Solar air collectors as a ventilator. Making an air solar collector with your own hands. Installation and connection of the air manifold

Agree, strange spring this season. The sun is shining brightly and it seems warm, but the temperature outside is 8 -11 degrees Celsius. And, nevertheless, I am happy to notice that in my apartment, the bay window of which is located to the south, sunlight, penetrating through the glass, brings energy and warmth to the rooms. My efforts to use the greenhouse effect paid off.

Poltava resident Vitaly, using the same principle, built his house with a domed roof and heats the rooms with solar air collectors. Using solar energy to heat the house, it practically does without natural gas, coal and firewood.

Vitaly is happy to share his experience and this is what he says: “The main material for the construction of a two-story house was ordinary foam plastic. Anyone can build such housing. The premises on the second floor are heated exclusively by solar-air collectors.

In order for warm air to be drawn into the room faster, I installed ordinary fans such as a computer cooler, which consume only 1 W of electrical energy and are powered by a solar battery. As a result, we do not waste electricity, and most importantly we receive heat thanks to solar air collectors.

The solar air heater, made with my own hands, cost me 500 hryvnia. An autonomous device that operates using solar energy does not require additional costs. Six solar air collectors heat the entire second floor of the domed building, even in winter.”

Based on the experience of the Poltava innovator, I decided to get acquainted in more detail with the principle of constructing solar air collectors. Fortunately, there is enough material for this. I note that the designs of such devices may be different, but the principle is the same - the black surface (absorber) absorbs solar heat and releases it to the air.

Technology and manufacturing of the air manifold

It is based on a design developed by the famous Ukrainian inventor Yuri Dudikevich.

While the sun shines on the collector, the absorber heats the cold home air pumped by the fans. Already heated air returns to the room - thanks to such ventilation, the temperature in the room gradually increases.

An airborne solar collector is usually installed on the roof or on the southern wall of the house, but for this you must first make four holes with a diameter of about 10 cm.

Through the lower openings in the wall, cool home air is supplied to the collector, heated and returned back into the room through the upper openings. Check valves are installed at the collector outlet, which block air movement when the fans are turned off.

According to Yuri's calculations, the airborne solar collector allows one to receive 1.5 kW. h of thermal energy per square meter of area. For example, 10 collectors, each two meters in area, can produce 30 kW. h on a sunny day. In December, when the outside air temperature reached -6 ° C, the total thermal output of the collector during a sunny day (7:00) was 6 kW. h, and the efficiency is at least 50%, and in October the efficiency of the device increases to 75%.

It is better to direct the warm air from the solar heater under the floor, through flat rectangular air ducts 30 centimeters wide and 5 centimeters high. They are made from galvanized sheet metal, having previously been thermally insulated; they have a larger surface area than round pipes and therefore transfer heat better.

To make a solar air heater that can work in winter, you will need a wooden frame with a plywood bottom, insulating and reflective film, metal sheet, blackened mesh and a transparent polycarbonate sheet. In addition, two fans are needed, and two check valves, which are installed at the outlet of the manifold.

A plywood bottom measuring 1500x1500 mm needs to be cut into two parts: 1050x1500 mm and 450x1050 mm (connected by a strip with a cross-section of 20x40 mm) and cut four holes for the movement of ventilated air.

An insulating film with heat-reflecting properties is placed in the bottom, then two holes with a diameter of 10 cm are drilled from below to take in cold home air and two holes from above to remove hot air from the collector. Fans are installed in the lower openings, with the help of which cold air will be drawn into the collector, and check valves are installed in the upper openings, which block the movement of air when the fans are turned off.

The main element of the collector is the absorber - a metal sheet painted black.

A metal mesh is nailed to the inside of the absorber, which changes the structure of the air flow created by the fans, and this entire structure is mounted to the collector frame.

Cold home air drawn into the collector moves along the grid, warms up and becomes temperature uniform.

For the collector, two Domovent VKO-100 fans are used, which create an air flow of 200 m3/h. The power consumption of one fan is 14 W with daytime solar input to the collector starting from 3 kW. h and above.

To install the air collector on a vertical wall (preferably on the south side), it is necessary to drill four holes with a diameter of 10 cm. To reduce heat loss, the absorber is covered with a sheet of transparent polycarbonate, which has a protective film against harmful ultraviolet radiation.

Now, I hope, those who wish can independently make a solar air collector to satisfy their own ambitions and to the delight of their family in creating comfortable living conditions in the house.

The essence of the operation of such solar air collectors is the thermosiphon and greenhouse effects. In order to understand how a solar collector of this type works, it is enough to remember the operating principle of an ordinary greenhouse. Everyone knows that solar heat easily passes through transparent glass.

Leave the car in the sun and you will return to a real sauna, because the same glass prevents the release of stagnant heat outside. Now the following: everyone also knows why the smoke in the chimney comes up, why is a warm floor more effective than radiators? Right! Warm air always tends upward. It is these two effects that the operating principle of a solar air collector is based on.

In essence, the solar collector does not draw in or out air. Everything happens under natural processes. A special absorber can only help with air intake. Of course, the downside is that fans absorb additional energy, while devices operating on the principle of natural convection do not consume any energy at all. Also, as an option, special fans can be soldered onto the absorber plate to increase turbulence to increase efficiency.

An important point is also that air is much less capable of transferring heat than water. Thus, much less heat is transferred to the heat sink than would be the case with water.

Advantages of air solar collectors for heating

What is the main advantage of air collectors? The most obvious advantages are reliability and simplicity. There's really nothing to break there. If the collector is properly cared for, then with proper quality equipment, it can last up to 20 years. The main complex element is simply missing here; a heat exchanger is not needed, because the air does not freeze.

To make the air collector even cheaper, such an air heating system is usually installed and integrated directly into the walls of the house.

What is the difference between ventilation and recuperation solar air heating systems?

Air collectors differ from each other in the principle of heat intake into the room. There are two methods: ventilation and recovery.

Ventilation: air return is not expected and only warm air from outside enters the premises. Such systems are used in large workshops, hangars or vegetable warehouses.

Recovery or recirculation: The air from the room circulates again and again in the heating circuit, constantly heating the air. When using such a system, special heating heaters are integrated into the air ducts, which return already heated air to the system. Of course, it is necessary to think through such a heating system when designing a future building.

Finally, I would like to say about the economic feasibility of air heating, which is undoubtedly more profitable than conventional water heating with a circulating coolant.

When it comes to solar collectors, first of all, associations arise with the already familiar flat or vacuum models. The energy of the sun is transferred to them through water or antifreeze, in other words, a liquid coolant. Such liquid collectors have already appeared in many homes and have ceased to cause any surprise. But besides liquid collectors, there is another type of collectors, which is much less common, although in some situations it is no less effective. This is an airborne solar collector.

Features and Application

Its main difference from liquid options is the coolant, the role of which is played by ordinary atmospheric air. In essence, such a collector is a flat ribbed panel (often perforated) or a pipe system made of heat-conducting metal (however, plastic is sometimes used). In such a collector, the air is heated due to direct contact with the metal, and ribbing is necessary to increase heat transfer. The entire system must be reliably thermally insulated. The air collector is placed on the southern wall of the house, and air circulation can be either natural, convective, or forced (using fans).

It operates at much lower temperatures than liquid models. Thus, in conventional solar systems, the temperature on the collectors should be more than 45-50°C; for air systems, 25-30°C is sufficient. As a result, heat loss is reduced and overall efficiency is increased. However, since the thermal conductivity of air is quite low, such a collector is used very limitedly.

It is used mainly in dehumidification plants (in agriculture), in air heating systems and in indoor air recovery complexes. That is, such systems cannot be considered as a full-fledged alternative to liquid collectors, but they may well reduce overall utility costs.

Advantages and disadvantages

Like any system, airborne solar collectors have their advantages and disadvantages.

Advantages of air collectors:

Simplicity of design;
Minimum cost;
Efficiency in air drying systems.

Their disadvantages include their rather low efficiency, the inability to use them for heating water, and the rather significant dimensions of the collectors themselves (due to the low specific heat capacity and low air density).

