank again. You can simply feed the water into the boiler and, when it cools down, heat it up. At least some electricity, but it is saved.

Another option is to keep the boiler permanently connected to a roof-mounted tank. Then the water will constantly circulate; it can be used online.

A significant drawback of the system is that it does not work at temperatures below +20C. Therefore, there are other ways to heat water in the off-season.

Solar water heater - collector

Such a device is considered the most effective. It's all about the material from which the collector is made. Most often it is:

• steel
• brass.

But assembly using metal is laborious (soldering, welding, sealing, etc.), so other materials are used. There is an option to use polypropylene pipes - they are cheaper. However, their connection can also cause difficulties associated with sealing joints.

Another disadvantage is a significant deformation during heating, this is not so noticeable for metal-plastic pipes, but polypropylene has a high coefficient of thermal expansion. This deficiency can cause leaks in the system.

There is an original and simple solution, which is to use a garden hose as a solar collector. The whole assembly process is limited to twisting it into a spiral and placing it in a suitable box.

Excellent flexibility, no connections guarantee no leakage, and the length of the hose allows it to be connected directly to plumbing fixtures without intermediate connections.

The performance of such a system depends on the length of the hose. With a diameter of 2.5 cm and an air temperature of at least +25C, one meter of the hose heats 3.5 liters of water up to +45C.

It turns out that on a sunny day by the evening 10 meters will "give" you 280 liters of hot water. The system works when the temperature drops to +8C.

How is the process of heating water

The sun's rays fall on the spiral through the glass and heat the spiral. The heated water becomes a source of long-wave radiation, which is reflected from the glass. That is, the sun's rays are in a kind of thermal "trap".

1. To create this heating device, you will need a box where a black hose coil will be placed, using other shades will result in a loss of 5% of heat. It can be rubber or PVC. Diameter - not less than 1.9 cm, wall thickness not more than 2.5 mm.
2. The hose will connect to the boiler, which should be above the spiral. The bottom of the box must be insulated with foam, painted black.
3. The box itself is closed on top with window glass (organic glass is not suitable due to the fact that it does not retain solar radiation well).
4. A rubber gasket must be installed between the glass and the box.

Water heater from PET bottles

The idea is to first create modules (3 bottles each, you can also 4, 5), then connect each of them to a plastic pipe, which is connected on one side to a source of cold water, on the other hand, it gives out hot liquid. It is best to use bottles with a capacity of 2-2.5 liters. It is necessary to connect them according to the principle "neck to the bottom".

• To do this, a hole is cut in the bottom for the neck with a diameter of 26 mm. The hole must be located strictly in the center. Therefore, first mark the center by drilling a hole with a 3-6 mm drill.
• To ensure sealing, lubricate the threads on the neck with sealant and leave the structure stationary for 2-3 days. Poke a hole in the bottom of the top bottle!
• A module of three bottles in the same way (you can think of some other) is attached to a plastic pipe, at one end of which cold water enters.

The number of modules can be large. To get 200 liters of hot water, you need about 110 bottles - this is three square meters of area.

• Place the resulting block in a box covered with window glass. The angle of inclination is from 10 to 30 degrees.

The resulting system is much more efficient than a black water barrel mounted on the roof.

Most home-made designs for heating water by the sun in summer save 70-80% of the energy spent on heating. In autumn, spring - up to 40%. At the same time, up to 400 kW / h per person is “taken” from the luminary in a year! There is something to think about.

The level of development of modern technologies and materials is so high that not using solar energy is unreasonable from the financial side and criminal in relation to the environment. Unfortunately, the purchase of industrial installations for generating electricity and heat is irrational due to their high cost. Nevertheless, there is a way out: to make a productive solar collector with your own hands from materials that can be found in the nearest hardware store.

The purpose of the solar collector, its advantages and disadvantages

A solar water heater (liquid solar collector) is a device that heats a coolant with the help of solar energy. It is used for space heating, hot water supply, water heating in swimming pools, etc.

The solar collector will provide the house with hot water and heat

The prerequisite for using an eco-friendly water heater is the fact that solar radiation falls on the Earth all year round, although it differs in intensity in winter and summer. So, for middle latitudes, the daily amount of energy in the cold season reaches 1–3 kWh per 1 sq.m, while in the period from March to October this value varies from 4 to 8 kWh/m 2. If we talk about the southern regions, then the figures can be safely increased by 20-40%.

As you can see, the efficiency of the installation depends on the region, but even in the north of our country, the solar collector will provide the need for hot water - the main thing is that there are fewer clouds in the sky. If we talk about the middle lane and the southern regions, then a solar-powered installation will be able to replace the boiler and cover the needs of the heating system coolant in winter. Of course, we are talking about productive water heaters of several tens of square meters.

A solar battery will help save money from the family budget. The following material will help to make it yourself:

Table: distribution of solar energy by region

Home-built solar collectors are no match for factory-made solar collectors, but a home-made solar installation will cut domestic water heating costs and save electricity when connected to a washing machine and dishwasher.

Advantages of solar water heaters:

• relatively simple design;
• high reliability;
• efficient operation regardless of the season;
• long service life;
• the possibility of saving gas and electricity;
• no permission is required to install equipment;
• small mass;
• ease of installation;
• complete autonomy.

As for the negative points, not a single installation for obtaining alternative energy can do without them. In our case, the disadvantages are:

• high cost of factory equipment;
• dependence of the solar collector efficiency on the time of year and geographic latitude;
• susceptibility to hail;
• additional costs for the installation of a heat storage tank;
• dependence of the energy efficiency of the instrument on cloudiness.

Considering the pros and cons of solar water heaters, one should not forget about the environmental side of the issue - such installations are safe for humans and do not harm our planet.

The factory solar collector resembles a construction set, with which you can quickly assemble the installation of the required performance

Types of solar water heaters: the choice of design for self-production

Depending on the temperature that solar heaters develop, there are:

• low-temperature devices - designed for heating liquids up to 50 ° C;
• medium temperature solar collectors - increase the outlet water temperature up to 80 °C;
• high-temperature installations - heat the coolant to the boiling point.

At home, you can build a solar water heater of the first or second type. To manufacture a high-temperature collector, industrial equipment, new technologies and expensive materials will be needed.

By design, all liquid solar collectors are divided into three types:

• flat water heaters;
• vacuum thermosyphon devices;
• solar concentrators.

A flat solar collector is a low heat-insulated box. A light-absorbing plate and a tubular circuit are installed inside. The absorbing panel (absorber) has an increased thermal conductivity. Due to this, it is possible to achieve maximum energy transfer to the coolant circulating around the water heater circuit. The simplicity and efficiency of flat installations is reflected in numerous designs developed by craftsmen.

Inside a flat solar collector - a light-absorbing plate and a tubular circuit

The principle of operation of vacuum solar water heaters is based on the thermos effect. The design is based on dozens of double glass flasks. The outer tube is made of impact-resistant, tempered glass that resists hail and wind. The inner tube has a special coating to increase light absorption. Air is evacuated from the space between the elements of the flask, which makes it possible to avoid heat losses. In the center of the structure there is a copper thermal circuit filled with low-boiling coolant (freon) - it is the heater of the vacuum solar collector. In the process, the process fluid evaporates and transfers heat energy to the main circuit working fluid. In this capacity, antifreeze is most often used. This design allows the system to operate at temperatures down to -50 °C. It is difficult to build such an installation at home, so there are a few self-made vacuum-type structures.

The design of the vacuum solar collector is based on a set of double glass flasks

The solar concentrator is based on a spherical mirror capable of focusing solar radiation to a point. The liquid is heated in a spiral metal circuit, which is placed at the focus of the installation. The advantage of solar concentrators is the ability to develop high temperatures, but the need for a tracking system for the Sun reduces their popularity among DIYers.

Building a productive solar concentrator at home is not an easy task

For home fabrication, flat plate solar heaters built using thermal insulation materials, high transmittance glass and copper absorbers are best suited.

The device and principle of operation of a flat solar collector

A homemade solar water heater consists of a flat wooden frame (box) with a blank back wall. At the bottom is the main element of the device - the absorber. Most often it is made of a metal sheet attached to a tubular collector. The efficiency of energy transfer depends on the contact of the absorber plate with the heat exchanger pipes, so these parts are welded or soldered with a continuous seam.

The fluid circuit itself is an array of vertically mounted tubes. In the upper and lower parts, they are connected to horizontal pipes of increased diameter, which are intended for the supply and withdrawal of the coolant. The inlet and outlet for the liquid are located diagonally - due to this, complete heat removal from the heat exchanger elements is ensured. Antifreeze for heating systems or other antifreeze solutions are used as a heat carrier.

The absorber is covered with light-absorbing paint, glass is placed on top, and the box is protected with a layer of thermal insulation. To simplify the task, the glazing area is divided into parts, and in order to increase productivity, double-glazed windows are used. The closed design creates the effect of a thermos in the solar collector and at the same time prevents heat loss due to wind, rain and other external factors.

The solar water heater works like this:

1. The non-freezing liquid heated in the solar collector rises through the tubes and enters the heat storage tank through the coolant withdrawal branch.
2. Moving through the heat exchanger installed inside the storage tank, the antifreeze gives off heat to the water.
3. The cooled working fluid enters the lower part of the solar water heater circuit.
4. The water heated in the tank rises and is taken for the needs of hot water supply. The replenishment of the liquid in the heat storage tank occurs due to the water pipe connected to the bottom. If the solar collector works as a heating system heater, then a circulation pump is used to circulate water in a closed secondary circuit.

