How to cool a greenhouse? As the world progresses towards summer the temperature will continue to rise. Although the primary goal of greenhouses is designed to keep plants cool, extreme temperatures can cause a variety of issues. Insects are more susceptible to attack and diseases, a higher risk of infection decreased yields, and poor yields are only some of the issues extreme temperatures can bring about.
In areas where summer temperatures are particularly extreme, it is crucial to keep the temperature of the greenhouse at desired levels, as not many cultivars thrive in extremely high temperatures. In the past, a variety of techniques have been devised to cool greenhouses by the evaporative cooling method, however, greenhouse designs have also changed to incorporate more passive ventilation.
The ideal scenario is for growers to make use of a mixture of active and passive ventilation to provide the best climate for growing. A balanced strategy that incorporates both active and passive ventilation can help to keep temperatures and costs low.
Which Greenhouse Is It?
The greenhouse is a building that is constructed with roofs and walls, mostly made of transparent materials to trap heat from the sun. We can regulate the temperature as well as other crucial factors such as the presence of pests, humidity, and light. These influences impact the health and growth of plants inside.
We make sure that plants develop healthily and quickly inside the greenhouse, by creating the ideal conditions ( the ideal temperature, humidity, and light) to encourage plant growth.
How Do You Maintain the Temperature of Your Greenhouse?
A greenhouse is an artificially controlled environment that allows plants to develop quickly and remain healthy. Once we’ve mastered the «what» of it, let’s discover the «how»? The basic temperature in a greenhouse can be managed strategically using the following strategies.
- Installing an intake air vent and exhaust vent.
- Using a Shade Cloth.
- In the process of destroying greenhouses.
- Utilizing only exhaust vents.
- making the greenhouse shaded or by using trees being planted within the greenhouse.
Lower Greenhouse Temperatures With Active Ventilation
It is an efficient method of ventilating greenhouses and lower temperatures, however, it will require higher operating costs and more frequent maintenance. In any case, when temperatures in greenhouses are rising and passive ventilation is not able to keep them in check it is vital to have active ventilation.
Fans are the most important method of active air ventilation. They provide a positive heat transfer regardless of the weather by bringing cool air through vents. There’s a broad selection of circulation fans, shutters louvers, and exhausts that are available which allows growers to build the perfect fan set up to fit their particular greenhouse. There are numerous aspects that impact the fan’s performance in circulating air, and it is crucial to take into consideration these before installing any of the equipment.
The first thing to consider is that the fans must be of the right size to circulate air inside the greenhouse. In summer, the fans must provide an air exchange per minute, up to 8 feet in height. It is possible to determine the ideal ventilation rate appropriate to your particular greenhouse, by multiplying the size that your greenhouse by the height that you are using above. In warmer regions, it is recommended to have a height of as high as 10 feet can be utilized.
The location of the fan should be taken into consideration. To allow a system to function to its maximum potential the fan draw distance must be no more than 150 feet. The fans should be placed higher up in the structure to ensure that air is able to flow over the plant canopy.
On the other side of the greenhouse, louvers need to be installed within the wall in order to allow the proper flow of air. It’s also crucial to conduct the proper maintenance on fan systems on a regular basis. Cleaning the fan’s blades, belts, and motors, as well as removing dirt and weeds grass from shutters and louvers are crucial to ensure an extended life for the fan system.
If you want growers who require more cooling power There are alternatives that are more powerful including Evaporative cooling.
Use Large Leaved Plants in Strategic Places…
The plants are nature’s evaporative cooler. The best method to ensure that your greenhouse stays cool is to plant an abundance of plants in your greenhouse, particularly large-leaved plants like the fig trees and this vine. Both are edible, fruit-bearing, soil shading, and evaporative coolers.
The huge leaves shade the soil and help keep the greenhouse cool. In the 33′ Growing Dome, we have approximately 40 tons of earth.
If the 40 tonnes of dirt gets to 110deg or 120deg since it’s just dirt the dome will be much hotter than if there were 40 tonnes of dirt that are 70deg and 80deg.
The plants transpire water by their leaf, and this help to keep the temperature of your greenhouse at a comfortable level. The process of transpiration refers to the procedure of moving water through a plant, and the evaporation of water from leaves stems flowers and leaves. Water is essential for plants but only a small portion of the water that is absorbed by the roots is utilized to grow and for metabolism. The remainder 97-99.5 percent of it is lost to sweating and guttation.
Are you aware of walking or cycling across an unfenced field on a hot afternoon and then swiftly entering the dense forest? The temperature drops immediately by 20 degrees and you get an uplifting blast of humid air flow over your face. This is called transpiration.
Cool Even The Hottest Structures With Evaporative Cooling
Evaporative cooling can be a high and efficient method of cooling the greenhouse. By using heat from the warm air, which evaporates water off plants or pads that are soaked with water or other materials, such systems are able to decrease temperatures by a significant amount. They are also more complicated than other cooling techniques.
They are made up of multiple mechanical parts and require higher utility costs. If an operation requires a substantial cooling capability, there are a few methods for greenhouse cooling that can compete with the use of evaporative cooling.
The cooling pad and fan system is the most popular method of evaporative cooling. The system typically consists of pads made of cellulose, a water pump, a water storage system, and fans. The cellulose padding is then soaked with water pumped via the pump.
The excess water is then pumped and stored in the storage unit. Exhaust fans that are opposite to the pads draw air across the wet surface which evaporates water into the ambient fresh air, cooling the greenhouse. Evaporative cooling is most effective when the relative humidity is low This method is particularly effective in dry areas.
It is essential to correct the size of your pad and fan system to get the most efficient cooling performance. One square foot space is needed for cooling 20 sq ft of floor space. It is also essential to thoroughly clean pads for evaporative cooling. Algae is a quick way to become an issue when using this method and it’s best to select an Evaporative cooling system that’s simple to maintain.
AquaCool Evaporative Cooling Systems are sturdy, user-friendly, and efficient. They come in nine sizes that can be adapted to any application, and customized sizes are also available. AquaCool Systems use cellulose Kuul Pads made from top-quality pure kraft paper to provide the most efficient and efficient cooling through evaporative.
Kuul Pads are durable extremely absorbent and can be easy to clean. Utilizing AquaCool Evaporative Cooling Systems, growers can expect an increase of 16 to 20 degrees in temperature reduction.
If growers require another layer of cooling or better control over light and the photoperiod it is recommended to consider installing an awning system.
The Water Tank
We often talk about how these tanks of water assists in keeping the dome warm during the winter. It can also help to keep it cool during the summer.
The water tank is home to between 600 and 3,000 gallons of water, based on the dimensions of your dome that is cooler than the surrounding temperature. If it were 80°F in your greenhouse, and you put your hand in the pond it would feel a lot warmer than the air surrounding you.
Temperature exchange is easily accomplished via the sheet metal framing inside the tank. The outside temperature can be as low as 90 degrees and trying to reach 100 degrees However, it is the heat mass from 75deg of water that keeps it cool.
The evaporation process also occurs at above the tanks, which helps to create humidity and cool your dome. Its Solar Powered Waterfall upgrade can also help to bring more moisture into the air, particularly with the new spray feature.
Tips: Install an oscillating fan near the pond, or attach a small fan attached to the brace of lumber behind the spitter in order to enhance the cooling evaporative from the tank.
Reduce Cooling Costs With Passive Ventilation
The main benefit of passive air ventilation is the low cost. The initial investment is less than active systems. Once your building is equipped with the features you require that are required, maintenance and utility cost are lower as well.
Passive ventilation is based on two elements that are the wind effect and thermal buoyancy. The term «wind effect» refers to the idea that wind can be seen blowing around buildings, creating small pressure variations around the exterior part of the construction.
The wind is essential for passive ventilation. And speeds of between two and three miles per hour can supply the majority of air circulation. The effect of thermal buoyancy is that cold air lifts hot air toward the uppermost part of the roof. It is a factor that can help air exchange particularly on colder days, but not so when the temperature is high.
The most common passive ventilation techniques are wall and roof vents. Growers who live in areas that have powerful summer winds and plenty of space can take the maximum benefit of vents.
The American Society of Agricultural & Biological Engineers suggests that the vent’s overall area should be 15 % to 20% of the floor. Growers can also personalize their greenhouses with shutters, doors, louvers, and other vents to ensure increased air circulation. A good passive ventilation system makes use of all these options, thus maximizing possible airflow.
Greenhouses constructed that are designed with ventilation passive in mind could benefit from these two principles, decreasing operating costs as well as improving the efficiency of energy. Modern greenhouses are designed to offer maximum ventilation.
Growers should consult professionals to create a structure that maximizes the use of the passive vents available. However, there are instances where passive ventilation isn’t able to offer the required level of cooling. There are fortunately different cooling options to choose from.
Keep The Temperatures Balanced With Curtain Systems
Curtain systems are typically utilized as a complement to different cooling methods. Curtain systems can help reduce heat stress on plants as well as improve the greenhouse’s environment. Additional shade screens reduce the temperature of your greenhouse by reducing the amount of sunlight that can penetrate the structure. The budget alternative is using shade cloths.
Systems for curtains can be utilized either externally or internally, but the shade screen inside is the most common. Curtains that are internal are typically adjustable, allowing growers to choose how much light is allowed into the structure. Growers should consider purchasing curtains made of strong polyolefin films and with the strength of a monofilament yarn.
When selecting a curtain system there are a variety of styles to think about. Gutter-to-gutter curtains use less shade material and form larger bundles when they are retracted. Truss-to-truss systems are the most popular and can be constructed in various ways.
A lot of greenhouses are employing a flat truss-to-truss system because it decreases the size of the greenhouse that has to be cooled. In recent times, greenhouses have begun using a dual-screen system. By the combination of a climate screen and the light deprivation screen, the growers are able to achieve maximum control.
Curtain systems come in various shades, however, the most well-known are white and black. They also come in various shades of shade. The shading gradient is measured in percentages like 30, 60, and 90 percent shade.
While these numbers do show how much light is removed from the structure, it’s crucial to keep in mind that these numbers are not a measure of the reduction in temperature. Selecting the appropriate shade gradient for your crop is vital, and consulting with a professional may assist growers in making the best choice.
Find The Perfect Cooling Solution With The Help Of Growspan
The long-standing tradition of GrowSpan’s top greenhouses and greenhouses has been in place for more than four decades. Growers have faith in GrowSpan to provide them with superior design and structural solutions as well as top-quality greenhouse equipment while providing exceptional customer service.
GrowSpan provides the best greenhouse equipment and is the best option for the horticulture industry. Installation of a cooling system can be a bit complicated, and GrowSpan always provides a Greenhouse Specialist available to help you create the ideal system for your business.
How To Cool A Greenhouse FAQs
What is the cheapest way to cool a greenhouse?
The greenhouse is ventilated is the most efficient and cheapest method to cool the greenhouse. It is recommended to be considered when temperatures in the outdoor air are suitable. Methods are either passive (using fan) or passive. Passive ventilation needs ventilators that can be operated (both intake and vents for outtake).
What is the most effective method of cooling a greenhouse?
Evaporative cooling is an effective, efficient method of cooling the greenhouse. Utilizing heat from the air, it evaporates water off plant pads, pads soaked in water, or other materials, and the systems are able to decrease temperatures by a significant amount.
How do you cool a hot greenhouse?
One of the most effective ways to reduce the heat is to make sure that you supply plants with an adequate flow of fresh air. Ventilation through vents on the roof, side vents (usually louvered), and the greenhouse door can cause the required movement of air to cool overheated plants.