To increase the efficiency of such systems, they are often integrated into the walls of agricultural buildings at the design stage

DIY making

Since the solar air collector has a very simple design, making it yourself is not that difficult. For this, the most commonly available materials and available means are used (some even make such collectors from aluminum cans). However, we must remember that such systems are very large due to the characteristics of the air coolant, so to obtain a noticeable effect you will need to assemble products of considerable size (often the entire length of the wall).

Drain pipe collector

It is better to make such a solar heater on the entire wall of the house. In the spring-autumn period, it will help to significantly save on energy resources. Taking into account the dimensions of the device, materials are also selected.

For the frame:

Board about 30-40 mm thick;
Moisture-resistant plywood (for the back wall) about 8-10 mm thick.

For absorber:

Drainpipes made of aluminum (preferably rectangular);
Thin sheet of aluminum;
Mounting clamps.

You will also need mineral wool to insulate the rear wall of the housing and polystyrene foam to insulate the side surfaces.

Such a solar collector is assembled as follows. First of all, a wooden case of given dimensions is made (in the form of an open box), the depth of which is a couple of centimeters greater than the height of the pipe walls. Then the back wall and side surfaces are reliably insulated, and a thin sheet of aluminum is laid on a layer of mineral wool, to which the pipes are attached with mounting clamps. For better fixation and to ensure air circulation, the pipes must be laid so that on one side of the body they are spaced approximately 20 cm from the end. The edges of the pipes must be secured not with clamps, but with a wooden partition in which the appropriate cutouts will be made.

Since the inlet and outlet of this collector will be located on one side, there should be several wooden partitions in the housing at the opposite end to separate the air flows. After assembly, the collector is painted with black paint, and cellular polycarbonate can be used as the front panel.

It is worth remembering that the finished product is very heavy, so several people will be required to install it. It is located on the south side of the house on stable supports. The collector is connected to the ventilation system of the house through insulated air ducts, and a duct fan is used to deliver air to the rooms.

This is a simpler version of the air manifold. You can do it yourself much faster. In the same way, a wooden box of the required dimensions is made, then a beam of approximately 40x40 mm is laid along the perimeter of the rear wall, and a layer of mineral wool is laid on the bottom. The only thing is that you need to make an outlet hole in the bottom. Then a sheet of corrugated board with a high rib profile is laid on the beam and painted with black paint (if the sheet itself is a different color). Next, perforations are made in the corrugated sheet for air flow.

The entire structure can also be glazed with polycarbonate to increase the heating temperature of the absorber, but it is necessary to provide an inlet for the intake of cold air. A small fan should be placed at the outlet.

Such a homemade collector gives a less significant increase in temperature (usually on a sunny day the heating is about 28°C relative to the outside air). However, it can significantly improve the indoor microclimate, as it provides a constant flow of fresh heated air.

Air is used as a coolant in a solar heating system. Solar collectors heat it and send it to heat the house or heat the heat storage tank. The air type solar heating system is the simplest and cheapest way to implement solar heating at home.

Main features of the air heating system:

Type of heating system – air-solar separate, i.e. technical air does not mix with room air
Air heated floor of the first floor
Airborne solar collectors integrated into the roof and southern facade of the house.
Water seasonal heat accumulator of high heat capacity.
Auxiliary heat source is a fireplace and infrared film heating in the bathrooms.
Power reserve is 30% for the coldest winter months - December and January.

Main components of a solar heating system:

Solar water collectors integrated into the roof and southern façade
Water heat accumulator
Air distribution system

The peculiarity of the solar air heating system is that all its elements are built into the building and are its integral part. This minimizes the number of air ducts and heat loss during the storage and movement of thermal energy. An important advantage of the heating system is that it is separate, i.e. the air in the rooms does not mix with the technical air used as a coolant and circulating through solar collectors, a heat accumulator and the underground.

Moving air does not carry or accumulate dust, bacteria and microorganisms found in every home.
Air movement does not cause discomfort to people in the house with additional noise and the feeling of a draft.
The design of a separate heating system does not provide for the construction of many air channels, especially horizontal ones, in which dust may accumulate over time.
The only horizontal air channel, which is located under the very ridge of the roof, is of sufficient size for maintenance and cleaning.