The constant movement of the coolant and the presence of a heat accumulator allows you to accumulate energy while the sun is shining, and gradually spend it even when the luminary is hiding behind the horizon.

The scheme for connecting a solar collector to a storage tank is not so complicated.

Options for homemade solar installations

A feature of do-it-yourself solar water heaters is that almost all devices have the same design of a heat-insulated box. Often the frame is assembled from lumber and covered with mineral wool and a heat-reflecting film. As for the absorber, metal and plastic pipes are used for its production, as well as ready-made components from unnecessary household equipment.

From a garden hose

A snail-shaped garden hose or PVC plumbing pipe has a large surface area, which makes it possible to use such a circuit as a water heater for the needs of an outdoor shower, kitchen or pool heating. Of course, for these purposes it is better to take black materials and be sure to use a storage tank, otherwise the absorber will overheat during the peak of the summer heat.

A flat-plate garden hose collector is the easiest way to heat your pool water

From the condenser of an old refrigerator

The external heat exchanger of a used refrigerator or freezer is a ready-made solar collector absorber. All that remains to be done is to retrofit it with a heat-absorbing sheet and install it in the case. Of course, the performance of such a system will be small, but in the warm season, a water heater made from refrigeration equipment parts will cover the hot water needs of a small country house or cottage.

The heat exchanger of an old refrigerator is an almost ready-made absorber for a small solar heater

From a flat radiator heating system

The manufacture of a solar collector from a steel radiator does not even require the installation of an absorbing plate. It is enough to cover the device with black heat-resistant paint and mount it in a sealed casing. The performance of one installation is more than enough for a hot water supply system. If you make several water heaters, you can save on heating the house in cold sunny weather. By the way, a solar plant assembled from radiators will heat utility rooms, a garage or a greenhouse.

The steel radiator of the heating system will serve as the basis for the construction of an environmentally friendly water heater

From polypropylene or polyethylene pipes

Pipes made of metal-plastic, polyethylene and polypropylene, as well as fittings and devices for their installation, allow you to build solar circuits of any size and configuration. Such installations have good performance and are used for space heating and hot water for household needs (kitchen, bathroom, etc.).

The advantage of a solar collector made of plastic pipes is low cost and ease of installation

From copper pipes

Absorbers constructed from copper plates and tubes have the highest heat transfer, therefore they are successfully used for heating the coolant of heating systems and in hot water supply. The disadvantages of copper collectors include high labor costs and the cost of materials.

The use of copper pipes and plates for the manufacture of the absorber guarantees a high efficiency of the solar plant

Solar collector calculation method

The performance of a solar solar collector is calculated based on the fact that 1 sq.m of installation on a clear day accounts for from 800 to 1 thousand W of thermal energy. The losses of this heat on the reverse side and walls of the structure are calculated according to the thermal insulation coefficient of the insulation used. If expanded polystyrene is used, then for it the heat loss coefficient is 0.05 W / m × ° C. With a material thickness of 10 cm and a temperature difference of 50 °C inside and outside the structure, the heat loss is 0.05/0.1 × 50 = 25 W. Taking into account the side walls and pipes, this value is doubled. Thus, the total amount of outgoing energy will be 50 W per 1 sq.m of solar heater surface.

To heat 1 liter of water by one degree, 1.16 W of thermal energy is required, therefore, for our model of a solar collector with an area of ​​1 sq.m and a temperature difference of 50 °C, it will be possible to obtain a conditional performance coefficient of 800/1.16 = 689.65/kg × ° C. This value shows that a 1 sq.m installation will heat up 20 liters of water by 35 °C within an hour.

The calculation of the required performance of a solar water heater is carried out according to the formula W = Q × V × δT, where Q is the heat capacity of water (1.16 W/kg × °C); V - volume, l; δT is the temperature difference at the inlet and outlet of the installation.

Statistics say that one adult needs 50 liters of hot water per day. On average, for hot water supply, it is enough to raise the water temperature by 40 °C, which, when calculated using this formula, requires energy costs W = 1.16 × 50 × 40 = 2.3 kW. To find out the area of ​​the solar collector, this value must be divided by the amount of solar energy per 1 sq.m of surface at a given geographical latitude.

Calculation of required solar system parameters

Making solar water heater with copper absorber

The solar collector proposed for production on a sunny winter day heats water to a temperature above 90 ° C, and in cloudy weather - up to 40 ° C. This is enough to provide the house with hot water. If you want to heat your home with solar energy, you will need several such installations.

