How to make a solar oven. Parabolic solar oven made of cardboard. Box solar ovens

The DIYer decided to do this project to learn a little more about cutting large objects on his new CNC machine. However, he was also motivated by an ongoing interest in both solar energy and hot dogs. It is important to note that the oven will work with any type of food that can be skewered or made cylindrical. If you end up using other types of food, make sure they are completely cooked before eating them.

He originally tried to build this stove out of Styrofoam. After some initial testing, the craftsman discovered that the foam was difficult to cut straight. Foam board crumbles too easily even when using the most sharp knife. The choice was either to make a cutter for foam plastic or use another material. In the end, the master settled on plywood.

Purchased from a local store excellent material for the reflector - an aluminized sheet of paper. Its reflectivity turned out to be high enough for the project to work. If you can't find this material, aluminum foil mounted on cardboard will also work.

The total cost of the product was about $35, including plywood, reflective poster paper, etc.

Tools and materials:
-Plywood;
- Fasteners;
-Aluminum coated paper;
-Loops;
-Wooden skewers;
-Carpentry glue;
-Wood finishing;
-CNC machine with a usable working area of ​​at least 24 (609.6 mm) x 28 inches (711.2);
-Sandpaper;
-Knife;
-Saw;
-Drill;
-Clamps;

Step one: theory
On Earth, the total energy flow (flux density) from the Sun is called the solar constant. The value of the solar constant is approximately 1360 watts per square meter or 1.995 calories per square cm when measured on a surface perpendicular to incident sunlight. This number does not change because the distance between the Earth and the Sun is approximately constant throughout the annual orbit.

The solar oven that the craftsman is building is about 60 cm wide. The parabolic shape of the collector concentrates the energy on the skewer, so the energy for each centimeter of length will be energy that is concentrated at a local 1 cm of width in the collector. IN in this case that works out to 1.991 calories per square cm per minute x 60 cm (width) = 117 calories per minute of solar energy for every cm of length along the skewer.

Detailed scientific measurements -))) have shown that a typical sausage has a diameter of about 2.5 cm. This gives the radius of the sausage about 1.25 cm. The volume of a hot dog or anything else is its length multiplied by its cross-sectional area. The cross-sectional area will be equal to A = Pi times the square of the radius. This means that each linear centimeter of the sausage has a volume of (1.25 x 1.25 x 3.14) = 5 cubic centimeters.

The mass of any object is its density times its volume. According to the manufacturer of the sausages the master used, each sausage weighed 57 grams. With a length of about 12 cm, this gives a volume of about 4.8 g per cm. This results in a sausage density of just under 1 gram per cubic centimeter.

Combining these energy costs per centimeter and mass per centimeter, it turns out that 117 / 4.8 = 24 calories of energy per gram are added to the sausage every minute. Thus, every second we gain enough energy to raise the temperature of the hot dog by about 24 degrees Celsius every minute when its internal temperature is about 20 °C.

But this is true when ideal conditions without loss. Considering losses, the actual net efficiency of the cooker is about 20%, the hot dog's temperature rise and should be about 5 degrees Celsius per minute in bright sunlight. It takes about 15 minutes to heat the sausage to 80°C from an initial temperature of 20°C.

Step two: cutting
The master designed the oven model using the Easel Inventable program. The plywood was then cut using a CNC machine.
Cutting files can be downloaded below.
hotdog.py
sundogger-edited.svg
sundogger.svg
design.svg

Step three: finalizing the details
After cutting, the parts must be separated and processed. The master cuts the joints and grinds problem areas file and sandpaper.

Step Four: Assembly
Now you can start assembling the solar oven.
First, the craftsman assembles the frame. To fix parts, he uses wood glue and furniture screws. After assembling the frame, the master coats it with several layers of shellac.

Now you need to secure the foil paper.

The problem of developing renewable energy sources is becoming more and more urgent every year. Interest in these is constantly growing because they are in many ways unlimited and fossil fuels are finite and expensive. This problem is relevant both globally and in private life.Is it possible to use renewable energy sources in the daily life of a single family? Is it possible using various designs, use solar energy?

In the summer I often go fishing, and the issue of preparing food there is related to lighting a fire, which means finding firewood, preparing the site, not to mention safety precautions. In many places it is often prohibited to light a fire at all. How then to prepare food? In this regard, I am especially interested in the issue of obtaining heat from light energy.The search for answers to the questions posed determined objectives of my research:

Learn what solar energy is and what are the features of its use.

Study the history of the development of solar energy in general and solar thermal energy in particular.

Consider the possibilities of using solar thermal structures (solar ovens).

Design several models of solar ovens.

Conduct an experiment to determine which oven can cook food faster and more efficiently.

Give a presentation and demonstrate the advantages and disadvantages of a solar oven.

Target: make a solar oven yourself at home and demonstrate the results of its work.

Relevance This work is due to the low awareness of schoolchildren about alternative sources energy and the possibility of their use in everyday life.

Hypothesis my research: you can make your own oven powered by solar energy.

An object research – solar oven.

Item research – thermal energy obtained by converting solar energy.

Research methods: studying and collecting information in printed publications, Internet sites; production of solar furnaces of various designs; experiment.

Practical significance my work: as a result of my research, I found out how the sun's energy can be used to generate heat for the purpose of cooking, made several different models of solar ovens and proved that they work effectively, presented the results of my work in a presentation to demonstrate the possibilities of using a solar oven.

Literature review. During my work, I used Internet sources to obtain information about renewable energy sources (7), the possibilities of using solar energy (10, 11, 15), and the history of the development of solar energy (6, 13). Using encyclopedias and physics textbooks, I learned how solar energy is converted into heat (2), what structures are needed to collect solar energy (1, 3). In articles I read about existing solar ovens (5, 12, 14), I learned about how you can make such a oven with your own hands (4, 8, 9). The information found on Wikipedia allowed me to be convinced that the use of a solar oven in Omsk would be possible (16).

THEORETICAL PART

Solar energy and features of its use

One of the main sources of energy is the Sun. Solar energy is the energy of radiation (mostly light) resulting from reactions in the interior of the Sun. Since its reserves are practically inexhaustible (astronomers have calculated that the Sun will “burn” for several more million years), it is classified as a renewable energy resource.

The scope of solar energy is quite extensive, and it is expanding every year. After all, solar energy is relatively cheap, inexhaustible and environmentally friendly. Using just 0.0125% of the Sun's energy could meet all of today's world energy needs, and 0.5% could fully cover future needs.

Solar energy is used to produce electrical, mechanical and thermal energy both on an industrial scale and for private needs.

Solar energy falls on the Earth's surface fairly evenly, without reaching any particular intensity anywhere. For effective use it must be captured, concentrated and converted into a form that can be used for domestic, industrial and transport needs.

Solar collectors are designed for this purpose. They are used for power supply, heat supply (hot water supply, heating), drying of various products and materials, in agriculture, in technological processes in industry.

However, in addition to the undeniable advantages (inexhaustibility and safety for the environment), the use of solar energy has a number of disadvantages. They are presented in Appendix 1. Options for solving these problems are also presented there. Features associated with solar thermal energy (receiving heat from solar energy) are discussed in the following chapters of this work.

History of solar energy development

For a long time, humanity began to use the energy of the Sun to generate heat. According to archaeological data, it is known that ancient people built their homes in places exposed to sunlight.

The ancient Greeks and Romans also tried to use solar energy to light and heat their homes. The ancient Greek playwright Aeschylus wrote that civilized peoples differ from barbarians in that their houses “face the sun.” The Roman writer Pliny the Younger pointed out that his house, located north of Rome, “collected and increased the heat of the sun by the fact that its windows were located so as to catch the rays of the low winter sun.”

In 287 BC. BC, Archimedes constructed a solar cannon using mirrors and shields polished to a shine. According to legend, during the siege of Syracuse by the Roman fleet, the city’s defenders burned enemy ships with this cannon.

In 1839, the Frenchman Alexandre Becquerel discovered the photovoltaic cell. And 44 years later, Charles Fritts designed the first module using solar energy. It is 1883 that is considered to be the year of birth of the era of solar energy. And in 1905, Albert Einstein gave his explanation of this phenomenon from the position quantum theory. In 1921, he was awarded the Nobel Prize for this discovery.

At that time, the use of solar energy to generate electricity and heat was carried out mainly for scientific purposes. The first attempts to use solar energy on a commercial basis date back to the 80s of the twentieth century. In 1989, the American company Loose Industries put into operation a solar-gas station, which demonstrated that gas and the Sun, as the main sources of energy in the near future, can complement each other. At night and in winter, gas provides energy, and in summer and daytime- Sun .

Solar heating has been developed in many countries around the world. In the USA alone, solar collectors with an area of ​​10 million square meters are in use, which provides annual fuel savings of up to 1.5 million tons.

Switzerland has become one of the leaders in the use of solar energy. Approximately 2,600 solar power plants based on silicon photoconverters with a capacity of 1 to 1,000 kW and solar collector devices for generating thermal energy have been built here. The Solar-91 program makes a significant contribution to solving the problem of energy independence for Switzerland, which imports more than 70% of its energy.

In 2010, Russia's first industrial solar station with a capacity of 100 kW was put into operation in the Belgorod region; Projects are being developed for the construction of stations in the Stavropol Territory (Hevel) and the Irkutsk Region (NITOL). However, in general, solar energy is still poorly developed in Russia. The use of solar collectors in Russia is about 0.2 sq.m per 1000 people. For comparison: in Germany 140 sq.m. per 1000 people are used, in Austria 450 sq.m. per 1000 people, in Cyprus about 800 sq.m. per 1000 people

According to the Joint Institute of High Temperatures of the Russian Academy of Sciences, in most of Russia the average daily amount of solar radiation is 4.0-5.0 kWh/sq.m (for comparison: in the south of Spain - 5.5-6.0 kWh/sq.m. m, in the south of Germany - up to 5 kWh/sq.m). That is, indicators comparable to European conditions where solar energy is widespread.

Solar energy has enormous potential in areas such as the Krasnodar Territory, Stavropol Territory, Yakutia, Magadan Region and Siberia. The use of solar energy will be especially useful for regions where connecting to a unified energy system will be too expensive. These regions include areas Eastern Siberia and the Far East, which receive a large number of sunny hours.

Possibility of using solar thermal structures

The subject of research in this work is thermal energy obtained from solar energy, so we will consider the features of its application in more detail.

The conversion of solar energy into thermal energy is ensured due to the ability of atoms of matter to absorb electromagnetic radiation. At the same time, the energy electromagnetic radiation converted to kinetic energy atoms and molecules, that is, in thermal energy. The result of this process is an increase in body temperature.

An example would be stones heated in the sun on a hot sunny day. However, in others weather conditions or in order for the body temperature to reach higher values, it is necessary to catch large quantity sunlight, concentrate them and direct them onto a heated surface. This can be done using solar thermal structures (or solar ovens).

The largest solar oven in the world was built in France in 1970 in the Pyrenees Mountains, at an altitude of 1700 meters, where the air is clean, the sun shines more than 300 days a year and there is very little dust to interfere with the reflection of the sun (Fig. 1).

The largest solar oven in the territory of the former USSR is located in Uzbekistan, about 45 km from Tashkent at an altitude of 1050 meters (Fig. 2).

On the mountainside there are mirrors installed in a checkerboard pattern - heliostats, which reflect the sun's rays onto a concentrator, which is a mirror measuring almost 2000 square meters . The concentrator collects the rays at one point and reflects them into a furnace the height of a nine-story building. The temperature in the oven reaches 3000- 4000 degrees. There are only two solar ovens of this size in the world. They are mainly used for scientific research in the field of metal smelting.

To date, much smaller solar structures have been invented and manufactured. They are intended for industrial use: for heating buildings, heating water, and cooking.

In areas of the Alpine highlands, where it is unprofitable to lay power lines, autonomous solar power plants are being built. They are mounted on the roofs and facades of buildings. One installation occupies approximately 20-30 square meters. It produces enough energy to power the domestic needs of an average Swiss home.

Large companies also install solar power stations on the roofs of production buildings that can cover the enterprise's electricity and heat needs by 50-70%. Thus, solar panels installed by order of Biral on the roof of its production building in Munsingen almost completely cover the technological needs of the enterprise for heat and electricity.

It can be concluded that developed European countries are actively using solar energy to generate electricity and heat for heating buildings. But the use of solar thermal units for cooking is especially important in developing countries, where fuel is very expensive for the vast majority of the population (India, Mali, Kenya, Pakistan), and solar energy is available in abundance.

PRACTICAL PART

Solar oven

The object of study of this work was a device that allows converting solar energy into thermal energy - a solar thermal unit. I was especially interested in the opportunity to make my own small solar oven that can be used in everyday life for cooking.

The relevance of the use of such stoves was confirmed by the results of a competition organized by The Financial Times newspaper and the charitable organization Forum for the Future. Participants presented projects that could have a positive impact on the environment. The winner was the Norwegian inventor Jon Bomer, who proposed simple design solar oven made from a cardboard box and a piece of foil.

The UN Commissioner for Refugees has supported the use of such stoves in the Iridimi refugee camp, where about 18,000 people forced to flee Sudan's Darfur province have taken refuge. There are no local energy sources in this region. As a result of the UN project, refugees received about 15 thousand cardboard solar ovens for cooking. As we can see, the use similar designs relevant all over the world.

Why is it better to cook food in a solar oven? Firstly, it’s convenient: you can put food in a pan, put it in the oven and do other things. Food cooked by the sun will not burn, stick to the dishes or be overcooked. This is especially true on vacation or fishing, when you don’t want to waste time preparing dinner. You just need to periodically turn the stove following the movement of the sun.

Secondly, a solar oven does not require any financial investment. You only need to pay for it once upon purchase or make it yourself from scrap materials. When using a solar stove, you do not have to buy coal and gas cylinders or pay for electricity,

Thirdly, you can cook food outside throughout the summer, thereby keeping your home cooler.

Fourthly, solar ovens do not harm the environment. The air is not polluted by smoke or greenhouse gases. You can cook in such an oven even in parks, where lighting open fires is usually prohibited. The solar oven does not pose any fire hazard.

Fifthly, the solar oven does not depend on electricity, which allows you not to depend on power outages, which often happen, for example, in a summer cottage.

Of course, the solar oven also has a number of disadvantages:

Food in some models of solar ovens is cooked slowly (on the other hand, this can be seen as an advantage, because slowly cooked food contains more vitamins).

A solar oven only works when the Sun is shining.

There are initial costs required to purchase a stove or to manufacture it.

Depending on the type of design, there are three main types of solar furnaces: a box furnace, with a concentrating mirror, and a combined furnace.

I decided to make three types of stoves and compare them with each other - in terms of cost, design complexity and speed of cooking.

Making a box solar oven

Due to its advantages, solar box ovens are the most common type of solar oven. They come in different types: industrially produced and homemade; the shape may resemble a flat suitcase or a wide, low box. There are also stationary ovens made of clay, with a horizontal lid (in tropical and subtropical regions) or inclined (in temperate climates).

The box oven is used for slow cooking in large quantities. This is a box with a glass or plastic top with reflective mirrors. Typically requires thermal insulation.

Such a stove can be made quite simply (from two shoe boxes of different sizes) or a little more complicated, but from more durable materials- made of metal and wood. Examples of box ovens are shown in Fig. 3

Rice. 3. Examples of box solar ovens

I decided to make a box solar oven out of cardboard. For this I needed following materials: two shoe boxes of different sizes, insulation (mineral wool, a piece of polystyrene foam), foil, black film and a piece of glass (Fig. 4).

Rice. 4. Making a box solar oven

I took a large box and lined its bottom with a layer of cotton wool. I covered the inside of the small box with foil and inserted it inside the large box. Then I placed foam insulation between the walls of the boxes. I covered the outside of the large box with black film. The top of the oven is covered with glass, which skips solar radiation into the box and keeps the heat inside.

The outer lid of the box is also covered with foil When folded back, it enhances the incident radiation, and when closed it improves the thermal insulation of the furnace (Fig.).

Rice. 5. Ready-made box solar oven

The cost of manufacturing the stove was 50 rubles (the cost of the foil, other materials did not require financial costs).

Making a solar oven with a concentrator mirror

A concentrating mirror solar oven is a concave mirror that collects the sun's rays. At the focal point of such a mirror is a pan in which food is cooked. The peculiarity of this stove is high temperature heating This is very convenient when you need to quickly cook a small amount of food.

A solar oven with a concentrator mirror can also be made from different materials (cardboard, plastic, wood or metal; foil or a mirror can be a reflective material). You can construct a concentrator mirror yourself, or you can use an old satellite dish or even an umbrella.

Examples of furnaces with a mirror-concentrator are shown in Fig. 6.

Rice. 6. Examples of solar ovens with a concentrator mirror

The main difficulty in making such a mirror is maintaining its parabolic shape. Only in a mirror of this shape will the sun's rays be collected at one point (Fig. 7.).

Rice. 7. Diagram of the incidence and reflection of solar rays in a spherical and parabolic mirror

In addition, you need to correctly calculate the focal point so that the sun's rays fall exactly on the pan. It can be found experimentally. To do this, you need to install the concentrator perpendicular to the sun, bring a piece of wooden board to the center and gradually move it away from the concentrator. The minimum sunspot will be the focal point.

In this case, it is imperative to observe safety precautions, since high energy is concentrated in this place, and the tree can ignite. Therefore it is necessary to use individual means protection ( sunglasses or a welding helmet and leather or canvas gloves).

To make a solar oven with a concentrator mirror, I decided to use a satellite dish because it is designed to collect the sun's rays at a specific point. In addition, I needed a roll of foil (Fig. 8).

Rice. 8. Manufacturing a solar oven with a concentrator mirror

Figure 9 shows a photograph of the oven I ended up with.

Rice. 9. Ready-made solar oven with a concentrator mirror

The cost of manufacturing such a furnace with a concentrator mirror was 300 rubles (250 rubles for the old satellite dish, 50 rub. foil).

Making a combination solar oven

The combination solar oven has a very simple design. It is a mirror-concentrator consisting of several flat reflective surfaces (mirrors or cardboard sheets covered with foil) and a pan, which is thermally insulated from the surrounding air with a plastic bag.

To make such a stove I needed metal foil and cardboard. On cardboard I drew a layout of the future stove (the pattern is given in Appendix 2) and covered it with foil (Fig. 10).

Rice. 10. Making a combination solar oven

The peculiarity of this design is its compactness and mobility. It folds into a compact block measuring 33*33 cm. The diagram for folding the oven is given in Appendix 3.

Figure 11 shows a photograph of the oven that I got.

Rice. 11. Finished combined solar oven

The cost of manufacturing such a stove was 50 rubles. (cost of foil).

The pan used for cooking should be black, since black color absorbs the sun's rays better than others. Most the best option– thin-walled aluminum pan (it heats up quickly and is not subject to corrosion). Because there are no black ones on sale aluminum pans, I decided to smoke them (Fig. 12

Rice. 12. Pots used for cooking in solar ovens

The exact same pan is used in other models of solar ovens. The pan used in the solar combi oven should be placed in a heat-resistant bag for better thermal insulation.

Experiment

One of the objectives of my research was to conduct an experiment to determine which oven would cook food faster and more efficiently.

When conducting an experiment, I decided to cook porridge using all the solar ovens I had made. I decided to prepare the porridge according to the following recipe: 1 glass of water, half a glass of buckwheat, salt (Fig. 13).

Rice. 13. Products needed for the experiment

To conduct the experiment, I chose a sunny day on August 14 (the air temperature on that day was 27 degrees).

First, I boiled the water: installed the stoves, put the pots and poured water into each glass. In an oven with a mirror-concentrator, water boiled after 5 minutes. IN combination oven– in an hour, in a box – in 1 hour 10 minutes. After the water boiled, I added buckwheat (Fig. 14).

Rice. 14. Cooking porridge in various models of solar ovens

In an oven with a mirror-concentrator, the porridge was cooked in 13 minutes (i.e., 18 minutes after the start of the experiment). In the combined oven, the porridge was cooked 50 minutes after adding the cereal (i.e., 1 hour 50 minutes after the start of the experiment). In a box solar oven, the porridge was cooked in 1 hour 10 minutes after adding the cereal (i.e., 2 hours 20 minutes after the start of the experiment).

We can conclude that the fastest is a solar oven with a concentrating mirror. However, I had to turn it after the Sun and observe safety precautions, since the heating temperature at the focal point was very high. The combination and box solar ovens cooked the porridge much later, but it turned out more tasty and crumbly. A solar oven with a mirror concentrator is more bulky and has stricter safety requirements. But it is more reliable than cardboard structures, and food is prepared in it much faster. It can be used to quickly boil water or heat up food in the garden.

All three models of solar ovens can be manufactured and used in various life situations like I did.

CONCLUSION

As a result of the research, I found out that the use of solar energy is relevant all over the world.

In the theoretical part of the study, I learned what solar energy is and examined the features of its use in various areas human life; got acquainted with the history of the development of solar energy; learned the modern possibilities of using solar thermal structures.

In the practical part of the study, I looked at what a solar oven is; learned its advantages and disadvantages; found out what types of designs of household solar ovens there are; I made three models of solar ovens myself from scrap materials; conducted a comparative experiment and was convinced that the use of a solar oven in Omsk is justified and effective.

The practical significance of my research: in the process of studying this topic, I found out how to make a solar oven for cooking with my own hands from scrap materials. At the presentation, I told my classmates about the research and introduced them to the features of the solar stove. I filmed my experiment and posted it on the Internet. I think that demonstrating the ease of use of solar ovens will attract people's attention and encourage them to make a similar oven in order to save non-renewable energy sources.

In the future, I would like to continue my research, study the theoretical foundations of converting solar energy into thermal energy, and learn how to calculate the power of solar furnaces. I am planning to make a solar oven bigger size and use it to heat housing in a summer cottage and heat water for a summer shower.

Use the potential solar heat It is possible not only to generate electricity at large power plants or for heating residential complexes, but also in the ordinary everyday sphere of human activity, for example, for cooking. The very idea of ​​​​creating a stove that runs exclusively on solar energy is so relevant that folk craftsmen have long been able to put it into practice. This article will help you make a solar oven with your own hands, without much effort, so that you can provide yourself and your friends with a delicious hot lunch. The very forces of nature will assist you in this. It is clear that the cooking time in a solar oven will be much longer,than in a conventional oven or electric stove. However, such a structure can be placed next to a barbecue or grill, thereby adding novelty to your area.

Inexpensive and publicly available materials are used to make a solar oven:

Bars;
- plywood 6-10 mm;
- roofing iron 0.5mm (galvanized);
- glass 3-4 mm;
- insulation (mineral wool).
- mirror.

First of all, we make the frame of the solar oven from 40x40 beams and plywood. The thicker the plywood, the stronger the structure will be.

We make a glass frame that is attached to the body using hinges.

From roofing iron 0.5 mm. cut out inner part ovens (casing). At the same time, we cut the sheet according to the drawing.

After the casing is ready, we nail it inside the casing using nails. Then we sand the edges so that there are no burrs.

We install the glass in the frame using transparent silicone sealant and secure it with glazing beads.

We mount the reflective panel on hinges.

Don’t forget to attach handles for carrying the solar oven and for opening the glass door.

We carefully insulate the sides, between the metal casing and the body, and the bottom of the stove with mineral wool. Then we sew up the bottom with plywood.

We paint the metal casing with heat-resistant, matte black paint.

Glue a mirror (mirror tile) onto the reflective panel

The solar oven is ready for use. The first use of the solar oven must be done without food. Because the paint may emit an unpleasant odor in the first days.

Don’t forget to treat the stove body with paint and antiseptic to prevent weathering.

The oven must be placed in direct sunlight. If the sun is low, use a reflector for best results.

For faster cooking, use black cookware, preferably thin aluminum.

Second manufacturing method. Unfortunately, no photos.

So, to build a solar stove we will need the following materials:

1. wooden or metal box
2. a piece of dark cardboard, preferably black
3. several pieces of small, black-painted stones
4. glass according to the size of the box
5. four pieces of tin as reflectors.

Let's start with the construction of the main frame. It can be cooked from metal corners, but it’s best to knock it down from bars and boards. Select the size and shape of the box to your taste, depending on the type and quantity of food being prepared. It should not be a strictly square or rectangular stove. The design can be given any shape, such as hexagonal, round, or even elliptical. Here, perhaps, everything depends on your imagination and desire to do something unusual and original.

When the box is made, you need to cover the bottom and inner walls with black cardboard or thick paper. The color of the cladding must be black, as it absorbs the sun's rays more effectively. The paper must be secured to the box using nails with a large head or self-tapping screws with a washer.

Now cut the tin reflectors to fit the box, sand all sides with sandpaper or a file to remove any burrs, and attach the four reflectors to the top of the box. This can be done using metal or plastic corners, or simply screw the sheet metal with screws and bend it at the required angle to the Sun. It would be more correct to install reflectors on window hinges, which can be bought on the market or in any hardware store. Using the hinges, you can easily adjust the reflectors depending on the position of the Sun in the sky.

Tin reflectors concentrate and redirect the sun's rays into a wooden box, thereby ensuring high-quality and fast cooking.

The last step in making a solar oven is cutting and installing glass, which will perform the main function of absorbing sunlight, which will be converted into thermal energy to heat food. Additionally, the glass acts as a cover for your solar oven.

Now all that remains is to find a few medium-sized dark stones on your site or elsewhere and place them on the bottom of the box. If you come across stones that are too light, try painting them black and letting them dry completely. What are the stones for? They will be a kind of solar heat storage device. With their help, you can regulate the temperature in the stove by removing or, conversely, adding new stones. Hot stones will allow you to start cooking dinner even at a time when the Sun will not be so bright and warm.

If you want to know exactly what the temperature is inside your “solar oven”, take the time to install a small food thermometer, which can be purchased at any grocery supermarket.

The heating time of the solar stove is about 20-30 minutes, depending on the time of day and the amount of solar activity.

That's all, your stove is ready. Enjoy only clean and healthy food!

The simplest design of solar ovens made from cardboard boxes

And now a master class on how to make the solar battery itself.

So what is it solar battery, panel (SB)? It is essentially a container containing an array of solar cells. Solar cells are the things that actually do all the work of converting solar energy into electricity. Unfortunately, to obtain enough power for practical application, you need quite a lot of solar cells. Also, solar cells are VERY fragile. That is why they are united in the Security Council. The battery contains enough cells to produce high power and protects the cells from damage. Doesn't sound too difficult. I'm sure I can do it myself.

I started my project, as usual, by searching the Internet for information on homemade security systems and was shocked at how little there was. The fact that few people made their own solar panels made me think it must be very difficult. The idea was shelved, but I never stopped thinking about it.

After some time, I came to the following conclusions:
- the main obstacle in building a solar system is purchasing solar cells at a reasonable price
- new solar cells are very expensive and difficult to find in normal quantities for any money
- defective and damaged solar cells are available on eBay and other places for much cheaper
- solar cells of “second grade” can possibly be used for manufacturing solar battery

When it dawned on me that I could use defective elements to make my own SB, I got to work. I started by purchasing items on eBay.

I bought several blocks of monocrystalline solar cells measuring 3x6 inches. To make a SB, you need to connect 36 such elements in series. Each element generates about 0.5V. 36 cells connected in series will give us about 18V, which will be sufficient to charge 12V batteries. (Yes, this high voltage is indeed necessary to effectively charge 12V batteries). This type of solar cell is paper thin, brittle and brittle like glass. They are very easy to damage.

The seller of these items dipped sets of 18 pieces. in wax for stabilization and delivery without damage. Wax is headache when removing it. If you have the opportunity, look for parts that are not coated with wax. But remember that they may suffer more damage during transportation. Note that my elements already have soldered wires. Look for elements with already soldered conductors. Even with these elements, you need to be prepared to do a lot of work with the soldering iron. If you buy elements without conductors, get ready to work 2-3 times more with a soldering iron. In short, it is better to overpay for already soldered wires.

I also bought a couple of sets of elements without waxing from another seller. These items came packaged in plastic box. They were hanging around in the box and chipped a little on the sides and corners. Minor chips don't matter much. They won't be able to reduce the power of the element enough to need to worry about it. The elements I purchased should be enough to assemble two SBs. I know I'll probably break a few when putting them together, so I bought a little more.

Solar cells are sold in a wide range of shapes and sizes. You can use larger or smaller ones than my 3x6 inches. Just remember:
- Elements of the same type produce the same voltage regardless of their size. Therefore, to obtain a given voltage, the same number of elements will always be required.
- Larger elements can generate more current, and smaller elements can generate less current.
- The total power of your battery is determined by its voltage multiplied by the current generated.

Using larger cells will allow you to get more power at the same voltage, but the battery will be larger and heavier. Using smaller cells will make the battery smaller and lighter, but will not provide the same power. It is also worth noting that the use of elements in one battery different sizes- bad idea. The reason is that the maximum current generated by your battery will be limited by the current of the smallest cell, and larger cells will not operate at their full capacity.

The solar cells I chose are 3 x 6 inches in size and are capable of generating approximately 3 amps of current. I plan to connect 36 of these cells in series to get a voltage of just over 18 volts. The result should be a battery capable of delivering about 60 watts of power in bright sunlight. It doesn't sound very impressive, but it's still better than nothing. Moreover, this is 60W every day when the sun is shining. This energy will be used to charge the battery, which will be used to power lights and small equipment just a few hours after dark. It's just that when I go to bed, my energy needs are reduced to zero. In short, 60 W is quite enough, especially considering that I have a wind generator that also produces energy when the wind blows.

After you buy your solar cells, store them in a safe place where they won't break, be played with by children, or be eaten by your dog until you are ready to install them in your solar cell. The elements are very fragile. Rough handling will turn your expensive solar cells into little blue, shiny, useless shards.

So, a solar panel is just a shallow box. I started by building such a box. I made it shallow so the sides don't shade the solar cells when the sun shines at an angle. It is made from 3/8" thick plywood with 3/4" thick batten sides. The sides are glued and screwed into place. The battery will contain 36 cells measuring 3x6 inches. I decided to divide them into two groups of 18 pieces. just to make them easier to solder in the future. Hence the central bar in the middle of the drawer.

Here's a little sketch showing the dimensions of my SB. All measurements are in inches (sorry, metric fans). The 3/4″ thick beads go around the entire sheet of plywood. The same side goes in the center and divides the battery into two parts. In general, I decided to do this. But in principle, the dimensions and overall design are not critical. You can freely vary everything in your sketch. I give the dimensions here for those people who constantly whine that I include them in my sketches. I always encourage people to experiment and invent something of their own rather than blindly following instructions written by me (or someone else). Perhaps you can do better.

View of one of the halves of my future battery. This half will house the first group of 18 elements. Note the small holes in the sides. It will be Bottom part batteries (in the photo the top is at the bottom). These are ventilation holes designed to equalize the air pressure inside and outside the SB and serve to remove moisture. These holes should only be at the bottom of the battery, otherwise rain and dew will get inside. The same ventilation holes should be made in the central dividing strip.

Next, I cut out two pieces of fiberboard that were the right size. They will serve as substrates on which solar cells will be assembled. They should fit freely between the sides. It is not necessary to use exactly perforated fiberboard sheets, I just happened to have these on hand. Any thin, hard and non-conductive material will do.

To protect the battery from weather troubles, we cover the front side with plexiglass. These two pieces of plexiglass were cut to completely cover the entire battery. I didn't have one piece big enough. Glass can also be used, but glass breaks. Hail, rocks and flying debris can break the glass and simply bounce off the plexiglass. As you can see, a picture is beginning to emerge of what the solar battery will look like in the end.

Oops! The photo shows two sheets of plexiglass connected on the central partition. I drilled holes around the edge to seat the plexiglass onto the screws. Be careful when drilling holes near the edge of the plexiglass. If you press too hard, it will break, which is what happened to me. In the end, I simply glued the broken piece and drilled a new hole nearby.

After that, I painted all the wooden parts of the solar panel with several layers of paint to protect them from moisture and environmental influences. I painted the box inside and out. A scientific approach was used to select the type of paint and its color. I shook up all the leftover paint I had in my garage and picked out a can that had enough paint to do the job.

The substrates were also painted in several layers on both sides. Make sure you stain everything well, otherwise the wood may warp from moisture. And this can damage solar cells that will be glued to the substrates.

Now that I have the basis for the solar system, it's time to prepare the solar cells.

As I said before, removing wax from solar cells is a real pain. After some trial and error, I finally found a good way. But I still recommend buying the elements from someone who doesn't wax them.

The first step is to "bathe" in hot water to melt the wax and separate the elements from each other. Do not let the water boil, otherwise the steam bubbles will violently hit the elements against each other. Boiling water can also be too hot and electrical contacts in the elements may be broken. I also recommend dipping elements into cold water, and then heat them slowly to avoid uneven heating. Plastic tongs and a spatula will help separate the elements as the wax melts. Try not to pull too hard on the metal conductors - they may break. I discovered this when I tried to split my elements. It's good that I bought them with a reserve.

Here is the final version of the "setup" I used. My friend asked what I was cooking. Imagine her surprise when I answered, “Solar cells.” The first "hot bath" for melting the wax is in the background on the right. In the foreground on the left is hot soapy water, and on the right is clean water. hot water. The temperatures in all pans are below the boiling point of water. First, melt the wax in a distant pan, transfer the elements one by one into soapy water to remove any remaining wax, then rinse in clean water. Place the elements on a towel to dry. You can change the soapy water and rinsing water more often. Just do not pour used water down the drain, because... the wax will harden and clog the drain. This process removed virtually all the wax from the solar cells. Only some have thin films left on them, but this will not interfere with soldering and operation of the elements. Washing with solvent will probably remove any remaining wax, but it can be dangerous and smelly.

Several separated and cleaned solar cells are dried on a towel. Once separated and the protective wax removed, their fragility made them surprisingly difficult to handle and store. I recommend leaving them in the wax until you are ready to install them in your SB. This will prevent you from breaking them before you can use them. So build the base for the battery first. It's time for me to install them.

I started by drawing a grid on each base to make it easier to install each element. Then I laid out the elements on this grid, back side up, so they can be soldered together. All 18 cells for each half of the battery must be connected in series, after which both halves must also be connected in series to obtain the required voltage.

Soldering the elements together is difficult at first, but I quickly got the hang of it. Start with only two elements. Place the connecting wires of one of them so that they intersect the solder points on the back of the other. You also need to make sure that the distance between the elements corresponds to the markings.

I used a low power soldering iron and a solder rod with a rosin core. Also, before soldering, I lubricated the soldering points on the elements with flux using a special pencil. Do not press on the soldering iron! The elements are thin and fragile; if you press hard, they will break. I was sloppy a couple of times and had to throw out a few items.

We had to repeat the soldering until we got a chain of 6 elements. I soldered the connecting bars from the broken elements to the back of the last element of the chain. I made three such chains, repeating the procedure twice more. There are 18 cells in total for the first half of the battery.

Three chains of elements must be connected in series. Therefore, we rotate the middle chain 180 degrees relative to the other two. The orientation of the chains turned out to be correct (the elements are still lying backside up on the substrate). The next step is gluing the elements in place.

Gluing the elements will require some skill. Apply a small drop silicone sealant in the center of each of the six elements of one chain. After this, we turn the chain face up and place the elements according to the markings that we made earlier. Press the pieces lightly, pressing down the center to adhere them to the base. Difficulties arise mainly when turning over a flexible chain of elements. A second pair of hands won't hurt here.

Do not apply too much glue and do not glue the elements anywhere other than the center. The elements and the substrate on which they are mounted will expand, contract, bend and deform with changes in temperature and humidity. If you glue an element over the entire area, it will break over time. Gluing only in the center gives the elements the opportunity to freely deform separately from the base. The elements and the base can be deformed in different ways and the elements will not break.

Here is the fully assembled half of the battery. I used copper braid from the cable to connect the first and second chain of elements.

You can use special buses or even ordinary wires. I just had copper braided cable on hand. We make the same connection with reverse side between the second and third chain of elements. I attached the wire to the base with a drop of sealant so that it would not “walk” or bend.

Test of the first half of the solar battery in the sun. In weak sun and haze, this half generates 9.31V. Hooray! Works! Now I need to make another half of the battery like this.

Once both bases with elements are ready, I can place them in place in the prepared box and connect them.

Each half is placed in its place. I used 4 small screws to secure the base with the cells inside the battery.

I ran the wire to connect the battery halves through one of the ventilation holes in the central side. Here, too, a couple of drops of sealant will help secure the wire in one place and prevent it from dangling inside the battery.

Each a solar panel The system must be equipped with a blocking diode connected in series with the battery. The diode is needed to prevent the batteries from discharging through the battery at night and in cloudy weather. I used a 3.3A Schottky diode. Schottky diodes have a much lower voltage drop than conventional diodes. Accordingly, there will be less power loss on the diode. I bought a set of 25 31DQ03 brand diodes on eBay for just a couple of bucks. I will still have a lot of diodes left for my future SBs.

At first I planned to attach the diode to the outside of the battery. But after I looked specifications diodes, I decided to place them inside the battery. For these diodes, the voltage drop decreases with increasing temperature. The temperature inside my battery will be high, the diode will work more efficiently. Use some more silicone sealant to secure the diode.

I drilled a hole in the bottom of the battery near the top to bring the wires out. The wires are tied in a knot to prevent them from being pulled out of the battery, and are secured with the same sealant.

It is important to let the sealant dry before we secure the plexiglass in place. I advise based on previous experience. Silicone fumes can form a film on the inside surface of the plexiglass and elements if you do not allow the silicone to dry in the open air.

And some more sealant to seal the outlet.

I screwed a two-pin connector onto the output wire. The socket of this connector will be attached to the battery charge controller that I use for my wind generator. Thus, the solar battery can work with it in parallel.

This is what a completed SB looks like with a plexiglass screen attached. The plexiglass is not yet sealed. I didn't seal the joints at first. I did some testing first. Based on the test results, I needed access to the insides of the battery, and a problem was discovered there. The contact on one of my elements has come loose. This may have happened due to temperature changes or due to careless handling of the battery. Who knows? I disassembled the battery and replaced this damaged element. Since then there have been no problems. In the future, I may seal the joints under the plexiglass with caulk or cover them with an aluminum frame.

Here are the results of testing the voltage of the completed battery in bright winter sun. The voltmeter shows 18.88V without load. This is exactly as I expected.

And here is a current test under the same conditions (bright winter sun). The ammeter shows 3.05A - short circuit current. This is just close to the calculated current of the elements. The solar battery works great!

Solar battery in operation. I move it a couple of times a day to maintain orientation to the sun, but it's not that big of a deal. Perhaps someday I will build an automatic sun tracking system.

There are actually several similar structures in the world. Let's start with Solar Furnace in France, that is, from France.

The Solar Furnace in France is designed to generate and concentrate the high temperatures required for various processes.

This is done by capturing the sun's rays and concentrating their energy in one place. The structure is covered with curved mirrors, their radiance is so great that it can be impossible to look at them, to the point of pain in the eyes. This structure was erected in 1970, with the Eastern Pyrenees chosen as the most suitable location. And to this day the Furnace remains the largest in the world.

The array of mirrors functions as a parabolic reflector, and the high temperature regime at the focus itself can reach up to 3500 degrees. Moreover, you can regulate the temperature by changing the angles of the mirrors.

Solar oven using such natural resource Like sunlight, it is considered an indispensable way to obtain high temperatures. And they, in turn, are used for a variety of processes. Thus, the production of hydrogen requires a temperature of 1400 degrees. Test modes for materials carried out in high-temperature conditions include a temperature of 2500 degrees. This is how they are tested spacecraft And nuclear reactors.

So the Solar Oven is not just an amazing building, but also vital and efficient, while it is considered an environmentally friendly and relatively cheap way to achieve high temperatures.

The mirror array acts as a parabolic reflector. The light is focused at one center. And the temperature there can reach temperatures at which steel can be melted.

But the temperature can be adjusted by installing mirrors at different angles.

For example, temperatures around 1400 degrees are used to produce hydrogen. Temperature 2500 degrees - for testing materials in extreme conditions. For example, this is how nuclear reactors and spacecraft are checked. But temperatures up to 3500 degrees are used for the production of nanomaterials.

Solar Oven is an inexpensive, efficient and environmentally friendly way to obtain high temperatures.

In the southwest of France, grapes thrive and all kinds of fruits ripen - it's hot! Among other things, the sun shines here almost 300 days a year, and in terms of the number of clear days these places are second, perhaps, only to the Cote d'Azur. If we characterize the valley near Odeyo from the point of view of physics, then the power light radiation here is 800 watts per 1 square meter. Eight powerful incandescent light bulbs. A little? It’s enough for a piece of basalt to spread into a puddle!

— The solar oven in Odeyo has a capacity of 1 megawatt, and for this it requires almost 3 thousand meters of mirror surface,- says Serge Chauvin, curator of the local solar energy museum. — Moreover, you need to collect light from such a large surface into a focal point with a diameter of a dinner plate.

Opposite the parabolic mirror, heliostats are installed - special mirror plates. There are 63 of them with 180 sections. Each heliostat has its own “point of responsibility”—a sector of the parabola onto which the collected light is reflected. Already on the concave mirror, the rays of the sun are concentrated at the focal point - that same oven. Depending on the intensity of radiation (read: clarity of the sky, time of day and time of year), very different temperatures can be achieved. In theory - up to 3800 degrees Celsius, in reality it turned out to be up to 3600.

— Together with the movement of the sun, heliostats also move across the sky,- Serge Chauvin begins his tour. — Each has an engine installed at the rear, and together they are controlled centrally. It is not necessary to install them in an ideal position - depending on the tasks of the laboratory, the degree at the focal point can be varied.

The solar oven in Odeyo began to be built in the early 60s, and was put into operation already in the 70s. For a long time it remained the only one of its kind on the planet, but in 1987 a copy was erected near Tashkent. Serge Chauvin smiles: “Yes, yes, exactly a copy.”

The Soviet stove, by the way, also remains operational. However, not only experiments are carried out on it, but also some practical tasks are performed. True, the location of the furnace does not allow achieving the same high temperatures as in France - at the focal point, Uzbek scientists manage to obtain less than 3000 degrees.

The parabolic mirror consists of 9000 plates - facets. Each is polished, aluminum coated and slightly concave for better focusing. After the furnace building was built, all the bevels were installed and calibrated by hand - this took three years!

Serge Chauvin leads us to a site not far from the furnace building. Together with us - a group of tourists who arrived in Odeyo by bus - the flow of lovers of scientific exoticism does not dry out. A museum curator set out to demonstrate the hidden potential of solar energy.

- Madame and Monsieur, your attention!— Although Serge looks more like a scientist, he looks more like an actor. — The light emitted by our star allows materials to be instantly heated, ignited and melted.

A solar oven employee lifts an ordinary branch and places it in a large vat with a mirror-like interior. It takes Serge Chauvin a few seconds to find the point of focus, and the stick instantly bursts into flames. Miracles!

While the French grandparents ooh and ahh, the museum worker moves to a free-standing heliostat and moves it just enough so that the reflected rays hit a smaller copy of a parabolic mirror installed right there. This is another visual experiment showing the capabilities of the sun.

- Madame and Monsieur, now we will melt the metal!

Serge Chauvin places a piece of iron in the holder, moves the vice in search of a focal point and, having found it, moves away a short distance.

The sun quickly does its job.

A piece of iron instantly heats up, begins to smoke and even spark, succumbing to the hot rays. In just 10-15 seconds, a hole the size of a 10-cent coin is burned in it.

- Voila!- Serge rejoices.

As we return to the museum building, and French tourists are seated in the cinema hall to watch a scientific film about the work of the solar oven and laboratory, the caretaker tells us interesting things.

— Most often people ask why all this is needed,- Serge Chauvin throws up his hands. — From a scientific point of view, the possibilities of solar energy have been studied and applied where possible in everyday life. But there are tasks that, due to their scale and complexity of execution, require installations similar to this one. For example, how do we model the effect of the sun on the skin of a spacecraft? Or the heating of the descent capsule returning from orbit to Earth?

In a special refractory container installed at the focal point of the solar oven, it is possible to recreate such, without exaggeration, unearthly conditions. It has been calculated, for example, that a cladding element must withstand temperatures of 2500 degrees Celsius - and this can be verified experimentally here at Odeio.

The caretaker leads us around the museum, where various exhibits are installed - participants in numerous experiments carried out in the furnace. The carbon brake disc catches our attention...

- Oh, this thing is from a Formula 1 car wheel,- Serge nods. — Its heating under some conditions is comparable to what we can reproduce in the laboratory.

As mentioned above, the temperature at the focal point can be controlled using heliostats. Depending on the experiments performed, it varies from 1400 to 3500 degrees. The lower limit is necessary for producing hydrogen in the laboratory, the range from 2200 to 3000 is for testing various materials under extreme heat conditions. Finally, above 3000 is the area of ​​work with nanomaterials, ceramics and the creation of new materials.

— The oven in Odeyo does not perform practical tasks,- continues Serge Chauvin. — Unlike our Uzbek colleagues, we do not depend on our own economic activity and we deal exclusively with science. Among our customers are not only scientists, but also a variety of departments, such as defense.

We just stop at a ceramic capsule, which turns out to be the hull of a drone ship.

— The War Ministry built a solar furnace of a smaller diameter for its own practical needs here, in the valley near Odeyo,- says Serge. — It can be seen from some sections of the mountain road. But they still turn to us for scientific experiments.

The caretaker explains the advantages of solar energy over any other when performing scientific tasks.

- First of all, the sun shines for free,- he bends his fingers. — Secondly, mountain air facilitates experiments in a “pure” form - without impurities. Thirdly, sunlight allows materials to be heated much faster than any other installation - for some experiments this is extremely important.

It is curious that the stove can work practically all year round. According to Serge Chauvin, the optimal month for conducting experiments is April.

- But if necessary, the sun will melt a piece of metal for tourists even in January,- the caretaker smiles. — The main thing is that the sky is clear and cloudless.

One of undeniable advantages The very existence of this unique laboratory is its complete openness to tourists. Up to 80 thousand people come here every year, and this does much more to popularize science among adults and children than a school or university.

Font-Romeu-Odeillot is a typical pastoral French town. Its main difference from thousands of the same is the coexistence of the mystery of everyday life and science. Against the background of a 54-meter mirror parabola are mountain dairy cows. And the constant hot sun.

Now let's move on to another building.

Forty-five kilometers from Tashkent, in the Parkent district, in the foothills of the Tien Shan at an altitude of 1050 meters above sea level, there is a unique structure - the so-called Big Solar Furnace (BSP) with a capacity of one thousand kilowatts. It is located on the territory of the Institute of Materials Science NPO “Physics-Sun” of the Academy of Sciences of the Republic of Uzbekistan. There are only two such ovens in the world, the second is in France.

The BSP was put into operation under the Soviet Union in 1987,” says Mirzasultan Mamatkasymov, scientific secretary of the Institute of Materials Science NPO Physics-Sun, Candidate of Technical Sciences. — Sufficient funds are allocated from the state budget to preserve this unique object. Two laboratories of the institute are located here, four are in Tashkent, where the main scientific base is located, where the chemical and physical properties of new materials are studied. We carry out the process of their synthesis. We experiment with these materials by observing the melting process at different temperatures.

The BSP is a complex optical-mechanical complex with automatic control systems. The complex consists of a heliostat field located on the mountainside that directs the sun's rays into a paraboloid concentrator, which is a giant concave mirror. At the focus of this mirror, the highest temperature is created - 3000 degrees Celsius!

The heliostat field consists of sixty-two heliostats arranged in a checkerboard pattern. They provide mirror surface concentrator with luminous flux in the mode of continuous tracking of the Sun throughout the day. Each heliostat, measuring seven and a half by six and a half meters, consists of 195 flat mirror elements called "facets". The reflective area of ​​the heliostat field is 3022 square meters.

The concentrator, to which the heliostats direct the sun's rays, is a cyclopean structure forty-five meters high and fifty-four meters wide.

It should be noted that the advantage of solar ovens, compared to other types of ovens, is the instantaneous achievement of high temperatures, allowing clean materials without impurities (thanks also to the purity of the mountain air). They are used for oil and gas, textile and a number of other industries.

Mirrors have a certain service life and sooner or later fail. In our workshops we produce new mirrors, which we install to replace the old ones. There are 10,700 of them in the concentrator alone, and 12,090 in the heliostats. The process of making mirrors takes place in vacuum installations, where aluminum is sprayed onto the surface of used mirrors.

Fergana.Ru:- How do you solve the problem of finding specialists, since after the collapse of the Union there was an outflow of them abroad?

Mirzasultan Mamatkasymov:- At the time the installation was launched in 1987, specialists from Russia and Ukraine worked here and trained our people. Thanks to our experience, we now have the opportunity to train specialists in this field ourselves. Young people come to us from the Faculty of Physics of the National University of Uzbekistan. After graduating from university, I myself have been working here since 1991.

Fergana.Ru:- When you look at it grandiose building, the openwork metal structures, as if floating in the air and at the same time supporting the “armor” of the concentrator, bring to mind frames of science fiction films...

Mirzasultan Mamatkasymov:- Well, in my time to shoot science fiction, using these unique “scenery”, no one has tried here yet. True, Uzbek pop stars came to film their videos.

Mirzasultan Mamatkasymov:- Today we will melt briquettes pressed from powdered aluminum oxide, the melting point of which is 2500 degrees Celsius. During the melting process, the material flows down an inclined plane and drips into a special tray, where granules are formed. They are sent to a ceramic workshop located near the BSP, where they are crushed and used to make various ceramic products, ranging from small thread feeders for the textile industry to hollow ceramic balls that look like billiard balls. Balls are used in the oil and gas industry as floats. At the same time, evaporation from the surface of petroleum products stored in large containers at oil depots is reduced by 15-20 percent. In recent years, we have manufactured about six hundred thousand of these floats.

We produce insulators and other products for the electrical industry. They differ increased wear resistance and strength. In addition to aluminum oxide, we also use a more refractory material - zirconium oxide with a melting point of 2700 degrees Celsius.

The smelting process is monitored by a so-called “technical vision system”, which is equipped with two special television cameras. One of them directly transfers the image to a separate monitor, the other to a computer. The system allows you to both observe the melting process and carry out various measurements.

It should be added that the BSP is also used as a universal astrophysical instrument, opening up the possibility of studying the starry sky at night.

In addition to the above work, the institute pays great attention to the production of medical equipment based on functional ceramics (sterilizers), abrasive instruments, dryers and much more. Such equipment has been successfully introduced into medical institutions in our republic, as well as into similar institutions in Malaysia, Germany, Georgia and Russia.

At the same time, solar installations were developed at the institute low power. For example, the institute’s scientists created solar furnaces with a capacity of one and a half kilowatts, which were installed on the territory of the Tabbin Institute of Metallurgy (Egypt) and at the International Metallurgical Center in Hyderabad (India).

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And here's more on this topic . Of course, let’s also remember in general about . Oh yes, but you know

It is unlikely that anyone can be surprised now by how solar energy works on Earth. The sun supplies us with electricity, heats our homes, gives life to our electronic devices. And the further, the more solar energy enters everyday life, gaining more and more new positions.

And no one can be surprised now wristwatch solar-powered, calculators, flashlights, receivers, mobile phones powered by solar panels. When hiking, on vacation, or at the dacha, solar panels are an irreplaceable thing. Nowadays, country houses and cottages are being built, which are completely “solar powered” and do not depend on general energy networks.

Country house with solar heating and electricity

The sun gives electricity to these houses, the sun heats them, illuminates the garden near the house, the street. This electricity is enough to keep everything working Appliances In the house there is a refrigerator, TV, vacuum cleaner, washing machine, electric oven. But it's in the house. What about outside the house? fresh air? In the summer it is much more pleasant to dine on the veranda, in the gazebo. You can, of course, cook food at home. And then carry it to the table. Or you can put a solar oven next to the veranda or gazebo and cook everything on the spot. And, as they say, piping hot, straight to the table.

Solar oven on a summer cottage

The good thing about a solar oven is that it does not take up much space and is easy to assemble and install. It does not require any fuel, does not pollute the environment, and folds up easily after use. This is an indispensable thing for the country house, for going out of town for a picnic, or for hiking. These ovens can be of different sizes, different designs, folding and stationary, but they always have the same principle - to collect the sun's rays in a beam and direct them to where the container in which food is cooked will be located. And how this beam of solar energy is used largely depends on the design of the furnace.

What is a solar oven?

Back in 1956, the first solar oven appeared in the USSR. A parabolic mirror focused the rays of the sun onto a special stand on which a vessel with water was installed. After a short period of time, the water began to boil. Journalists photographed this miracle of technology from all angles, several short notices appeared in the press, and that was the end of the matter. Industrial production of such devices was then abandoned.

But craftsmen, unlike industry, accepted the new product with enthusiasm. They began to modernize it, new ones appeared Constructive decisions, many homemade devices. These were already verified parabolic mirrors, nose rotating mechanisms, which made it possible to rotate the mirror following the sun without changing the location of the cooking container. These were also solar ovens made from scrap materials - wood, cardboard, tin. There were more complex designs, combining a traditional mirror concentrator and oven.

Solar oven

All of these devices were lightweight, compact, and easy to assemble and disassemble. They took up very little space in backpacks and did not require any fuel. That’s why they were so willing to take them on hikes and to various country picnics. After using them, there was no ash, no coals, nothing left. And you could cook anything you wanted on these stoves. From simple boiling water to fish soup, kebabs, barbecue.

DIY solar oven

Making your own solar oven is not particularly difficult. Usually, when starting manufacturing, they are guided only by what this structure is actually being built for. And the question of how to make a solar oven is not worth it at all. If we are talking about installing such a stove in the country, in a cozy place near country house, then here you can think about building a solid, stationary structure. For hiking, you can use a lightweight collapsible design. A somewhat more complex, but also collapsible installation can be made if you plan to drive out of town for a picnic.

The simplest solar oven is assembled by craftsmen from an umbrella. On an open umbrella with inside a mirror film or just aluminum foil is glued on. It is advisable to remove the umbrella handle. And the oven is ready.

All that remains is to stick a stand for a pot, kettle, pan into the ground, fix an improvised mirror nearby, and focus the beam of light on the place where the container with the food being prepared will be located. And the oven is ready. Some craftsmen cover the inner surface of the umbrella with a mosaic of mirrors. But this makes the structure much heavier, making it practically non-removable or disposable.

Umbrella solar oven

For a more complex design you will need a not very large one. cardboard box(about half a meter on each side), four wooden blocks equal in length to the height of the box, with a cross-section of 25x25 mm, glass having dimensions equal to the sides of the box.

You will also need heat-resistant black paint (necessarily non-toxic!), several bricks (as many will fit on the bottom of the box), mirror film or aluminum foil. Paint the inside of the box with black paint. Paint the bricks with the same paint. Can be painted in two layers.

Leave for some time so that the paint dries well and the smell disappears from the box. Glue on the four upper wings of the box mirror film or foil. Strengthen the corners of the box wooden blocks. They will hold the glass. Place bricks on the bottom of the box. Now all that remains is to put it in a place that receives maximum sunlight. The oven is ready for use.

Solar oven made from cardboard boxes

You can place a saucepan, kettle, or frying pan on the bricks. Orient the mirror coverings of the box so that the maximum amount of sunlight gets inside, cover the box with glass and wait for the food to cook. Temperatures inside the box may exceed 200°C. Bricks, when heated, retain heat if the sun suddenly disappears behind the clouds.

Industrial solar ovens

As for solar ovens produced by industry, their creators have already given free rein to their imagination, equipping these devices with all imaginable and inconceivable devices. Lightweight, folding like a suitcase, they can be installed in a matter of minutes. working position. These furnaces combine the advantages of solar parabolic concentrators and vacuum tubes.

Solar Stove

At the focus of a parabolic cylindrical mirror there is a long vacuum tube. But instead of a low-boiling liquid, there is a tray in the inner cavity into which food products are placed for cooking. The tray is inserted into the tube and fixed. The vacuum around the internal cavity provides reliable thermal insulation and high temperatures inside it. The temperature in the internal cavity can exceed 300°C.

Vacuum pipe with adjustment screen

In order to control the temperature in the working chamber, a thermometer is installed at the end of the vacuum tube. He is integral part electronic control unit. This unit has a thermostat with preset operating temperature, a mirror rotation control system, a timer that closes the mirror after a specified time and sounds a sound signal. All electronics are powered by a solar panel built into the housing.

Thermometer with thermostat and adjustment controls

When assembled, this stove looks like a suitcase approximately 75 cm long, about 40 cm high, 11 cm thick. It weighs a little over four kilograms. And you can cook anything in it: meat, fish, vegetables. You can bake pies. And of course, its most important advantage is that it is an absolutely environmentally friendly device that does not consume any other energy except the energy of the sun and does not pollute the environment.

Solar oven assembled and loaded with food for cooking

Of course, it would be naive to believe that helium furnaces can fully replace traditional gas and electric ones. But on campaigns, on summer cottages, at country picnics they successfully displace old bulky devices, which also require fuel, and leave behind heaps of ash and smoked dishes. Environmentally friendly, sparkling mirror solar ovens confidently take their place in our daily lives.