Solar air collectors

in the winter months, the intensity of solar radiation on a vertical surface is higher than on a roof surface with a slope of 38°;
in case of snowfall, when the solar collector on the roof is completely closed, the vertical collectors remain clean and heat the air with the first rays of the morning sun. Warm air rises and enters the inclined solar collector on the roof, heats it up, melts the snow, and the collector begins to work. Any other flat-plate collectors or vacuum tubes installed on a sloped roof do not have this advantage and start working much later.

The inclined solar collector for heating is a multi-layer roof. The main element that absorbs solar thermal energy is a perforated galvanized metal sheet of anthracite color, covered with a translucent material.

Seasonal heat accumulator

air flow
through your walls directly into the premises

The air flow system is designed in such a way that when charging the heat accumulator, hot air moves from top to bottom, and when discharging, in the opposite direction. This ensures good temperature stratification over the entire height of the heat accumulator: i.e. in the upper part it is always hot, in the lower part it is cool. It is in the upper part that the hot water preheating tank is located, and from the upper part hot air is drawn in for heating. And the lower cool part ensures maximum extraction of thermal energy from the hot air coming from the solar collectors. This increases the efficiency of the entire system.

Heat distribution system

The solar heating system is fully automated and operates in four main modes:

Heating the house on a sunny day
Heating the heat accumulator
Heating a house using a heat accumulator
Summer cooling mode

1. Heating the house on a sunny day.

2. Heating of the heat accumulator.

When the rooms are already sufficiently warmed up, warm air begins to heat the heat accumulator. This mode works mainly in autumn and in the second half of a winter sunny day, when the house is warm and heat storage for the future is required. Hot air passing through the heat accumulator heats it up. As the air descends, it gradually releases its energy and cools down as much as possible below. From the bottom of the heat accumulator, the air is directed again to the solar collectors. The cycle repeats. At the same time, the movement of air flows is organized in such a way that excessive heating of the concrete floor of the first floor does not occur. It should also be noted that both air flows, for heating the heat accumulator and heating the first floor, can flow simultaneously. They can also smoothly change their speed and redistribute the heat flow depending on the temperature of the rooms, the heat accumulator and the hot air leaving the solar collector. If, say, the temperature of the incoming air is 600C, then supplying all the air for heating will quickly lead to overheating of the living quarters. At the same time, it is unwise to lose precious heat, so part of the air is directed to the heat accumulator. Control of this process is fully automated and no human intervention is required. Based on the readings of temperature sensors, the differential thermostat smoothly regulates the speed of rotation of the fans, directing warm air flows in one direction or another.

3. Heating the house using a heat accumulator.

This mode works at night and on cloudy winter days. At night or during prolonged cloudy weather, when there is no solar heat or it is insignificant, warm air for heating the house comes from a heat accumulator to heat the concrete floor of the first floor. In this case, the air flow in the heat accumulator changes to the opposite one that flowed when it was charged with heat. This also maintains good temperature stratification across the entire height of the heat accumulator, keeping its top always hot.

4. Cooling mode.

cooled fresh air from the ground heat exchanger is supplied to the premises through grilles in the floor of the first floor, cools the first floor, and, heating up, rises to the second floor, displacing warm air. The outflow of warm air occurs from the top of each room in the attic floor through air intakes, from where it enters the solar collectors. When heated in the collectors, the air moves upward, creating natural draft, and ultimately comes out through a gap in the upper part of the roof. In this way, a solar heating system becomes a solar cooling system, and it operates completely automatically without electricity or any mechanical moving parts, only using solar energy and the laws of physics. As soon as the sun rises and the collectors begin to heat up, a draft arises in them and the air leaves them, creating some vacuum in the house. With the windows and doors closed, there is nowhere for air to enter the house; it is drawn through the ground heat exchanger and distributed among the floors.

cold fresh air is supplied to the upper part of the rooms on the second floor, and the air outflow is from the lower part of the first floor, and then to the solar collectors and outside. To supply fresh air in this scheme, a fan will already be required, because The collector capacity is not enough to ventilate the entire house. The collectors work only to extract warm air, and to supply cold air, a heating system fan is used, operating in reverse mode in the summer.