Required materials and tools

To make a water heater you will need:

• sheet copper with a thickness of at least 0.2 mm and dimensions of 0.98 × 2 m;
• copper tube Ø10 mm, length 20 m;
• copper tube Ø22 mm, length 2.5 m;
• thread 3/4˝ - 2 pcs;
• plug 3/4˝ - 2 pcs;
• soft solder SANHA or POS-40 - 0.5 kg;
• flux;
• chemicals for absorber blackening;
• OSB board 10 mm thick;
• furniture corners - 32 pieces;
• basalt wool 50 mm thick;
• sheet heat-reflecting insulation 20 mm thick;
• rail 20x30 - 10m;
• door or window seal - 6 m;
• window glass 4 mm thick or double-glazed window 0.98x2.01 m;
• self-tapping screws;
• dye.

In addition, prepare the following tools:

• electric drill;
• a set of drills for metal;
• "crown" or cutter for woodworking Ø20 mm;
• pipe cutter;
• gas-burner;
• respirator;
• paint brush;
• a set of screwdrivers or a screwdriver;
• electric jigsaw.

To pressurize the circuit, you will also need a compressor and a pressure gauge designed for pressure up to 10 atmospheres.

For soft soldering, a simple gas torch is suitable

Instructions for the progress of work

1. Using a pipe cutter, the copper tube is cut into pieces. You will get 2 parts Ø22 mm 1.25 m long and 10 elements Ø10 mm 2 m long.
2. In thick pipes, a margin of 150 mm is made from the edge and 10 holes Ø10 mm are made every 100 mm.
3. Thin tubes are inserted into the resulting holes so that they protrude inward by no more than 1–2 mm. Otherwise, excessive hydraulic resistance will appear in the radiator.
4. Using a gas burner, hot air gun and solder, all parts of the radiator are interconnected.

   

   The solar collector circuit works under pressure, so special attention is paid to the tightness of the connections

   To assemble the radiator, you can use special fittings, but in this case, the cost of the solar system will increase significantly. In addition, collapsible connections do not guarantee the tightness of the structure under variable thermodynamic loads.

5. Plugs and threads are soldered in pairs along the radiator diagonals to 3/4˝ pipes.
6. Having closed the outlet thread with a plug, a fitting is screwed onto the inlet of the assembled manifold and the compressor is connected.

   

   The compressor is connected with a fitting

7. The radiator is placed in a container with water and a pressure of 7–8 atm is pumped up by the compressor. The bubbles rising at the joints are used to judge the tightness of the soldered joints.
   

   If a suitable container for checking the collector could not be found, then you can assemble it yourself. For this, a box or a simple barrier is made from improvised means (trimming of lumber, brick, etc.) and covered with plastic wrap.

8. After checking the tightness, the radiator is dried and degreased. Then proceed to the soldering of the copper sheet. Solder the absorber sheet to the tubes with a continuous seam along the entire length of each element of the copper circuit.

   

   Soldering of the absorber sheet is carried out with a continuous seam

9. Since the solar collector absorber is made of copper, chemical blackening can be used instead of painting. This will allow you to get a real selective coating on the surface, similar to what is obtained in the factory. To do this, a heated chemical solution is poured into the container for leak testing and the absorber is placed face down. During the reaction, the temperature of the reagents is maintained by any available method (for example, by constantly pumping the solution through a vessel with a boiler).

   

   Blackening of copper is one of the most critical stages in the manufacture of an absorber.

   As a liquid for chemical blackening, you can use a solution of sodium hydroxide (60 g) and potassium persulfate or ammonium persulfate (16 g) in water (1 l). Remember that these substances are dangerous to humans, and the process of copper oxidation itself is associated with the release of harmful gases. Therefore, it is imperative to use protective equipment - a respirator, goggles and rubber gloves, and the work itself is best done outdoors or in a well-ventilated area.

10. Parts are cut out from the OSB sheet for assembling the solar collector housing - the bottom 1x2 m, the sides 0.16x2 m, the top 0.18x1 m and the bottom 0.17x1 m panels, as well as 2 supporting partitions 0.13x0.98 m.
11. A 20x30 mm rail is cut into pieces: 1.94 m - 4 pcs. and 0.98 m - 2 pcs.
12. Holes Ø20 mm are made in the side walls for the inlet and outlet pipes, and 3-4 holes Ø8 mm are drilled in the lower part of the collector for microventilation.

    

    Holes needed for micro-ventilation

13. Cutouts are made in the partitions for the absorber tubes.
14. A support frame is assembled from slats 20x30 mm.
15. Using furniture corners and self-tapping screws, the frame is sheathed with OSB panels. In this case, the side walls should rest on the bottom - this will prevent the deflection of the body. The bottom panel is lowered 10 mm from the rest to cover it with glass. This will prevent precipitation from getting inside the frame.
16. Install interior partitions.

    

    When assembling the case, be sure to use a building square, otherwise the design may turn out to be lopsided

17. The bottom and sides of the body are insulated with mineral wool and covered with rolled heat-reflecting material.

    

    It is better to use mineral wool with moisture-repellent impregnation.

18. The absorber is placed on the prepared space. To do this, one of the side panels is dismantled, which is then put in place.

    

    Scheme of the internal "pie" of the solar collector

19. At a distance of 1 cm from the upper edge of the box, the inner perimeter of the structure is sheathed with a wooden lath 20x30 mm so that its wide side touches the walls.
20. A sealing gum is glued around the perimeter.

    

    For tightness, use a conventional window seal.

21. Glass or a double-glazed window is laid, the contour of which is also pasted over with a window seal.
22. The structure is pressed with an aluminum corner, in which holes for self-tapping screws are pre-drilled. At this stage, the collector assembly is considered complete.

    

    When assembled, the thickness of the solar collector is about 17 cm

To prevent moisture ingress and heat leakage, at all stages the joints and mating points of the parts are treated with silicone sealant. To protect the structure from precipitation, the wood is coated with a special compound and painted with enamel.

Features of installation and operation of liquid heating collectors

To place the solar collector, choose a spacious place that is not shaded all daylight hours. The mounting bracket or subframe is made of wooden slats or metal in such a way that the inclination of the water heater is adjustable from 45 to 60 degrees from the vertical axis.

Connection diagram for a solar heater in a forced circulation system

The storage tank to reduce heat losses is placed as close as possible to the installation. Depending on the conditions, natural or forced circulation of the coolant is organized. In the latter case, a controller is used with a temperature sensor embedded in the outlet pipe. The pumping of the working fluid along the circuit will turn on when its temperature reaches the programmed value.

A seasonally operating system is filled with water, while year-round use of a solar water heater requires the use of an antifreeze fluid. The ideal option is a special antifreeze for solar systems, but liquids intended for car radiators or domestic heating systems are also used to save money.

Video: do-it-yourself solar water heater

Building a solar collector is not only an interesting and exciting activity. A solar water heater will save your family budget and will prove that you can protect the environment not only in words, but also in real deeds.

Thanks to my versatile hobbies, I write on various topics, but my favorite ones are engineering, technology and construction. Perhaps because I know a lot of nuances in these areas, not only theoretically, as a result of studying at a technical university and graduate school, but also from the practical side, since I try to do everything with my own hands.

In this article we will talk about such an invention of mankind as a solar water heater, make it with our own hands, learn how to use it. But first, let's talk about why this device is relevant in our time.

Many owners of dachas and cottages would like to have not only a shower with hot water. Human life is generally impossible to imagine without such convenience as hot water. Lucky are those who have a gas pipeline route near their home and have the opportunity to bring gas into the house, as well as those whose house is connected to the central hot water supply.

But what if you live in a village and you have neither gas nor central heating? Would a primitive barrel on the roof of a shower cubicle frame in the yard help? Of course, boiler houses are being built in large villages. But this is not always beneficial for the common man. The fuel it consumes is quite expensive. Consequently, the payment for hot water will not be cheap.

In modern life there are no dead ends, there is always a way out. You can have hot water not only in hot summer. Cloudy autumn, cool spring will also give their heat to solar heaters. And you don't have to pay extra for it. After reading the step-by-step instructions on how to make a solar water heater with your own hands and purchasing the necessary materials, you can easily make this device.

Varieties of heaters

To begin with, let's figure out what types of water heaters are, which will help to understand what their efficiency depends on.

Systems for heating water by the sun are globally divided into two types - storage and flow. But, if we consider in more detail, we can note:

• Stationary water heaters. In this system, there is a cyclic (periodic) make-up of water.
• solar heater that water circulation occurs naturally. The rays of the sun pass through the collector. The sun gives off its life-giving warmth. Thermal energy heats water.
  The so-called thermosyphon effect. Cold water is pushed out by hot water and moves naturally to the place of heating. In this design, a pump is not required at all.
• Solar heater, which design connected pump. Due to the operation of the pump, the circulation of water in this system is forced.

Depending on the situation and available materials, you can make a solar water heater of the desired design.

Design and principle of operation

Solar water heater, using the principle of "greenhouse effect" - the design is quite simple. An avankamera, two collectors, a drive - that's the whole heater circuit. Some of the elements of the solar heater are purchased in specialized stores, but can be found in scrap metal.

The accumulator is most often a steel barrel with a volume of 200 liters. The thermal insulation of the barrel will help keep the water warm for a long time. Therefore, place the barrel in a wooden box, and in the empty gaps that remain on the sides, it is necessary to lay heat-insulating material.

