- Trench greenhouses by Vladimir Antropov
- Eco greenhouse
- Vegetarian Ivanov
- Solar greenhouses with heat accumulators
Antropov’s trench greenhouses, Ivanov’s vegetarian, eco greenhouse, solar greenhouses with heat accumulators. In this article, we will consider the features of the device and the advantages of these unique structures..
Greenhouses are structures that significantly extend the growing time of various crops. They are needed everywhere. In the northern regions, it is important not to miss a single warm day, and each degree of heat saved is of the greatest importance – after all, when growing vegetables, it is necessary to keep within a very short time. In the southern regions, the greenhouse will help to cultivate plants almost all year round..
Unfortunately, the traditional structures that can be found on almost every personal plot have three main drawbacks:
- At the time of low standing of the sun, and it happens in the morning and in the evening in spring, autumn and winter, its rays are reflected at sharp angles very strongly, as a result of which only 25-30 percent of solar energy can penetrate into the greenhouse.
- In the cold season, it is quite difficult to store and save heat due to large losses through the greenhouse cover, which leads to huge jumps in day and night temperatures – and this has an extremely negative effect on the development and fruiting of crops.
- Traditional greenhouses have direct ventilation in the form of all kinds of vents, doors, and the like. And it is through it that all that is so necessary for plants for normal growth, carbon dioxide, nitrogen and almost all the moisture evaporated by crops. This is why greenhouse beds need constant watering and fertilization..
The unique greenhouse principles discussed below help solve all these problems..
Trench greenhouses by Vladimir Antropov
The name speaks for itself. The basis of such a heifer is a trench with a depth of one and a half meters or more (it all depends on how deep the groundwater is located on the site), the length is arbitrary, the width is from two meters. On the sides of the trench, brick retaining walls are arranged, which serve as a wonderful heat accumulator. For growing plants, high beds made of bricks are used here – for a detailed description of their design, see the article “Organic farming. How to create smart beds ”. Their main advantage in this case is that they actively accumulate heat during the day and gradually release it at night..
From above, the trench greenhouse is covered with a simple arched structure of plastic pipes bent by an arc. The pipes are placed at intervals of 1.2 meters and are fastened together with crossbars. The plastic wrap is stretched in the following way: one edge of the strip is attached to the rail and dragged with two ropes to the other side. After that, the edges of the film are pressed against the base of the greenhouse with wooden slats using dowels. In order for the film to hold better, it is pressed to the structure with ropes thrown over and well stretched between the frame pipes.
Doors located almost under the ceiling at both ends act as vents in Antropov’s trench greenhouses. Brick beds are made of such a height that their surface is located under the ridge of the greenhouse – this is the place that is a zone of stable accumulation of warm air. With this arrangement, there is no negative effect of cold air on plants – it smoothly flows down to the floor.
The advantages of a trench greenhouse of this design are obvious. Firstly, heat losses are significantly reduced in Antropov’s greenhouses, and the high temperature remains here for a long time. This is due to the fact that brick props and high beds quickly warm up and accumulate a large amount of heat. In addition, in winter, the deep soil horizon gives off heat by itself. The relatively small volume and minimal wind blowing area contribute to instant warming of the air. As a result, the night temperature in such a greenhouse in winter is 8-12 degrees higher than in the usual one. I would like to note that heating is not used here at all. And on the coldest nights, in order to protect plants from frost, it is enough just to cover the beds with non-woven covering material..
Another important advantage of Antropov’s trench greenhouses is that the air temperature changes smoothly here. The surface of heat exchange through the walls of the beds is three times larger than through the soil. Considering that the brick perfectly retains heat, a kind of thermal flywheel is obtained, that is, the excess heat is absorbed for a long time, and its deficiency is compensated for for a long time. The air in such structures does not overheat until mid-June.
The author of the idea is American farmer Anna Edei. When organizing the eco-greenhouse, Anna used the ideas of the founders of the permaculture movement, based on the mutual adaptation of all members of a certain ecosystem to each other. We talked in detail about permaculture in the article “Organic farming. Permaculture – life in harmony with nature “.
The area of the eco-greenhouse built by Anna Edei is 300 sq. m. The structure is elongated in the direction from east to west. The vertical north wall is covered with white plastic and acts as a reflector of the sun’s rays. The roof is flat and sloping south. The side walls are made of fiberglass, and the roof is covered with sagein (reliable transparent heat insulator), special attention is paid to tightness – all this ensures minimal heat loss.
But the main highlight of the eco-greenhouse is its symbiosis with animals. At both ends of the structure there are premises for their maintenance – on the one side, a rabbit house, in which 30–40 rabbits live, on the other, a chicken coop for 60–70 chickens. These rooms are also very light and airtight. The eco-greenhouse has a special system of perforated pipes laid underground through which warm air from the menageries is pumped into the greenhouse with the help of a fan. And along with this air – heat, ammonia, carbon dioxide and moisture. As a result, everyone is good – the air in the hen house and rabbit house is cleaned, feeding and thereby heating the plants in the greenhouse.
The composition of the soil in the eco-greenhouse is as follows: sod land, sand, compost made from chicken and rabbit droppings, ash. A well-organized subsoil drip irrigation system creates ideal conditions for plants, after collecting all waste goes to the animals living nearby.
Anna Edei calculated that each “animal” gives as much heat in a year as can be obtained from 10 liters of oil – savings on heating reach 7 thousand dollars a year.
Among other things, a large amount of heat in an eco-greenhouse is accumulated in the water. The total volume of installed water tanks is about 16 tons, and special fans are mounted under the ceiling, powered by solar panels and automatically turned on in sunny weather. They drive hot air down onto containers of water, fenced off from the beds with plants by a curtain during the day. During the day, these so-called radiators absorb a huge amount of heat, which they give off at night. All water reservoirs are interconnected by pipes so that with the help of a pump warm water from above is distilled downwards – thus the entire volume is heated evenly.
In the summer heat, specially thought-out ventilation saves the plants from overheating in the eco-greenhouse. On the south side, the transoms are located right next to the ground, and on the north – almost under the ceiling. This allows hot air to slide up the ramp and quickly escape. Tanks with water effectively smooth out the temperature difference, at night they give off daytime heat, and during the day – night coolness, so ventilation is used only on very hot days.
This unique principle of a greenhouse was developed and patented by the Kiev physics teacher Alexander Vasilyevich Ivanov back in the 50s of the last century. The design of the vegetarian is thought out to the smallest detail and eliminates all three main problems of traditional greenhouses, which we talked about at the very beginning – lack of sunlight, heat loss through the cover, loss of carbon dioxide, moisture and nitrogen as a result of direct ventilation. Let’s talk about everything in order.
It is necessary to build a vegetation on a slope (15–20 degrees). The slope can be natural or loose, but always slope to the southeast or south sides. The approximate size of the building: length 5m, width 4m, height 1.7-2m. The flat roof and three walls are made of glass or cellular polycarbonate, the latter being almost ideal for this structure.
The back wall is solid. This can be a suitable wall of a house or any utility room, whitewashed with lime, painted with white paint, and ideally covered with a mirror film. It acts as a reflector that doubles the sun’s rays on the soil..
Thus, a slope of 15-20 degrees, a flat roof and a reflective wall in winter significantly increase the penetration of sunlight, and the lower the sun, the more powerful the effect..
The problems of loss of heat, carbon dioxide and nitrogen are solved thanks to an interesting invention, which is a closed cycle of heat and air exchange. Plastic pipes are buried into the ground to a depth of 35–40 cm, located at a distance of 60–65 cm from each other throughout the entire area of the greenhouse. Their lower (southern) ends are removed from the soil and covered with a fine mesh (so as not to get debris). The upper (northern) ones are connected into a transverse collector, from which a riser (vertical pipe) is laid out in the main wall. The riser does not go out directly, but through a special control chamber, which opens into the vegetarian at a height of about one and a half meters. Both above and below this chamber is limited by dampers, and at the exit to the greenhouse there is an ordinary household fan with a power of 15–20 W. This power is quite enough for 3-4 pipes, the diameter of which is 7-10 cm. If there are more pipes, then it is necessary to mount another riser with a fan.
During the day, in sunny weather, the temperature inside the greenhouse is 30–35 degrees (even in winter). The upper damper of the control chamber closes, the fan turns on and sucks in warm air, driving it through pipes into the soil. At the same time, the soil warms up, and the cooled air is blown back out and heats up again. As a result, the earth warms up to a temperature of 30 degrees for the whole day and becomes a natural accumulator of heat, which lasts all night. At night, a fan drives heat from the soil into the air.
A similar system is widely used in many European countries, especially in Scandinavia, heat accumulators here are not only the soil, but also stone walls, collectors inside pools, stone floors.
Practice shows that if everything is in order with tightness, such a closed heat exchange cycle gives excellent performance in winter without any heating. If in winter it is minus 10 in the daytime, in vegetation – plus 18, at night temperatures of minus 15 in vegetation – plus 12. In the case of very severe frosts, an ordinary not very powerful heater (1–1.2 kW) is inserted into the control chamber, with the help of which warm air is driven in.
In spring and cool summer, a closed cycle in the same mode protects the greenhouse from overheating – at night, the soil no longer accumulates heat, but coolness, which cools the air during the day.
In hot summertime, this heat exchange system perfectly removes excess heat outside. The lower flap of the chamber closes, and the upper one opens – the fan simply expels hot air from the vegetarian outside, but carbon dioxide is also lost, therefore, it is recommended to use such ventilation only in case of emergency. It is the closed system of heat and air exchange that accumulates the amount of CO necessary for normal growth and development inside the greenhouse.2 and nitrogen.
The system of perforated pipes, buried in the soil of vegetation, in a closed cycle, allows to solve the problem of loss of air and soil moisture. Such a system itself is an effective condensate collector..
When warm air passes through cool pipes, it gives off a lot of water, which falls as condensation on the walls. Pipes – perforated (holes with a diameter of a pencil are punched every 20 centimeters along their entire bottom), laid on a thin layer of crushed stone or expanded clay, which allows water to freely pass into the soil.
So, when the closed system of heat and air exchange is turned on, the water that is evaporated by plants and soil is forcibly returned back to the roots. Warm soil is moistened with warm water – nothing better for plants can be thought of. In the hot season, when it becomes necessary to use open ventilation, and there is a lack of moisture, a drip irrigation system is used in vegetation.
Another very important point is that the fan mounted in the control chamber is equipped with the simplest temperature sensors. The entire system turns off automatically when the air temperature in the underground pipes and in the general array of the greenhouse equalizes.
Ivanov’s Vegetarian is not just a greenhouse. This capital unique structure is considered an example of technology for the rational use of solar energy. If the temperature outside does not drop below -10 degrees below zero, no heating, except for the sun’s rays, will be required. Agronomists, who have learned the effectiveness of such a greenhouse in practice, say that the costs of maintaining the required microclimate in a vegetarian are 60–80 times less than in a conventional traditional greenhouse. Vegetarian pays off in the first year, despite the need for capital construction.
Solar greenhouses with heat accumulators
As we have already found out, one of the main problems of traditional greenhouses is the huge heat loss through the outer cover. Therefore, if you want to grow vegetables in a regular greenhouse during the cold season, you need to take care of heating and proper thermal insulation. This is described in detail in the article “Electric heating of a greenhouse – choosing the optimal heating system”.
You can save on heating by using the design of the so-called solar greenhouse (solar greenhouse), equipped with reliable heat accumulators. The design of such greenhouses resembles the Ivanov’s vegetarian described above. That is, one solid wall, covered with a reflective material, the roof and walls are made of reliable material (cellular polycarbonate or double glazing is best suited), which effectively reduces heat loss.
The main highlight of solar greenhouses is a subsoil heat accumulator, organized as follows. Based on a greenhouse area of 100 sq. m, a hole is dug in the middle, 1 meter wide, 15 meters long and 1.2-1.4 meters deep, which is filled with pieces of granite or broken brick with a fraction of 150-200 mm. Brick channels are made along the entire length, coming out through plastic pipes with a diameter of 350 mm. On one side, a 0.1 kW fan is installed in a brick channel. During the day, the battery is charged with heat, which serves as heating at night.
So, we examined the unique principles of greenhouse design, which help maintain an optimal microclimate for growing plants at no extra cost. Having built such structures, you will be able to grow vegetables almost all year round, which will provide your family not only with fresh vegetables and herbs, but also get the opportunity to organize an additional or main very profitable business, especially in winter..