How expedient is it to use alternative sources of thermal energy for heating? Currently, two types of heat supply are widely used - geothermal and heliosystem. The latter is the most popular. How to make solar heating at home with your own hands: collectors, batteries and installation diagrams?
Using solar energy for heating
One of the defining principles of building any heating system is expediency. Those. all investments should pay off within a certain period of time. In this regard, heating a home with solar energy is the most efficient and financially beneficial investment.
Solar energy is essentially a free source of heat. It can be used in several ways - to equip a heating system or to make an autonomous hot water supply system. If you carefully study the reviews about heating from solar panels, you can identify an interesting dependence. The more professional the heating is done (factory collectors, additional heating, electronic control), the higher the efficiency of the heat supply.
In what ways can the transformation of solar energy into thermal energy take place?
- Solar heating battery - as one of the ways to obtain electrical energy. Radiation acts on a matrix of resistor photocells, as a result of which a voltage is generated in the circuit. In the future, this current can be used to connect to electrical heating appliances;
- Modern heating of a private house solar collectors... In this case, there is a direct transfer of thermal energy from solar radiation to the coolant. The latter is located in a pipeline system located in a special sealed enclosure.
Heating with solar energy is most efficient in the latter way. In this way, additional energy conversion can be avoided. The sun will directly affect the coolant, increasing its temperature. However, heating with solar energy with your own hands using electric batteries is more versatile, since electricity can be used to operate other electrical appliances in the house. The choice is determined by the budget and the required system capacity.
When installing the solar panel, a certain angle of inclination must be observed. Depending on the season, it should be 30 ° (summer) and 70 ° (winter).
The relevance of the organization of the solar system
Before purchasing or making your own converter, you should find out whether heating a private house with solar panels will be efficient enough. To do this, it is necessary to conduct a detailed analysis of all factors affecting the efficiency of the future system.
To begin with, the indicator of solar insolation is determined. This is the amount of solar energy falling to the surface of the earth in a particular region. The degree of heating of the coolant or the amount of generated current will depend on this.Solar radiators for home heating should ideally work regardless of the season. However, in fact, this is not always the case.
Also, a passive solar heating system can change its efficiency due to the angle of inclination of the panel. It also depends on the season. To determine the theoretically possible energy, you can use the data from the table.
Already on the basis of these data, it is possible to calculate the solar collector for heating, taking into account its technical and operational characteristics. But besides this, such factors should be taken into account:
- Home location... The fall of the sun's rays should not be impeded by natural or man-made objects - mountains, tall houses, tall forests, etc .;
- Place for installation... Combined solar heating will require a large space - from 2 to 10 m². Most often, the roof of the house is used for this. Moreover, it must be adapted for the installation of collectors or solar panels;
- Required heat output... Often, solar heating systems for a private house are used as auxiliary ones.
Only after this analysis can you start choosing a specific scheme for alternative heating at home. Heat losses in the house are calculated in advance, the optimal thermal mode of heating is determined. If the solar collector in the heating system is auxiliary, the same indicator of the main heat supply system is added to its rated power.
When calculating, you need to take into account the weight of the equipment. The roof surface must be able to withstand this load.
Solar panels for heating
There is often confusion - solar collectors are also called batteries. But in practice, it is the first type of equipment that is most often used to organize home heating with solar energy.
The principle of operation of heating a private house with solar panels is to convert thermal energy into electrical energy. For this, the following components are provided in the panel design:
- Photocells... When sunlight hits them, a so-called photocurrent is formed;
- Protective transparent case... Prevents damage to photocells;
- Electric current converters - inverters, transformers, batteries, etc.
Those. in fact, a solar heating battery is a great charger. First of all, it is intended for obtaining cheap electrical energy. Its use as one of the heating elements is impractical. To supply heat to a house with an area of 60 m² with a normal insulation rate, 6 kW of heat energy per hour will be required. A standard solar heating battery with a size of 284 * 254 mm has a specific power of 5 W / h. Those. to provide heat supply, a battery coverage area of 82 m² is required.
As can be seen from the calculations, this is more than impractical. That is why they prefer to make a solar collector for heating with their own hands or purchase factory settings.
Instead of heating a private house with solar panels, they can be used as a source of cheap electricity to operate low-power household appliances.
Choosing a solar collector
The installation of collectors is recommended for efficient solar heating. They are a system of pipelines through which the coolant flows. For protection and better focusing of solar energy, the structure is protected by a transparent glass panel.
To increase the efficient operation of the equipment, it is possible to use various types of coolant in it, which will not change their properties under the influence of negative temperatures. This is important for regions with cold winters.In addition, it is necessary to carefully analyze the offers on the market and choose the optimal design.
Currently, manufacturers offer several ways to organize heating of a private house with solar collectors:
- Vacuum manifolds... The best option for organizing a passive solar heating system. They are characterized by almost complete absence of heat losses;
- Flat collectors... An economical option for solar heating. They are a system of pipes protected by a transparent material. Most often they are used for hot water supply in the summer. Application for combined solar heating requires taking into account the temperature schedule in winter and careful selection of the heat carrier.
The choice is largely determined by preliminary calculations - the required power and the frequency of operation of the heat supply. As an economical option, you can consider the possibility of self-production of flat collectors for heating with solar energy with your own hands.
When choosing a wiring diagram, the area of the structure must be taken into account. She will have a certain windage index.
Vacuum collectors for heating
One of the problems of using solar radiators for heating a house is large heat losses. They are due to the peculiarities of operation - the panel must be located outside the heated room to absorb solar energy. To address this issue, a vacuum solar collector for the heating system has been developed.
The design of the vacuum manifolds consists of an outer casing and an inner glass tube system. For better insulation, the pipelines are separated from the external environment by a vacuum interlayer with rarefied air. In fact, the entire installation is a large transparent thermos.
The specificity of a vacuum solar collector in a heating system is as follows:
- Use of a special liquid with a low boiling threshold as a heat carrier. In this case, there is a more efficient transfer of thermal energy through the heat exchanger to the main heating medium - water;
- Application on the inner surface of a special coating that increases the absorption capacity of thermal solar energy;
- Independence of work from external air temperature.
For the normal functioning of the system, it will be necessary to ensure reliable thermal insulation of the heat exchanger. You should also insulate the pipeline in places where it passes through unheated rooms - an attic, a roofing pie. Standard schemes can be used to calculate the solar collector for heating. But it must be borne in mind that its operation will be ineffective when the temperature of the coolant in the circuit drops to + 22 ° C.
In winter, it is necessary to clean the surface of the collector from the snow cap. Therefore, you need to think in advance of a way to perform this event.
Flat solar collectors for heating
To create a solar heating system for a private house with minimal costs, flat collectors are most often installed. They differ from vacuum ones in their simplified design. However, this increases the requirements for their operation.
The flat collector also has an internal piping system. However, it is made from copper or plastic pipes. For protection, polycarbonate or tempered glass is used. The inner surface is insulated with insulation - mineral wool or foam. Under the influence of sunlight, the tubes are heated and, as a result, the temperature of the coolant rises.
There are severe operating restrictions for a flat solar collector in a heating system:
- Only antifreeze can be used as a coolant.Otherwise, the water will freeze and the pipeline will collapse;
- For better circulation during heat transfer, a pump must be installed;
- At temperatures below -10 ° C, the efficiency of the system drops dramatically.
Due to the latter factor, it is not recommended to organize heat supply of the house with solar energy using flat collectors in regions with low temperatures in winter. Therefore, most often they make a flat solar collector for heating with their own hands for hot water supply in summer, spring or autumn.
Experts recommend making heat supply using solar energy based on flat collectors only in the southern regions of the country with relatively warm winters.
DIY solar collector
It should be noted right away that a do-it-yourself collector will not work to provide heating with solar energy. To do this, you should use the scheme for the production of a vacuum structure discussed above. But at home it is almost impossible to make it due to the lack of the necessary equipment and consumables. Therefore, we will consider one of the simplest ways to make a solar heating battery for hot water supply.
For production, you will need the following consumables:
- Cellular polycarbonate sheet... For hot water supply to a summer cottage or a small house using a solar collector for heating with your own hands, a sheet of 2 * 1 m in size will be enough;
- PVC pipe, fittings and flexible hoses... With their help, a heated water circulation system will be made and supplied to the consumer;
- Frame profile for drywall and foam sheets... They are required to create a protective enclosure in a passive solar heating system.
The honeycomb should be placed horizontally for better water heating. Then longitudinal cuts are made in PVC pipes. Heated water from a polycarbonate sheet will flow through them. A sheet is installed in the resulting cuts. It should not go into the pipe all the way.
With the help of a thermal gun, the seams are insulated. Without this tool, there is a high probability of leaks in the heating and hot water supply of the house with a solar collector. Before installation in the frame, it is imperative to carry out a leakproofness test To do this, fill it with water and visually check for leaks.
For the manufacture of the frame, galvanized drywall profiles are required. They will perform protective functions similar to the body of a solar radiator for heating a summer cottage. A layer of insulation is installed under the polycarbonate sheet, then a self-made solar collector is placed. For more efficient heating, it is recommended to paint the sheet black.
When calculating a solar collector for heating, the position of the sun at a particular moment of the day is taken into account. The greatest efficiency is achieved when the angle of incidence of the rays is strictly perpendicular to the surface of the structure.
The best option is to use solar heating systems for a private house as auxiliary ones. For best efficiency, it is recommended to install a heat accumulator. The water in it will be heated from the collector during the day, and in the dark, the accumulated thermal energy will be transferred to the main coolant in the system.
The video shows an example of making a solar collector from polymer pipes:
