DIY solar oven. How to make a solar oven with your own hands How to make a solar oven with your own hands

Another example of using solar energy for cooking. This time, the author decided to make a solar oven with a wooden structure in order to experience all the benefits of using free solar energy.
With high-quality assembly, an oven of this design can last for many years for cooking in the sun.

1) wooden bars
2) moisture resistant plywood 20 mm thick
3) thin sheets of aluminum
4) metal pins
5) wheels
6) antiseptic
7) paint

Consider the main design features of the solar furnace and the stages of its assembly.

The main advantage of an oven of this design is that in order to monitor cooking, it is not at all necessary to be in the mirror area under the dazzling rays of the sun.

The author decided to make the body of the solar furnace from wood, since it is quite easier to work with it, and besides, the author already had experience working with wood. The body itself was made of wooden beams, connecting which the author received the main frame of the solar furnace. This frame was upholstered with moisture-resistant plywood 20 mm thick, although ordinary boards can also be used. The case itself was made in the shape of a right triangle.

After that, the author covered the inner part of the surface of the solar furnace with thin sheets of aluminum. Cooking will take place due to the transfer of thermal energy received by these sheets of metal, which will be heated under the rays of the sun.

Then the author proceeded to assemble the solar oven, or rather its main cooking chamber. To do this, all the walls upholstered with sheets of thin aluminum were connected in such a way that the entire interior space was upholstered with metal.

As you can see from the pictures, a small hole remains at the back, which will serve as a door. That is, laying food and monitoring its preparation will be carried out through this door located on the back wall of the oven. This way you will be protected from direct sunlight.

The author decided to fix this door with ordinary door hinges. Thanks to this, it will be quite easy and convenient to open it to demonstrate the state of the food, and close it back if the food is not yet cooked.

An important factor in the efficient operation of such a solar oven is that it is constantly turned with its front part under the direct rays of the sun. This will allow the metal sheets to heat up faster.

Further, the author covered the resulting cooking chamber with glass and sealed it. At this stage of assembly, it is important to ensure that there are no targets or holes inside the cooking chamber through which hot air can escape. If such gaps are found, they must be eliminated, as this can seriously affect the efficiency of the oven and the temperature inside the cooking chamber.

In order for the oven to be not on the ground, but at a convenient height level, the author made the legs from wooden beams.

Since the furnace must be turned towards the sun as it moves, small wheels were attached to the bars, which greatly facilitated the task of moving the furnace.

To further increase the efficiency and power of this stove, the author made additional reflectors. These reflectors can be made from mirrors, polished aluminum, or polished stainless steel. In this case, the author decided to make the reflectors in the same way as the inner walls of the oven preparation chamber. that is, the plywood sheets were upholstered with thin aluminum on one side. After that, the reflectors were fixed on all sides of the furnace, this is clearly visible in the picture.

If you do not want the oven to take up a lot of space during storage, then it is reasonable to make the reflectors removable, or, as the author did, folding. To do this, the size of the reflectors was adjusted to the desired frame, and since they turned out to be quite thick 10-20 mm, their fastenings were made at different heights, thus taking into account the thickness when folding.

The potential of solar heat can be used not only to generate electricity at large power plants or to heat housing and utility complexes, but also in the usual household sphere of human activity, for example, for cooking. The very idea of \u200b\u200bcreating a stove that runs exclusively on solar energy is so relevant that craftsmen have long been able to put it into practice. This article will help you make a DIY solar oven with little 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 on an electric stove. However, such a design can be placed next to a barbecue or barbecue, thereby giving newness to your site.

For the manufacture of a solar furnace, inexpensive and commonly available materials are used:

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 furnace from 40x40 bars and plywood. The thicker the plywood, the stronger the structure will be.

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

From roofing iron 0.5 mm. cut out the inside of the furnace (casing). At the same time, we cut the sheet according to the drawing.

After the casing is ready, with the help of nails we nail it inside the casing. Then we process the edges with sandpaper so that there are no burrs.

We install the glass in the frame on a transparent silicone sealant and fix it with glazing beads.

We mount the reflective panel on the hinges.

Do not forget to attach handles for carrying the solar oven and for opening the glass door.

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

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

Glue a mirror on the reflective panel (mirror tiles)

The solar oven is ready to go. The first use of the solar oven, it is necessary to produce without food. Since the paint, in the early days, may give off an unpleasant odor.

Do not forget to treat the oven body with paint, antiseptic, to prevent atmospheric exposure.

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

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

Second production method. Unfortunately, no photos.

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

wooden or metal box
a piece of dark cardboard, preferably black
several pieces of small, black-colored stones
glass according to the size of the box
four pieces of tin as reflectors.

Let's start with the construction of the main frame. It can be welded from metal corners, and it is best to knock it down from bars and boards. Choose the size and shape of the box to your taste, depending on the type and amount of food being cooked. It does not have to be a strictly square or rectangular stove. You can give the design any shape, such as hexagonal, round, and even elliptical. Here, perhaps, everything depends on your imagination and desire to do something unusual and original.

When the box is done, it is necessary to cover the bottom and inner walls with black cardboard or thick paper. The color of the skin must be black, as it absorbs the sun's rays more efficiently. It is necessary to fasten the paper to the box with carnations with a large hat or self-tapping screws with a washer.

Now cut the reflectors out of tin to fit the box, file all sides with sandpaper or a file to remove burrs, and attach four reflectors to the top of the box. This can be done using metal or plastic corners, or simply screw the sheet 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 at any hardware store. With the help of loops, 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, thus ensuring high-quality and fast cooking.

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

Now it remains only to find on your site or elsewhere a few dark stones of medium size and lay them on the bottom of the box. If you come across stones that are too light, try repainting them black and letting them dry completely. What are the stones for? They will be a kind of storage of solar heat. With their help, you can adjust the temperature in the stove, removing or, conversely, placing new stones. Hot stones will allow you to cook dinner even at a time when the Sun is not so bright and warm.

If you want to know exactly what the temperature is inside your "solar oven", don't be too lazy to install a small food thermometer, which can be purchased at any grocery store.

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 it, your oven 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 solar battery, panel (sat)? Essentially, it is a container containing an array of solar cells. Solar cells are the ones that actually do all the work of converting solar energy into electricity. Unfortunately, to obtain power sufficient for practical use, solar cells need a lot. Also, solar cells are VERY fragile. Therefore, they are united in the SB. 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 net for information on homemade SBs and was shocked at how little there was. The fact that few people have made their own solar panels made me think that 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 the construction of the SB is the acquisition of 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 much cheaper
- solar cells of the "second grade" can possibly be used to make a solar battery

When it dawned on me that I could use defective items to make my SB, I set to work. Started by buying items on eBay.

Bought several blocks of monocrystalline solar cells measuring 3x6 inches. To make a SB, it is necessary 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 enough to charge 12V batteries. (Yes, such a high voltage is indeed necessary for efficient charging of 12V batteries). Solar cells of this type are thin as paper, fragile and brittle like glass. They are very easy to damage.

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

I also bought a couple of sets of elements without wax filling from another seller. These items came packaged in a plastic box. They dangled in the box and chipped a little on the sides and corners. Minor chips don't really matter. They will not be able to reduce the power of the element enough to worry about it. The items I bought should be enough to assemble two SBs. I know I might break a couple while reassembling, so I bought a little more.

Solar cells are sold in a wide range of shapes and sizes. You can use larger ones or smaller ones than my 3" x 6". Just remember:
- Cells 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 ones, respectively, less current.
- The total power of your battery is defined as its voltage multiplied by the generated current.

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 deliver the same amount of power. It is also worth noting that using cells of different sizes in the same battery is a 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 work at full capacity.

The solar cells I chose are 3x6 inches and are capable of generating about 3 amps of current. I plan to connect 36 of these elements 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. 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 lamps and small equipment just a few hours after dark. It's just that when I go to sleep, my energy needs are reduced to zero. In short, 60 watts 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, play with, or be eaten by your dog until you're ready to install them in your solar panel. The elements are very fragile. Rough handling will turn your expensive solar cells into little blue shiny and useless shards.

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

Here is a small sketch showing the dimensions of my SB. All measurements are in inches (sorry, metric fans). The 3/4" thick beading goes around the entire plywood sheet. The same side goes in the center and divides the battery into two parts. In general, I decided to do so. 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 so that I include them in my sketches. I always encourage people to experiment and invent their own ideas rather than blindly follow instructions written by me (or anyone 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. Notice the small holes in the sides. This will be the bottom of the battery (the top is at the bottom in the photo). These are ventilation openings 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 must be made in the central dividing bar.

Next, I cut out two pieces of fiberboard that fit the 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 had these on hand. Any thin, rigid, and non-conductive material will do.

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

Oops! In the photo, two sheets of plexiglass are connected on the central partition. I drilled holes around the edge to seat the plexiglass on the screws. Be careful when drilling holes near the plexiglass edge. You will press hard - it will break, which happened to me. In the end, I just glued the broken off piece and drilled a new hole nearby.

After that, I painted all the wooden parts of the solar panel with several coats of paint to protect them from moisture and environmental influences. I painted the box inside and out. When choosing the type of paint and its color, a scientific approach was used. I churned out all the leftover paint I had in the garage and chose one that had enough paint to do the job.

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

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

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

The first step is to "dip" 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 strongly hit the elements one against the other. Boiling water may also be too hot, electrical contacts may be broken in the elements. I also recommend immersing the elements in cold water and then heating them slowly to avoid uneven heating. Plastic tongs and a spatula will help separate the elements once the wax has melted. Try not to pull hard on the metal conductors - they can break. I discovered this when I was trying to separate my elements. It's good that I bought them with a margin.

Here is the final version of the "installation" that 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 hot water. Temperatures in all pots are below the boiling point of water. First, melt the wax in a distant pan, transfer the elements one by one to soapy water to remove wax residues, and then rinse in clean water. Lay items out on a towel to dry. You can change the soapy water and rinse water more often. Just do not drain the used water into the sewer, because. the wax will harden and clog the drain. This process removed virtually all of the wax from the solar cells. Only a few left thin films, but this will not interfere with the soldering and operation of the elements. Washing with solvent will probably remove the wax residue, 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, they became surprisingly difficult to handle and store due to their brittleness. I recommend leaving them in the wax until you are ready to install them in your Sat. This will keep you from breaking them before you can use them. Therefore, 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 set up each element. Then I laid out the elements on this grid with the reverse 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 used to it. Start with just two items. Place the connecting wires of one of them so that they cross the solder points on the back of the other. You also need to make sure that the spacing between the elements matches the markup.

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

I had to repeat soldering until a chain of 6 elements was obtained. I soldered the connecting busbars 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 by 180 degrees with respect to the other two. The orientation of the chains turned out to be correct (the elements are still lying upside down on the substrate). The next step is to glue the elements into place.

Gluing the elements will require some skill. We apply a small drop of silicone sealant in the center of each of the six elements of one chain. After that, turn the chain face up and place the elements according to the markup that was applied earlier. Lightly press down on the elements, pressing in the center to stick them to the base. Difficulties arise mainly when flipping a flexible chain of elements. A second pair of hands won't hurt.

Do not apply too much glue and do not glue the elements anywhere but 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 the element over the entire area, it will break over time. Gluing only in the center allows the elements 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 a copper braid from a cable to connect the first and second chain of elements.

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

Test the first half of the solar battery in the sun. With a weak sun in a haze, this half generates 9.31V. Hooray! Working! Now I need to make another half of the same battery.

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

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

I passed the wire for connecting the halves of the battery 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 solar panel in the system must be provided with a blocking diode in series with the battery. The diode is needed to prevent the discharge of batteries 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 diodes on eBay for just a couple of bucks. I will still have a lot of diodes for my future SBs.

At first I planned to attach a diode outside the battery. But after I looked at the technical characteristics of the diodes, I decided to put them inside the battery. For these diodes, the voltage drop decreases with increasing temperature. There will be a high temperature inside my battery, the diode will work more efficiently. We use some more silicone sealant to secure the diode.

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

It is important to let the sealant dry before we put the plexiglass in place. I recommend based on previous experience. Vapors from silicone can form a film on the inside surfaces of plexiglass and elements if you do not allow the silicone to air dry.

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 connected to the battery charge controller that I use for my wind turbine. Thus, the solar battery will be able to work with it in parallel.

This is what the finished SB looks like with the Plexiglas screen screwed on. Plexiglas is not sealed yet. At first I did not seal the joints. Did a little testing first. According to the results of the tests, I needed access to the insides of the battery, a problem was discovered there. I lost contact on one of the elements. Maybe this happened due to a temperature difference 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 sealant or cover them with an aluminum frame.

Here are the voltage test results of the completed battery in the bright winter sun. The voltmeter shows 18.88V with no load. This is exactly as I expected.

And here is the 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 panel works great!

Solar battery at work. I move it around a couple of times a day to keep it aligned with the sun, but it's not that big of a deal. Perhaps someday I will build an automatic system for tracking the sun.

I made this solar oven for a school project and here are my results and information on how to build it step by step.

1. What is a solar oven?

A solar oven, unlike a conventional oven, is heated using solar thermal energy. Solar ovens can be used to heat food, cook, or pasteurize drinks. There are several types of solar ovens, such as conventional solar ovens, solar panels and parabolic solar ovens. They were first invented in 1767 and are still used in parts of Africa, India and China. Next, I will talk about building such a furnace with my own hands, its advantages and disadvantages.

2. Benefits of solar oven

The solar oven has visible advantages. First, they do not absorb electricity. This may save you some money. Also, solar ovens can be used regardless of location. Secondly, such devices do not harm the environment, since they do not require the use of electricity.

3. Limitations and disadvantages

The main disadvantage of a solar oven is that the heating temperature will depend on the design and the amount of sunlight. Therefore, it should not be used on a cloudy day - the temperature will not reach the required level. In addition, the weather affects its work. During thunderstorms or snow, the efficiency of using the solar oven will be significantly reduced. And finally, the most unpleasant fact - if the solar furnace is built incorrectly, it can quickly break down, or worse, cause burns.

4. Manufacturing process

To create my solar oven, I read the instructions on the Internet beforehand to avoid mistakes.
The first thing I did was spray black paint to attract heat inside a conventional box to attract heat and solar energy. Then I took another box, cut out four identical squares from it and pasted reflective paper (you can use foil). It remains to glue these panels to the top of the main box.
Next, I set up the solar oven using a metal table, and placed a silver frying pan in it. I also lowered a thermometer there, safe for the oven. I tilted the reflective panels a bit so that the hottest spot is in the center.
Now it's time to cook the eggs. I cracked an egg in the pan and closed the top of the four-panel oven. You should also cover the oven tightly with cling film. Thus, the heat inside the box will remain and allow you to cook food.

5. Materials

Scotch.
Reflective sheets (foil).
Several cardboard boxes.
Metal tray or frying pan.
Metal table.
Black paint can.
Food film.
Thermometer.
Egg.
Scissors.
Stationery knife.

7. Photos of the invention process

8. Photos of the cooking process

9. Let's summarize.

At 12:15 pm I started making scrambled eggs. I did not pay attention to the temperature on the thermometer, but at that moment it was about 15 Celsius outside, it was cloudy.
I placed the solar oven in the sun and made sure the reflective panels were pointed there as well.
At 3:31 p.m., the temperature in the oven was 65° Celsius and did not rise above, so the egg was not completely cooked.
In conclusion, I cannot say that the result of this project was successful. I will try to slightly change the design of my oven, for example, you can replace the cling film with a piece of ordinary glass or organic (plexiglass). Since the cling film could move away in some places. In addition, for my experiment, I chose a not entirely successful day - there was no direct sunlight because of the clouds.
I hope this article helped, and if you need to build a solar oven, you will use my advice!

Today, there is an alternative to conventional heat sources - solar energy. A do-it-yourself solar oven is a simple design. In the daytime, the power of this device reaches 1.5 kW, while the heating temperature reaches 150 degrees. The first solar stove was constructed in the second half of the 8th century by Horace de Saussure in Switzerland.

It is known that the flow of heat sent to us by the sun is great, it is a sin to waste so much energy without work. In summer, in the middle lane, it easily reaches one kilowatt per square meter (a kilowatt is, approximately, like an electric stove burner).

Today, this type of mini-kitchen is used in a wide range, from African countries to northern regions, including in our country.

Solar ovens: features and benefits

Such furnaces are varied in size, from a small box to a unit, but are identical in need. Their task is to store heat for any needs. The principle of operation of a solar oven is based on absorbing the thermal energy of sunlight, thanks to which it is possible to cook food without the use of gas and electricity, and keeping it in a heat-insulated chamber. Designs can be purchased at the store, or you can make solar ovens with your own hands.

The design of a solar oven can be easily made from improvised materials.

Advantages of solar oven:

Cheapness of use (does not require fuel).
Cooking safety.
Easy to operate and maintain.
Mobility.
Environmental friendliness.
Possibility of boiling, smoking, baking and frying.
Uniform cooking without the possibility of burning, without the need for stirring.

Types and stages of construction of solar ovens with their own hands

Depending on the type of construction, there are three main types of solar ovens:

Box oven.
Combined ovens.
With mirror concentrator.

The box oven is used for slow cooking in large quantities. This is a cardboard box with a glass or plastic top with reflective mirrors. As a rule, it requires thermal insulation, which can be paper, cardboard, modern heaters. Boxed solar ovens have an advantage in durability: the service life reaches 10 years.

List of materials and tools for building a solar oven with your own hands

The box oven is mainly used for relatively slow cooking of large quantities of food.

1. List of materials:

frame (cardboard, plywood, bars);
glass, mirror;
aluminum foil or metal roofing material;
heat insulator (mineral wool, cardboard, paper, etc.);
paint, antiseptic, silicone;
fasteners (adhesive tape, glue, self-tapping screws, nails, hinges).

2. List of tools:

saw;
scissors, knife;
stapler;
hammer, screwdriver;
brush;
roulette.

DIY step-by-step instructions for making a solar box oven

We are preparing the frame of the device, consisting of 40x40 mm bars (fastener) and plywood sheets (case walls).
We build a frame under the glass.
We fix the finished frame to the furnace frame with the help of hinges.
We sheathe the inside of the future furnace with a metal roofing sheet with self-tapping screws or nails.
We insert the glass into the finished frame, fixing it with glazing beads and treating it with silicone.
We fix the reflective panel with the same hinges on which the mirror or mirror tile is fixed.
We insulate the walls and the base between the frame and the metal sheet with any heat-insulating material, for example, mineral wool, then we cover everything with plywood.
We paint the inner part intended for cooking with dark, preferably black, heat-resistant non-toxic paint.
We treat the outer part with an antiseptic.

Box ovens are very durable designs.

The solar oven is ready for operation. For cooking, you need to put the dishes inside the structure, pointing the reflective panel at the glass. You can also apply the following method of building a box oven:

Build a wooden box.
We line the inside of the box with black thickened paper for maximum absorption of solar radiation.
According to the perimeter of the box, we cut out tin reflectors of identical size, rounding the edges and sanding them.
We fix tin reflectors at the top of the box with hinges, screws or other fasteners, bending at the required angle, in order to accumulate and transfer solar heat to the cooking box.
We construct a glass cover in order to convert ultraviolet into thermal energy.
We lay out stones on the base of the finished furnace - heat accumulators and temperature regulators.
Optionally, install a thermometer.

A stove with a parabolic concentrate is made in the form of a concave mirror, while the sun's rays are absorbed by the focus. Basically, such a kitchen serves to cook a small amount of food in a short time. The main disadvantage of such a furnace is the regular turning of the mirror surface towards the sun, which can cause burns to the mucous eyes and hands.

The combined design of the solar oven consists of a concentrating mirror, including a number of flat mirrors, and a saucepan thermally insulated with polyethylene.

At the first stage, the body for the solar furnace is prepared.

The base of the case is made of a plywood sheet, in the center of which a rod made of aluminum or steel is fixed, about half a meter long. A thread is made at the end of the rod in order to screw the stand.
Grooves are cut for inserting ribs from plywood.
For the manufacture of walls with their own hands, they take four plywood sheets in the shape of a rectangle, cut out on one side with a curved arc, and on the side of fastening with the ribs of the body - with grooves.
The walls are glued to the base and fixed with paper clips.

At the second stage, the mirror of the solar furnace is prepared.

Solar stoves are made of compacted smooth cardboard in the form of triangles.
The triangles are overlapped and on top of the ribs.
We glue the surface of the cardboard with aluminum foil.
A stand for cooking is fixed at a point equal to half the radius of the resulting mirror.

The solar oven is ready. The most optimal material for the box is aluminum. Its advantages are high thermal conductivity and corrosion resistance.

For the manufacture of a solar furnace, inexpensive and commonly available materials are used:

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 furnace from 40x40 bars and plywood. The thicker the plywood, the stronger the structure will be.

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

From roofing iron 0.5 mm. cut out the inside of the furnace (casing). At the same time, we cut the sheet according to the drawing.

After the casing is ready, with the help of nails we nail it inside the casing. Then we process the edges with sandpaper so that there are no burrs.

We install the glass in the frame on a transparent silicone sealant and fix it with glazing beads.

We mount the reflective panel on the hinges.

Do not forget to attach handles for carrying the solar oven and for opening the glass door.

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

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

Glue a mirror on the reflective panel (mirror tiles)

The solar oven is ready to go. The first use of the solar oven, it is necessary to produce without food. Since the paint, in the early days, may give off an unpleasant odor.

Do not forget to treat the oven body with paint, antiseptic, to prevent atmospheric exposure.

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

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

Second production method. Unfortunately, no photos.

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

wooden or metal box
a piece of dark cardboard, preferably black
several pieces of small, black-colored stones
glass according to the size of the box
four pieces of tin as reflectors.

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

If you want to know exactly what the temperature is inside your "solar oven", don't be too lazy to install a small food thermometer, which can be purchased at any grocery store.

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 it, your oven 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.

When it dawned on me that I could use defective items to make my SB, I set to work. Started by buying items on eBay.

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

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

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

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

Test the first half of the solar battery in the sun. With a weak sun in a haze, this half generates 9.31V. Hooray! Working! Now I need to make another half of the same battery.

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

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

And some more sealant to seal the outlet.

Here are the voltage test results of the completed battery in the bright winter sun. The voltmeter shows 18.88V with no load. This is exactly as I expected.