Step-by-step instructions for creating a water heater

So, it's time to describe step by step how to make a solar water heater with your own hands:

1. First you need to drill a hole in the bottom side.
2. Next, install the outlet pipe.
3. A shut-off valve must be screwed onto this branch pipe. Additionally, you can mount a nozzle in the form of a shower.
4. Then you need to cut a hole in the top side of the tank.
5. Calculate and make a lid to size, which can be of any design, the main thing is that debris does not get into the water.
6. Outside, the tank is painted with dark paint so that the heat stays inside longer.
7. Next, the tank must be connected to the water supply for supplying cold water, which may require additional holes in the tank. There should also be a pipe from the tank that returns the heated water. There must be constipation everywhere.

The principle of operation of such a water heater is simple: open the valve, the tank is filled, then close the valve.

We make a collector with our own hands

The collector is a tubular radiator, which is assembled from steel pipes. To create such a device, you need the following materials:

• sealant;
• Sheets of copper;
• Copper or steel tube;
• Large pipes;
• Insulation in rolls;
• Glass (window is suitable);
• Corner;
• Plugs, screws, fittings, dowels;
• Dark and white paint.

It is usually enclosed in a wooden box, and on the one hand this box is made of glass. Thermal insulation is laid on its bottom, and a galvanized metal sheet is attached on top. It and the collector pipes are painted black, but the outer sides, on the contrary, need to be painted white, which will avoid heat loss (heat radiation).

Do-it-yourself solar water heater scheme for the pool and home

It is reasonable to place a water heating manifold on the roof of a barn or house, preferably on its south side. The recommended angle is 30-40 degrees relative to the horizon. In this installation, the "captured" thermal energy is stored for quite a long time (accumulated).

Creation of an avankamera

The fore-chamber serves to create excess pressure in the hydraulic system (within 80-100 cm of water column). It is made from a suitable vessel, for example, from a milk can (40 l.). The feeding device makes it possible for the fore-chamber to operate in automatic mode. Here, an ordinary float valve has found its application, which is widely used in drain tanks.

The antechamber is installed so that the water level in the reservoir is 0.8-1 m less than in it. Before installing a van chamber and a drive in the attic, be sure to make sure that the ceilings are strong, because the mass of water can be quite large.

Such a solar water heater system is quite efficient, and the efficiency is very high.

Video instructions

If you managed to visit the southern countries, then, for sure, you often noticed structures standing on the roofs of houses. The guides explained that these are solar panels for heating water and heating the home. Both abroad and in our country, the progressive population stands up for alternative energy sources. A solar-powered water heater is one such successful invention that is able to fully function even in winter.

The sun is a very powerful and, most importantly, an endless source of heat energy. No one takes money for its use, and therefore it is worth considering how to use such an advantage for your own good. Factory taxes on solar water heaters can cost a lot. If you understand the principle of operation of such a device, then you can do something similar with your own hands. Although in fact there are several examples of such a device.

Factory option

Before you understand how to make a solar water heater with your own hands, you need to have an idea about the principle of operation of such a unit. You can disassemble the design by analogy with a solar factory water heater.

1. In appearance, the unit resembles a battery, which is assembled from individual components. The elements in it are represented by tubes made of quartz glass like the well-known lamps. It is this material that is able to pass ultraviolet waves (which ordinary glass cannot). This ability allows you to convert solar energy even in the non-solar season.
2. Inside each of these tubes is hidden another - black with a substance ( working body), which will evaporate under certain temperature conditions.
3. Inside the tubes absolute vacuum- this avoids heat loss.
4. The ends of each of these parts are immersed in special collector through which heated water flows.

How the device works

The functioning of this whole idea occurs according to the following algorithm:

1. The sun's rays transform the working fluid into vapor substance, which rises to the top of the flask.
2. The water flow will be heated through the wall by the thermal energy that the working fluid will give it.
3. Having fulfilled its mission, the vapor again becomes a liquid and flows down, where everything is safely repeated.
4. The solar storage standard water heater is connected to a coil, which leads to the boiler of the entire home heating system.

Other heat transfer options

It is clear that in the above case you will not show any initiative. However, there is another option for a non-pressure solar-powered boiler. Here heat transfer is direct: a copper coil is placed in a rectangular case. Then it connects to the storage tank. The water will circulate here in a natural way and immediately heat up from the rays of the sun, increasing the warmth and overall content of the entire storage tank. The serpentine pipe is pressed into a metal plate, which is dark in color. It has additional protection against precipitation with durable glass.

There are also disadvantages here - such a design will work well only in cloudless sunny weather.

Finally, you can simply connect solar panels to a conventional water heater. Such a design turns out to be very expensive to implement, but it can work all year round.

Homemade solar water heaters

The desire for an environmentally friendly approach to home heating is commendable - especially since you can make such a system with your own hands. Consider interesting options for the practical implementation of such structures, and how effective home-made solar water heaters are.

Simple solar water heater

A simple solution would be to install one (maximum two) black tanks on the roof of the house. A house water main is connected to them - which means that with good sun, warm water will flow immediately into the shower room (in summer, in the heat, heating will occur quickly).

Another simple solar boiler is made from shallow trough filled with water, which is covered with a transparent lid. This scheme also includes the following plumbing components:

• a pipe through which cool water flows;
• overflow pipe;
• valve detail;
• hot water outlet.

In both cases, there are significant drawbacks:

1. The inefficiency of a simple tank with clouds.
2. The heater trough should be filled every morning by covering it. When the sun is hidden behind clouds, the degree of heated water should be assessed and drained for further use.
3. A flat device like a trough is bad because it is needed keep horizontal. We do not live in the tropics, which means that in winter the sun rises high above the horizon, the efficiency of this device will decrease.

It is much more efficient to provide for an additional installation of a collector, albeit, again, self-made. Having determined the dimensions of the heat sink, it is necessary to make a housing where the coil is placed. Relevant thermal insulation issue- that is why the case for the coil is better to make wooden. The second point is the insulation of the back wall (preferably with foam).

How to assemble a heat receiver

The simplest solar water heater can be made with your own hands according to the scheme of the following components:

• storage tank;
• make-up capacity;
• collector.

Experts advise not to install a separate pump - water should circulate naturally. But in order to achieve this, the tank should be installed above the heat sink, and the make-up tank - above the storage tank. Another good recommendation is to insulate the tank with heated water. Any material in rolls will do here.

For functioning in an independent mode (when you do not have to top up and adjust), it is best to install float valve in the second tank. This element will react to the falling water level. It is necessary to bring a water pipe to its branch pipe. What will it give? When the contents of the main tank are consumed, cold water will be supplied to its lower zone.

However, we must not forget about the installation of another pipe - vertical: it will release air. Therefore, this part should also be raised to a greater height.

How to choose the right material

There are different source options from which you can make a heat exchanger. Among them:

• copper tubes;
• black polymer pipes;
• sections of flat steel radiators;
• aluminum pipes;
• black rubber hose;
• heat exchanger left over from an old refrigerator.

What should be the heat exchange surface of such a coil? In the case of steel radiators their size should be taken into account, however, in order not to make the case heavier, no more than two panels are installed. With other materials, everything will have to be calculated on the spot.

The body can be made from plywood and wooden boards. On the front side, it is worth using durable and transparent polycarbonate, which will look no worse than glass. The storage tank itself is made from sheet material. It would be even better to purchase a ready-made container. It is recommended to use as connecting pipes polymeric(well suited from metal-plastic).

Features of homemade solar water heaters

The advantages of a do-it-yourself boiler are obvious:

• work at full load for the maximum possible period;
• return on initial investment in materials;
• fuel economy;
• the product is immediately ready for use.

However, all these aspects will turn into positive ones if important conditions are met.

1. Precise setting of device parameters. The calculated load should approximate the standard daily intake.
2. To ensure a constant load on the hot water supply, you can install auxiliary heater. It is recommended to turn it on if the solar does not provide the desired load. This element is needed to eliminate the difference in water temperature.
3. The correct distribution of the load is important, one of the parameters of which is the regulation of the water flow rate.
4. If the water is not planned to be consumed immediately, then the tank needs additional thermal insulation. The last point also applies to cloudy days (the thickness of the thermal insulation should be provided more).
5. The coating of the heat sink should increase its absorption capacity (the simplest can be done with black paint, ideally it is better to apply a selective one).
6. The tank should hold a supply of hot water for two days.
7. The pipes leading from the collector to the tank should be as short as possible and well insulated to maintain the temperature difference.
8. The cold water supply pipe to the collector must be located at the bottom of the tank. Heated water, on the contrary, goes up. Above the opening for the hot water leaving the system, there must be room for its supply.
9. Now about the installation of the tank: if you do it in the building, then the heat loss will be significantly reduced. Even if they are, they will go into the home environment, and not into the air. Here, for example, an attic is suitable. At roof system installation it is important to orient the collector to the south and tilt it at an angle of local latitude (this will increase the efficiency of work for the whole year). The best angle will be 60 degrees in winter and 30 degrees in summer, in practice it is better to immediately give 45 degrees.
10. The structure of the house must be ready to withstand the load of a full tank.
11. And one more important point: how to prevent the system from freezing in cold climates? Can be used insulating removable cover, install a water drain or apply an antifreeze solution in water. The latter option has gained popularity - only in this case it is poured into a spiral coil, through the walls of which heat transfer will occur.

The use of a solar water heater will significantly reduce fuel costs and reduce carbon dioxide emissions into the atmosphere. You can assemble a similar system with your own hands - while it is important to have minimal knowledge in the field of plumbing installations and adhere to all of the above recommendations.

The rise in the cost of traditional energy sources encourages owners of private houses to look for alternative options for heating housing and water heating. Agree, the financial component of the issue will play an important role in choosing a heating system.

One of the most promising ways of energy supply is the conversion of solar radiation. For this, solar systems are used. Understanding the principle of their device and the mechanism of operation, making a solar collector for heating with your own hands will not be difficult.

We will tell you about the design features of solar systems, offer a simple assembly scheme and describe the materials that can be used. The stages of work are accompanied by visual photographs, the material is supplemented with video clips about the creation and commissioning of a self-made collector.

Modern solar systems are one of heat production. They are used as auxiliary heating equipment that converts solar radiation into useful energy for home owners.

They are able to fully provide hot water supply and heating in the cold season only in the southern regions. And then, if they occupy a sufficiently large area and are installed on open areas not shaded by trees.

Despite the large number of varieties, the principle of their work is the same. Any one is a circuit with a serial arrangement of devices, both supplying thermal energy and transmitting it to the consumer.

The main working elements are or solar collectors. The technology on photographic plates is somewhat more complicated than on a tubular collector.

In this article we will consider the second option - a collector solar system.

Solar collectors still serve as an auxiliary energy supplier. It is dangerous to completely switch the heating of the house to the solar system due to the inability to predict a clear number of sunny days

Collectors are a system of tubes connected in series with the outlet and inlet lines or laid out in the form of a coil. Technical water, air flow or a mixture of water with any non-freezing liquid circulates through the tubes.

Circulation is stimulated by physical phenomena: evaporation, changes in pressure and density from the transition from one state of aggregation to another, etc.

The collection and accumulation of solar energy is carried out by absorbers. This is either a solid metal plate with a blackened outer surface, or a system of individual plates attached to the tubes.

For the manufacture of the upper part of the housing, the cover, materials with a high ability to transmit light flux are used. It can be plexiglass, similar polymeric materials, hardened types of traditional glass.

In order to eliminate energy losses from the back of the device, thermal insulation is placed in the box

It must be said that polymeric materials do not tolerate the influence of ultraviolet rays quite well. All types of plastic have a fairly high coefficient of thermal expansion, which often leads to depressurization of the case. Therefore, the use of such materials for the manufacture of the collector housing should be limited.

Water as a heating medium can only be used in systems designed to supply additional heat in the autumn/spring period. If year-round use of the solar system is planned, before the first cold snap, process water is changed to a mixture of it with antifreeze.

If a solar collector is installed to heat a small building that is not connected to the independent heating of the cottage or to centralized networks, a simple single-circuit system is built with a heating device at the beginning of it.

The chain does not include circulation pumps and heating devices. The scheme is extremely simple, but it can only work in sunny summer.

When the collector is included in a double-circuit technical structure, everything is much more complicated, but the range of days suitable for use is significantly increased. The collector processes only one contour. The predominant load is assigned to the main heating unit, powered by electricity or any type of fuel.

Home craftsmen invented a cheaper option - a spiral heat exchanger made of.

An interesting budget solution is the absorber of a solar system made of a flexible polymer pipe. Suitable fittings are used to connect to the inlet and outlet devices. The choice of improvised means from which a solar collector heat exchanger can be made is quite wide. It can be the heat exchanger of an old refrigerator, polyethylene water pipes, steel panel radiators, etc.

An important criterion for efficiency is the thermal conductivity of the material from which the heat exchanger is made.

For self-manufacturing, copper is the best option. It has a thermal conductivity of 394 W/m². For aluminum, this parameter varies from 202 to 236 W / m².

However, the large difference in thermal conductivity parameters between copper and polypropylene pipes does not mean at all that a heat exchanger with copper pipes will produce hundreds of times larger volumes of hot water.

Under equal conditions, the performance of a heat exchanger made of copper pipes will be 20% more efficient than the performance of metal-plastic options. So heat exchangers made of polymer pipes have the right to life. In addition, these options are much cheaper.

Regardless of the pipe material, all connections, both welded and threaded, must be tight. Pipes can be arranged both parallel to each other, and in the form of a coil.

The coil-type circuit reduces the number of connections - this reduces the likelihood of leaks and provides a more uniform movement of the coolant flow.

The top of the box, in which the heat exchanger is located, is covered with glass. Alternatively, modern materials can be used, such as an acrylic analogue or monolithic polycarbonate. The translucent material may not be smooth, but corrugated or matte.

Conclusions and useful video on the topic

The manufacturing process of an elementary solar collector:

How to assemble and commission a solar system:

Naturally, a self-made solar collector will not be able to compete with industrial models. Using improvised materials, it is quite difficult to achieve the high efficiency that industrial designs have. But the financial costs will be much less compared to the purchase of ready-made installations.