The energy of the sun, which gives us light, electricity, heat, is rapidly gaining more and more frontiers. No one will be surprised by various solar-powered devices and devices, home helium power plants, various lamps, street garlands, traffic lights powered by sunlight.
And of course, the logical direction of using solar energy was to use it for heating, heating water not only in a single private house, but also in large houses, in public buildings.
Of course, solar systems are not able to provide round-the-clock operation for heating water. But they are able to replace traditional fossil energy sources - oil, gas, coal - during daylight hours. Since solar heating does not require the consumption of raw materials, there are no harmful emissions into the atmosphere, there is no environmental pollution.
Therefore, the use of solar energy for heating residential buildings, hot water supply will become increasingly important every year against the background of the expected rise in prices for oil, gas, coal.
Solar heating system
In the simplest case, a solar heating system consists of one or more solar collectors connected in a closed circuit with heating fittings - batteries or pipes laid in the floor. In this case, the batteries or floor pipes must be above the collectors.
Then the water heated in the collectors, according to the laws of convection, will rise to the heating sections, and the cold water will descend to the collectors. Batteries or pipes hidden in the floor heat up and thus, without any additional devices, the room is heated.
The simplest scheme of solar heating
But this is precisely the simplest scheme that explains the principle of building a system. In reality, solar heating at home involves the installation of a much more complex system. Before buying solar water heaters or making them yourself, you need to determine what area you need to heat, which home heating system is most suitable for these purposes.
At the same time, it should be taken into account that none of the helium systems will be able to provide round-the-clock operation. To heat the premises at night, it will be necessary to use traditional means of heating, working on one of the fossil energy carriers.
Typical scheme of solar heating and hot water supply
For a small house with one or two rooms, an air heating system from solar collectors can be used. In such installations, air is used as a heat carrier, which, heated in the collector system, enters the heated room through air ducts. Cooled air from this room enters the collector.
Scheme of solar air heating
As for solar heating systems with a liquid heat carrier, in principle they are all built in the same way. The difference lies in the type of collectors used to heat the coolant.
The standard kit consists of manifolds, a storage tank with two heat exchangers (one connected to the manifolds, the other to an additional heater). The storage tank must be provided with good thermal insulation. The circulation of the coolant and water in the heating system is maintained by the pumping group.
flat collector heating system
The design of a flat collector is so simple that it can be freely made by hand. This device is a box, inside of which an adsorber, pipes with a heat carrier, and thermal insulation are placed. For its manufacture does not require any special materials. All components are quite affordable. These are boards, fiberboard, wooden bars, roofing iron, foam plastic, copper pipes, tempered glass, sealing materials, heat-resistant black paint.
Such a well-assembled home-made device is able to heat the coolant in stagnation mode up to 150 ° C. As a rule, water is poured into the system with the addition of antifreeze in such a proportion that this solution does not freeze in winter at night when the solar collector is not working.
Industrial flat collector
The collector or collector batteries are installed in such a way as to provide maximum illumination of them by the sun. As a rule, this is the south side of the roof of the house. The heat carrier circulating in the circuit of the device is supplied by a pump to the heat exchanger located at the bottom of the storage tank. Continuously circulating in this system, the coolant heats the water in the boiler up to 50°C - 60°C, which is quite enough to heat the living quarters.
Flat solar collectors on the roof of a hotel and a private house
To ensure a continuous supply of heat to residential premises at night, a backup water heating system is installed that runs on traditional energy sources - gas, electricity, coal, wood. The coolant circulating in the backup system enters the heat exchanger located above the main one.
This ensures the heating of water in the boiler and a continuous heating cycle. If the backup heating system, working on coal and wood, can only be started manually, then the gas and electric systems can be turned on automatically, under the control of a special control unit.
Heating system with vacuum manifold
This system differs from the previous one only in the design of the collector. In this device, vacuum tubes are used to heat the coolant. In essence, these vacuum tubes are a modified Dewar.
A double glass tube in which air is evacuated from the interstitial space. This ensures reliable thermal insulation of the inner tube. The inner tube contains an adsorber and a copper pipe, the upper end of which has a slightly larger diameter than the pipe itself, and is sealed. The pipe is first filled with a low-boiling liquid.