It should be noted that the first option is simpler in design and more economical to operate, but is inferior to the second in terms of comfort. In the first option, with the forward movement of air from bottom to top and its gradual heating, the first floor is always cooler than the second. In the second option, cold air, when supplied from above, gradually descends and mixes with warm air located below. Gradually moving downwards, it cools both floors evenly, and eventually leaves the lower part of the premises of the first floor through special air intakes.

Solar water heating system

At the top of the heat accumulator, where the temperature is always at its maximum, there is a metal tank for preheating hot water. The tank is designed without insulation to directly heat the water with hot air coming from the solar collectors.

The tank serves to preheat water to a temperature of 40-500C, which in most cases is sufficient for domestic needs. In addition to this, a backup instantaneous electric water heater is installed after the tank.

Solar water heating, solar air collector

air solar heating system, solar collectors for home heating, solar air collector

The sun is a powerful source of energy that people have learned to use for their needs. The simplest example of how the sun's rays can be put to good use is a shower container painted black. A more complex and functional design that you can make yourself is an air solar collector. With the help of such equipment you can not only heat water, but also heat your house.

Heating a house using a solar collector is not its only function

Operating principle

All solar collectors work on the same principle: The energy from ultraviolet rays is converted into heat. The main structural element is a collector, inside of which there are thin tubes with coolant. Antifreeze or water is usually used as the latter.

The coolant moves through the tubes and heats up under the influence of sunlight. It circulates through tubes inside the tank containing water. While the main volume of liquid heats up, the coolant cools down, and due to this, it circulates through the pipes. The principle is similar to how the cooling system works in cars: excess heat is removed from the engine and used, for example, to maintain the temperature in the cabin.

The difference between an air-solar collector and a cooling system in a car is as follows: heat is not simply removed from one place to another, but performs a specific function. Every year solar collectors are becoming more widespread, and scientists are confident that these devices are the future.

Soon, most likely, solar panels will be in every private home

Interesting facts indicating that soon the sun's rays will be used everywhere as a source of energy:

an air solar collector for heating a house is relatively simple and can be made with your own hands;
the resulting energy can be accumulated and directed to various needs;
heat does not need to be transported, but is used in the same place where it was received;
the process of converting solar energy into heat is harmless to the environment;
collectors do not require expensive maintenance, maintenance is minimal;
Solar energy is endless and virtually free.

But this heat source also has disadvantages. One of them is the inability to receive solar energy at night . Other disadvantages:

The efficiency of the equipment directly depends on the insolation characteristics, i.e. in cloudy weather, as well as during periods when daylight is short, less thermal energy can be obtained;
the creation and installation of a collector will require financial and time costs;
in winter, efficiency decreases noticeably.

In this video you will learn everything about the airborne solar collector:

Device classification

Solar collectors are divided into double-circuit and single-circuit. The first type is more common. In a device with two circuits, water circulates through one of them, and coolant circulates through the second. This collector is used year-round.

As for single-circuit equipment, it is suitable for use only during frost-free periods, since there is water inside the coolant that can freeze and destroy the tubes.

According to the principle of operation, collectors are also divided into several groups:

air;
flat;
vacuum;
hubs.

There are several types of models, for example, air

Air models

The peculiarity of these collectors is their low efficiency. Air is a poor conductor of heat, although it can heat up. The main advantage is the possibility of year-round use. Since the air does not freeze, there is no risk of the tubes being damaged. Structurally, this type of collector is reliable and simple. Such equipment is suitable for heating different types of premises, including:

residential buildings;
basements;
vegetable storage;
workshops;
garages;
warehouses.

The main element of the collector is a ribbed panel that acts as a heat sink. It is usually made of steel, aluminum or copper. Inside, the panel is divided into cells. The air circulates between the fins and is heated, releasing heat into the room. The cooled coolant moves back to the main part of the collector.

Airborne solar collector made from beer cans: consequences of work after winter:

In Russia, it is advisable to use an air collector as the main source of heating in the south, and only in small rooms intended for temporary residence. In other cases, as well as in regions with harsh climates, it is better to use a different type of model.

Flat heat source

The main advantage of a flat solar collector is its simplicity of design. The equipment is quite reliable, but has a relatively low efficiency. The device is assembled according to the sandwich principle and includes the following elements:

protective glass;
copper tubes filled with coolant;
thermal insulation layer;
aluminum frame;
fasteners;
absorbent.

The plate acts as an absorbing surface (absorbent). It is painted black to maximize absorption of sunlight. Glass is used to create a greenhouse effect. Thanks to it, the heat does not escape, but heats the absorbent. This design is easy to assemble yourself, and it can serve for more than 10 years.

There is a vacuum model, which has its own characteristics

Equipment on vacuum elements

Vacuum-type collectors are based on sealed tubes filled with coolant and a heat collector. The tubes are made of glass coated with a special coating, which allows for better heat accumulation. Thanks to the vacuum, heat loss is prevented. During the circulation process, liquid from the vacuum tubes flows first into the heat collector and then into the storage tank with water. The cooled coolant is returned back to the system.

A vacuum (evacuated) device has a higher efficiency than a flat and air device. Using this collector it is convenient to heat water. The good thing about the design is that tubes can be added and removed as the need for hot water increases or decreases.

My air manifold assembly before operation:

There are many options for vacuum devices, including those where glass tubes are located one inside the other, and the outer one contains water. The disadvantage of models of this type is the complexity of manufacturing. It is impossible to create a vacuum at home. Enterprises have this opportunity, however, the process of manufacturing evacuated collectors is not cheap.

DIY assembly

A collector powered by solar energy can be either assembled or purchased ready-made. The second option is inconvenient because as the absorption area increases, the price increases. In this case, the power depends on the size of the absorbing surface. Assembling the air manifold with your own hands is the best option for those who do not want to overpay. Manufacturing does not require expensive tools and materials: in the simplest version, the heating device is assembled from aluminum cans.

When choosing from different types of structures, it is better to choose an air or flat device. The main thing is to be able to prevent heat loss. If you can do this, the design will pay for itself in a few weeks.

The first stage is choosing the place where the device will stand. It should be illuminated by the sun for as long as possible. The panels are oriented to the south, and it is desirable that they can be rotated by adjusting the angle of inclination. This way it will be possible to achieve the maximum level of insolation at different times of the year. For example, in winter the sun is lower above the horizon than in summer.

Air solar collector:

To reduce heat loss, the collector is located as close as possible to the room that is planned to be heated. In particular, you can install it on the gable or south side of the roof. Another important point is shadows from fences, trees and other tall objects. In winter they are longer, and you need to take this into account. The collector should be placed so that shadows do not fall on it at any time of the year.

When a location has been chosen, production begins. Aluminum cans work better than anything else because the metal heats up well and conducts heat. The containers fit together without any problems, since they have the same dimensions, and if necessary, they can be cut and bent.

This heating system can be assembled with your own hands.

Having collected a sufficient number of aluminum cans, cut holes in them on both sides. They are joined together and the joints are sealed with sealant. The structure of cans is painted with black paint and placed in a panel. Then the tubes for air removal and supply are connected. Elements intended for installation of ventilation systems are suitable. Thermal insulation material is installed on the back side of the panel, and glass or cellular polycarbonate is reinforced on the front side. The finished collector can operate without additional equipment, but to increase efficiency, you can connect a fan to it.

Another option is to combine the device with the ventilation system of the living space. Passing through the system, the air will heat up by 30-35 degrees.

A homemade collector makes it possible to organize water heating at home. In this case, the function of heat sinks is performed by polyethylene hoses, metal pipes, aluminum or cast iron batteries. For year-round use, a double-circuit collector is built. The coolant is antifreeze or antifreeze.

By assembling a solar air collector with your own hands, you can completely cover the need for hot water and reduce the cost of heating the room.

Do-it-yourself air solar collector made of corrugated sheets: