GREENHOUSE HEATING AND COOLING SYSTEMS

Climate control of a greenhouse guarantees reduction in costs and increase in quality and quantity of products, resulting in profitable income.

Greenhouse automated systems provide convenience to control climatic factors as well as control production.  

Our cultivators are not aware that they could achieve a higher income by making difference in tonnage and quality they would derive from an adequately heated or cooled greenhouse.   

No adequate cooling or heating has been achieved in greenhouse cultivation for many years, therefore necessity for climate control has not been totally comprehended because heating and cooling was inadequate.    

This being the case, cultivators are highly unlikely to believe that productivity could be increased by cooling and heating.  

Demand for modern heating and cooling systems is very low because installation of such systems in small family greenhouses would require a very high installation cost.

Installation and operating costs of large scale entities pay for the costs incurred during the year and increase gains.   


The objective of greenhouse cultivation is to ensure minimum 15 C for cultivation to produce forced crops outside the season, and to sell such crops for a fair price so that a profitable production can be achieved.  

To ensure this 15 C in winter time, first an indoor environment with light must be established.

 Costs for Heating

The substantial cost in greenhouse cultivation is the cost for heating. To heat a greenhouse of 10.000 m2 and keep it at 18°C for 7 months from October to April, the amount of natural gas required is 90.000 m3 for Nakhcevan, 26.000 m3 for Antalya, 86.000m3 for Ankara, and 48.000m3 for Baku. There are other types of fuel used for heating in addition to natural gas.

 Types of Fuel

Coal
The cost for heating can be low with cost-efficient coal under conditions of Antalya, however the coal is usually the largest cost item in greenhouse cultivation. But heating with coal becomes less profitable as you go to the north direction from Antalya. Heating with coal would cause loss under conditions of Ankara.

Geothermal
Among possibilities, heating with geothermal resources is the cleanest type of heating that ensures the most profitable production.

Common practice in Turkey:

When it comes to heating of a greenhouse located in southern areas in particular, one might think a wood burning stove is supplied in the greenhouse to break the cold.

This however is very unfavorable and wrong, and in fact, it is like “the cake is not worth the candle” as the idiom says. Disadvantages of such practice can be listed as follows:

Pollination of flowers reduces significantly. Even in some cases, natural pollination (even with bees) could never be achieved. In such case, the cultivator might have to use some hormones. However, even hormones might not achieve a fertilization if the temperature is not adequate.

The crop would be tasteless and flavorless even though a fertilization is somehow achieved. The plant cannot feed its fruit adequately and reach some nutrients to the fruit. Intake of nutrients given through the soil or environment by the plant is insufficient at low temperatures.

Endurance of plants to diseases and pests is very low because the plant is constantly exposed to temperature changes and heated lower than it is required. In this case, cultivators must continuously apply pesticide. This puts a financial burden on cultivators as well as increases the risk for residue on crops

This is naturally an issue that requires a good financial analysis. In cold months, heating higher than +2 C is a large financial burden for entities that don’t have convenient energy resources like geothermal in particular.  

Results:
The temperature ranges 15 to 19 required to make your greenhouse vegetables healthier, more tonnage and more delicious such as tomatoes, eggplants, peppers, squashes, and cucumbers that are commonly cultivated in Turkey. However it should be enough to keep in-greenhouse temperature at 8 to 10 degrees. Grow of vegetables is very slow at lower temperatures; the resistance to diseases reduces, and the cost for pesticides increases. Deformations and spots occur on crops. Crops cultivated address only to the domestic market and are not suitable for exportation.

In greenhouse cultivation, it is a significant problem to keep greenhouses at desirable temperature especially at low temperatures in winter. Because the area to be heated is very large in modern greenhouses, heating is achieved with a heating system that is larger than standard heating systems. Although desired temperature varies depending on the type of vegetables in greenhouse cultivation, it ranges 15 to 20 C. Glass and plastic that are used as cover material for greenhouses are not good at maintaining the temperature. The get warm and cold very quickly. It would be very burdensome to heat a greenhouse to a required temperature where external temperature is 0-5 C. Instead, what we do is to keep the inner ambient temperature at 8-10 C for a certain period of time.  

Modern greenhouses often use a central heating system which includes a boiler and associated piping system. There are two types of materials used for heating systems. They are polyethylene and iron pipes. The useful life of polyethylene pipes varies between 4 and 6 years. Pipes laid inside the greenhouse heat both the soil and the environment. Iron pipes can also be used instead of polyethylene pipes.  

As seen in pictures, the pipes that cover the greenhouse floor as a web heat both the soil and the environment.

In addition to circulation of warm water, heating can be achieved by distributing the heated air, i.e., warm air, inside the greenhouse. Yet, this is not good for vegetables in the long term.

The heating costs of greenhouses depend on the location, type of cover, location direction of greenhouse (e.g., east to west), width of area to be covered, type of the fuel used, and similar factors.

Cooling Costs

Cooling costs increase particularly in southern regions such as Antalya, Mersin, السعودية Saudi Arabia, العراق Iraq, ایران Iran, السودان Sudan, جيبوتي Djibouti, اليمن Yemen, الإمارات العربية المتحدة United Arab Emirates, دُبي Dubai, الكويت Kuwait, الجزائر Algeria, تونس Tunisia, المدينة المنورة Medina, Australia, Hatay, Izmir, جالكاكيو Galkayo, بوساسو‎ Bosaso, where a cooling system is highly needed.  

We offer customers turnkey projects including cooling systems which are designed and implemented by Mayçelik.

Our system reduces the inner temperature of a greenhouse down to 30 C in a short time when the outside temperature is 50 C.

A greenhouse of 10.000 m2 consumes around 10kw/h.