Under the influence of solar radiation, the tube heats up, the liquid in it begins to boil, the vapor rises into the tip. There he gives up his heat, returns to the liquid state and flows down according to the laws of convection. This process continues continuously, while heating the tip to 250°C -280°C. Fifteen to twenty such tubes are mounted in a single structure - a collector. The tips are inserted into the pipe through which the coolant circulates. The heat carrier is heated up to 60°С - 80°С and fed into the boiler heat exchanger.
Diagram of a vacuum tube
The vacuum manifold itself is installed obliquely to ensure free circulation of liquid in copper tubes. With the exception of the collector, this heating system is no different from a flat-plate collector system.
Vacuum collectors on the roof of the house
Heating system with parabolic trough mirror
Such a device is the most bulky and difficult to operate design. This is a long (several meters) mirror, curved into a parabola. You can make such a mirror yourself by bending, for example, a sheet of plywood and pasting it on the inside with aluminum foil.
Such a parabolic-cylindrical mirror is mounted on a stable frame. A long pipe is installed at the focus of the mirror, through which the coolant circulates. If the focus of the mirror is correctly determined and the pipe is installed in this focus, the temperature along the heating line of the pipe can reach 250°C - 300°C. But this is subject to the correct installation and orientation of the mirror to the sun.
Parabolic cylindrical mirror collector
The last condition is very important, since if the mirror is not properly oriented, the heating power is lost, and the temperature on the pipe drops significantly. To prevent this from happening, the installation with a parabolic trough mirror must be equipped with a tracking device with an actuator.
The tracking device will track the position of the sun and orient the mirror in the vertical and horizontal planes accordingly. This greatly complicates and, consequently, increases the cost of the design.
If, in addition to solar collectors, a set of solar panels is also installed to supply the house with electricity, then as a result, you can get an absolutely autonomous energy supply for the house, which does not depend on the general power supply networks.
Vacuum collectors and helium photovoltaic cells
The sun will supply the house with electricity and heat, and at night the electricity accumulated during daylight hours will heat the water in the backup heating system. The control unit will monitor the timely switching on and off of the necessary devices, regulate the temperature inside the premises. And it's not a distant future. This is already working.
The constant increase in tariffs and the dilapidated state of communications are forcing owners of private houses to actively look for alternative ways of heating. One of the powerful and inexhaustible sources is the Sun, which daily supplies a huge amount of kilowatts of free energy. Necessary install appropriate equipment, and dependence on network resource providers will be a thing of the past.
There is always, although it depends on weather conditions or time of day. For regions where climatic and weather conditions allow get enough kilowatts for heating, this option becomes optimal. solar heating provides a lot of opportunities and advantages, which should be discussed in more detail.
Device and principle of operation
An innovative technology that not everyone has a clear idea about yet. Meanwhile, almost any homeowner has all the possibilities for installing and using the corresponding complexes. Need financial investments exists only for the purchase of apparatus or equipment, everything else he gets for free.
There are two options for organizing solar heating:
- Solar collectors.
More cost method requiring presence a lot of equipment. Photovoltaic cells are used, located in an open area at the right angle for the most perpendicular incidence of sunlight. They work out electricity, which the accumulates in batteries, is converted into alternating current with standard parameters, after which it is sent to heating devices.
Heating from solar panels in a private house gives a lot of additional opportunities. This method has a significant advantage - the electric current generated by solar panels, can be used not only for heating the house, but also for powering any appliances for lighting or other needs.
Solar panels for home heating, the cost of which is quite high, may not be profitable from a financial point of view.
They operate on a different principle. They do not produce, but receive heat energy from the sun, which heats the coolant in containers or tubes. In principle, any container of water exposed to the sun can be considered a collector, but there are special designs that can demonstrate the greatest efficiency. This version of the system is much simpler, cheaper and available for DIY.
The resulting heat is immediately realized in an increase in the temperature of the coolant, which is accumulated in a storage tank, from where it is distributed to the heating circuits of the house. The best heating method is use of low temperature systems such as underfloor heating. They do not need strong heating, which corresponds to the capabilities of solar collectors. At night, the coolant heated during the day is consumed.
For maximum efficiency of solar collectors, it is necessary to insulate the storage tank with high quality.
Advantages
The main advantage is that The sun is a constant and inexhaustible source, stable and completely predictable. Unlike wind turbines, which can be idle for weeks, solar energy is supplied at predetermined time intervals. the only the disadvantage is the possibility of cloudy or cold weather, when the efficiency of batteries and collectors drops. However, modern designs allow you to get a minimum amount even in the most difficult conditions, so no surprises threaten the heating system.
Moreover, one must not forget that solar energy is available for free. If, when heating a house with gas or electric boilers, it is necessary to purchase the equipment itself and then constantly pay for energy or fuel, then solar energy is not paid, which significantly changes the level of profitability of the equipment and the entire system as a whole.
However, we should not forget that solar heating of a private house, the price and labor costs for installation of which often become the main problem, beneficial only in regions with suitable climatic and weather conditions.
An additional advantage is high maintainability of the system and the possibility of increasing its performance. There are no restrictions in this matter - how many panels or collectors are installed, so much energy will be received. If the installed kit was unable to efficiently heat the house, it can always be enhanced by adding the right amount of equipment. This is convenient if you need to rebuild or expand the house, make an extension, etc. There is no need to buy a whole new system.
Types of heating
Photovoltaic cells do not work exclusively for heating, which is a particular case of their use, while solar collectors serve only as power sources for heating circuits. Therefore, let's consider collectors, providing heating with solar panels, the price of which is much lower than that of photovoltaic cells.
There are several designs of solar collectors:
- open;
- tubular;
- flat collectors.
These designs have different capabilities and are used to solve problems corresponding to their effectiveness. Let's take a closer look at them:
Open solar collectors
Open structures are the most simple and even primitive. They are containers, usually black narrow oblong plastic trays filled with water. They are not covered by anything. water is outdoors(hence the name).
Such designs have a lot of disadvantages:
- the ability to give a positive effect only at positive temperatures;
- a relatively small temperature difference in the collector and the external environment is required;
- the durability of such installations is low - as a rule, one season;
- as a consequence of the above - extremely low.
To solve serious problems, such installations cannot be used, so they are used for heating water in outdoor or mobile pools, summer showers, etc. however, there are advantages - such devices are very simple. A solar-powered heater can easily be made independently, and in regions with suitable climatic conditions, its capabilities are noticeably expanding.
Tubular collector varieties
Tubular vacuum collectors are more serious devices that can heat a home or other premises. They consist of the following elements:
- a case covered with black paint and shaped like a flat box;
- distributor (or, as it is sometimes called, manifold, manifold) - a tube with several connecting pipes on the sides;
- vacuum tubes made of glass.
The efficiency of the device ensures the presence of a vacuum, the thermal conductivity of which is practically absent and eliminates losses.
There are several types of tubular collectors, differing in the design of the distributor and tubes:
- Direct Heated Coaxial Tubes. The preparation of the coolant occurs in direct contact with the absorbing surface
- heat-pipe system. The tubes are connected to the distributor through special sockets and give off the heated coolant through them. The design is convenient due to high maintainability.
- U type system. The tubes are double length and bent in half. The beginning is connected to one distributor, and the end is connected to another. This scheme allows you to increase the time of contact with solar heat, thereby increasing the heating efficiency.
- Pen systems. They are a modification of the heat-pipe system, covered with a transparent plate with a vacuum underneath. They give increased efficiency, but have a high price and low maintainability.
Installation of tubular collectors, as a rule, is carried out on the roof of a house.
Flat closed systems
Solar heating at home using flat systems allows you to get high efficiency at relatively low cost. The design is based on a special insulated metal plate with an absorbent coating, which is called an adsorber. A tube with a coolant is soldered onto the plate in zigzags. The front side is covered with a transparent lid, from under which the air is pumped out. Solar heater of this type able to work even at low temperatures. This allows you to provide home heating with solar panels in winter, user reviews allow you to make quite optimistic forecasts about the future of this heating method.
There are simpler types of flat collectors where there is no vacuum. They are less efficient, but the cost and maintainability are much higher. Solar-powered flat-type heating with vacuumless design will be much cheaper, and the ability to restore the panels increases their service life.
Solar collector selection and installation
A homeowner who decides to create solar heating for a private house with his own hands faces the task is to choose the most suitable type of collector. This question is quite complicated, but it is necessary to understand it.
Open collectors are not suitable due to low capabilities, so it makes no sense to talk about them. Usually the choice is made between tubular and flat types. The first and most significant selection criterion is usually the ratio of price and quality of products.
This approach is justified, but maintainability cannot be ignored. So, vacuum tubes can be changed not in all types of collectors which makes the choice risky. If one of them fails, some types of collectors will have to change the entire panel, which will require expenses. In general, all vacuum devices are a rather risky acquisition, since any mechanical impact threatens to lose the source of thermal energy.
Choosing the best option, For him, you need to choose a suitable site, located near the house. This is important, since transporting the coolant over long distances will require high-quality insulation and the installation of a circulation pump. Typically, collectors are installed on the roof to allow circulation by gravity. The only problem is the location of the rays relative to the position of the sun in the sky - sometimes you have to install a tracking system to rotate the panels. This is expensive and requires the use of flexible tubes, but the effect is much higher.
Connection diagrams for the heating system
Do-it-yourself solar heating must be finally implemented by connecting it to the heating system. The best way would be use of underfloor heating, the coolant temperature for which does not exceed 55 degrees. Consider the connection schemes that provide heating of the house with solar energy:
With water manifold
Water collectors directly connected to the heating circuit of the house. There are two connection options: summer and winter.
summer version, as a rule, it is used to supply heated water to the shower or for other needs, since heating of the house is not needed in summer. the simplest - the collector is installed in an open area, the water, heating up, rises into the storage tank, set at a higher level. As it is disassembled, the container empties, so it is constantly fed entering the collector and receiving thermal energy in it. This method is simple and can be easily implemented by hand.
Winter version is more difficult. Collector installed in an open area, delivers hot water(recommended to use antifreeze) into the heat exchanger coil. It is a vertically mounted container with a coil inside. There are two loops - in one the antifreeze circulates (in a circle of the collector-heat exchanger), in the other the coolant circulates (from the heat exchanger to the heating circuit and back). The antifreeze must be circulated with a circulation pump. otherwise the system will not work. The circulation of the coolant can be organized both naturally and forcibly, using a pump. The best option for the heating circuit is a floor heating system that allows you to get the maximum effect both during the day and at night.
With solar battery
Heating from the sun do-it-yourself, created on the basis of solar panels, is carried out by installing an electric heater. In this case, photovoltaic cells only provide power to the heating elements installed in the electric boiler, without being directly related to the heating circuit.
The heating system and solar panels with the entire set of equipment are mounted separately. The connection method is chosen arbitrarily, based on the characteristics of both systems. Connection of the boiler, pump and other devices is carried out in the usual way, there are no specific requirements.
- The operation of the solar heating system is carried out in accordance with the design of the collectors, their number and other features.
- Main task for the owner becomes maintaining cleanliness, timely removal of dust and other contaminants. This allows you to ensure maximum reception of thermal energy, increase the efficiency of the entire system as a whole.
- Necessary qualitatively insulate all connecting pipelines and storage tank excluding heat loss.
- It is recommended that you always keep one or two panels in stock so that in case of mechanical failure you can quickly replace them. Compliance with these simple recommendations will improve the efficiency of the system and ensure comfort and coziness in the house.
Building solar heating for a private house with your own hands is not such a difficult task as it seems to an uninformed layman. This will require the skills of a welder and materials available at any hardware store.
The relevance of creating solar heating for a private house with your own hands
To get full autonomy is the dream of every owner who starts private construction. But is solar energy really capable of heating a residential building, especially if the device for its accumulation is assembled in a garage?
Depending on the region, the solar flux can give from 50 W/sq.m on a cloudy day to 1400 W/sq.m in a clear summer sky. With such indicators, even a primitive collector with low efficiency (45-50%) and an area of 15 sq.m. can produce about 7000-10000 kWh per year. And this saved 3 tons of firewood for a solid fuel boiler!
- on average, 900 watts per square meter of the device;
- to raise the temperature of the water, it is necessary to spend 1.16 W;
- taking into account also the heat loss of the collector, 1 sq.m will be able to heat about 10 liters of water per hour to a temperature of 70 degrees;
- to provide 50 liters of hot water needed by one person, you will need to spend 3.48 kW;
- after checking the data of the hydrometeorological center on the power of solar radiation (W / sq.m) in the region, it is necessary to divide 3480 W by the resulting solar radiation power - this will be the required area of \u200b\u200bthe solar collector to heat 50 liters of water.
As it becomes clear, it is rather problematic to implement efficient autonomous heating exclusively using solar energy. After all, in the gloomy winter season there is very little solar radiation, and to place a collector with an area of 120 sq.m. doesn't always work out.
So are solar collectors non-functional? Don't discount them ahead of time. So, with the help of such a drive, you can do without a boiler in the summer - there will be enough power to provide the family with hot water. In winter, it will be possible to reduce energy costs by supplying already heated water from a solar collector to an electric boiler.
In addition, the solar collector will be an excellent assistant to the heat pump in a house with low-temperature heating (warm floors).
So, in winter, the heated coolant will be used in underfloor heating, and in summer, excess heat can be sent to the geothermal circuit. This will reduce the power of the heat pump.
After all, geothermal heat is not renewed, so over time, an ever-increasing “cold bag” is formed in the thickness of the soil. For example, in a conventional geothermal circuit, at the beginning of the heating season, the temperature is +5 degrees, and at the end -2C. When heated, the initial temperature rises to +15 C, and by the end of the heating season does not fall below +2C.
Homemade solar collector device
For a self-confident master, it is not difficult to assemble a thermal collector. You can start with a small device for providing hot water in the country, and in case of a successful experiment, move on to creating a full-fledged solar station.
Flat solar collector made of metal pipes
The simplest collector to perform is a flat one. For his device you will need:
- welding machine;
- pipes made of stainless steel or copper;
- steel sheet;
- tempered glass or polycarbonate;
- wooden boards for the frame;
- non-combustible insulation that can withstand metal heated to 200 degrees;
- matte black paint resistant to high temperatures.
The assembly of the solar collector is quite simple:
- The pipes are welded to a steel sheet - it acts as an absorber of solar energy, so the pipes should fit as tightly as possible. Everything is painted matte black.
- A frame is placed on the sheet with pipes so that the pipes are on the inside. Holes are drilled for the entry and exit of pipes. The heater is installed. If a hygroscopic material is used, you need to take care of waterproofing - after all, wet insulation will no longer protect pipes from cooling.
- The insulation is fixed with an OSB sheet, all joints are filled with sealant.
- On the side of the adsorber, transparent glass or polycarbonate with a small air gap is placed. It serves to prevent the steel sheet from cooling down.
- You can fix the glass using wooden window glazing beads, after laying the sealant. It will prevent cold air from entering and protect the glass from compressing the frame when heated and cooled.
For the full functioning of the collector, you will need a storage tank. It can be made from a plastic barrel, insulated from the outside, in which a heat exchanger connected to a solar collector is laid in a spiral. The hot water inlet should be at the top and the cold outlet at the bottom.
It is important to place the tank and manifold correctly. To ensure natural circulation of water, the tank must be above the collector, and the pipes must have a constant slope.
Solar heater from improvised materials
If it was not possible to make friendship with the welding machine, you can make a simple solar heater from what is at hand. For example, from tin cans. To do this, holes are made in the bottom, the banks themselves are fastened to each other with a sealant, and they sit on it at the junctions with PVC pipes. They are painted black and fit into a frame under glass in the same way as ordinary pipes.
Solar house facade
Why not decorate the house with something useful instead of ordinary siding? For example, by making a solar heater on the south side of the entire wall.
Such a solution will allow to optimize heating costs in two directions at once - to reduce energy costs and significantly reduce heat losses due to additional insulation of the facade.
The device is simple to disgrace and does not require special tools:
- a painted galvanized sheet is laid on the insulation;
- a stainless corrugated pipe, also painted black, is laid on top;
- everything is covered with polycarbonate sheets and fixed with aluminum corners.
If this method seems complicated, the video shows a variant of tin, polypropylene pipes and film. How much easier!
Owners of country cottages often install solar panels for home heating. The popularity of this design is easy to explain: fuel savings and an environmentally friendly life support system. With the skillful use of the energy of the sun, wind or water, it is quite possible to turn a small country house into a modern eco-housing. But first, it’s worth figuring out how to do this and how beneficial such batteries are for residents.
Usage Methods
The energy of sunlight has been used for a long time and successfully, so the technology is not an innovation. But this service is most often used by residents of hot countries and southern latitudes, since in warm climatic conditions it is possible to extract such an alternative resource all year round. But the northern regions, where there is a lack of natural radiation, use solar heating only as an additional option.
A kind of intermediaries between the sun and the mechanism that generates energy are solar panels and special collectors. Moreover, these elements can differ both in purpose and in design. But the essence of their work is to accumulate solar energy for later use.
The batteries are presented in the form of panels, on one side of which there are photocells, and on the other - a locking mechanism. It is quite possible to mount such a design on your own, but you can purchase ready-made products that are sold in a wide range.
Solar panels for the home.
Solar system - a device that is part of the heating system. It is a large heat-insulated box in which the coolant is built. Such a device, together with batteries, is fixed on a raised shield facing the luminary. It is also possible to simply lay the heating elements on the roof slope.
It is possible to significantly increase the efficiency of the heating system by placing batteries on special dynamic mechanisms. These devices work on the principle of a tracking system, that is, they turn in the direction where the sun's rays are directed.
The transformation itself is carried out in pipes that are located inside the box. Using solar panels to heat a house in winter is quite realistic, but on the condition that there will be at least two hundred sunny days a year.
Pros and cons
A system that allows you to heat your home with solar energy has a large number of positive qualities. Each of them is quite weighty, which allows residents to experiment. The main advantages of batteries are as follows:
Heating from a solar power plant
In addition to the positive aspects, there are also negative aspects. For example, it takes a long time (from 3 to 5 years) to determine how well and efficiently the system works. During this period, there should be enough energy and it must be used in an active mode. . The disadvantages of solar panels can also include the following factors:
- high cost of components required to connect and launch the structure;
- the amount of heat produced depends entirely on the geographic location and weather conditions;
- housing needs a backup source (gas or solid fuel boiler).
It should be taken into account that for efficient operation it is necessary to constantly monitor the cleanliness of the installation, remove frost from its surface, and repair breakdowns. If the temperature regime in the region often drops below 0 ° C, then you will have to additionally insulate both the collector itself and the house as a whole.
It should also be borne in mind that such systems are not suitable for everyone. For example, in regions where sunny days are rarely observed, the design is unlikely to justify itself. But, despite the high cost, the plates are very popular, so more and more often they can be seen on summer cottages and rooftops.
Main types
There are two types of batteries: small and large photovoltaic systems. The first type includes battery panels that operate on a voltage of 12-24 V. With their help, you can watch TV and turn on several lighting devices.
Large installations are able to provide electricity to the entire house, and if necessary, completely heat it. But this applies only to small private cottages, they will not be able to heat multi-storey buildings.
As for the equipment, it may vary depending on the model. As a rule, the basic set includes:
- vacuum solar collector;
- a special controller that monitors work efficiency;
- a pump with which the coolant is supplied;
- a tank with a volume of 500-1000 liters for hot water;
- electric heater or heat pump.
How many solar collectors will 100% heat a house (type 12 100% solar heating)
All these details are necessary for the normal functioning of the system. How exactly to mount and use them is prescribed in the instructions, which are also included in the kit.
When equipping a powerful home heating system with solar panels, you can additionally provide a home with hot water, as well as install a warm floor. A large photovoltaic installation will cope with these functions quite well.
Before installing collectors, it is necessary to calculate how much power they need in order to fully satisfy all needs. When calculating, it is worth considering the area of a private house, the number of people living, as well as energy consumption. For example, for a small family of three, on average, from 200 to 500 W / m² will be required per month.
If you plan to provide a home with hot water, then energy costs will increase. For efficiency, you can make a combined version of the heating system. In this case, households will be insured and will not be left without heating in emergency and unforeseen situations.
