The Most Efficient Greenhouse Dehumidifier – How to Compare Dehumidifiers

One of the most important metrics when comparing dehumidifiers, is energy efficiency. Using the most energetically efficient greenhouse dehumidifier optimizes climate conditions, increases yields and quality, and saves energy and money.

Choosing the right, most efficient greenhouse dehumidifier for your needs isn’t easy, and there’s a lot to consider.

The following is a breakdown of what’s important to consider when it comes to measuring greenhouse dehumidification efficiency, and how you should choose the right dehumidifier for your greenhouse:

Dehumidifier Efficiency Is Measured in Water Extraction per kWh

Using the right dehumidifier saves a lot of energy. But to determine just how much energy a greenhouse dehumidifier can save you need to know its energy efficiency.

There’s a simple way to calculate energy efficiency. Just divide the amount of water a dehumidifier extracts by the amount of energy it uses. DryGair, for example, extracts 45 liters per hour, running on 10 kW – 4.5 liters per kWh.

Of course, if you use other energy sources, such as gas, or if you connect the dehumidifier to a heating system, you must take them all into account. This is even more important to consider at times such as these, when energy prices are rising.

This measurement is the most basic way to determine how efficient a greenhouse dehumidifier is. But there are more factors to consider before choosing the right one for you.

 

 

An Efficient Greenhouse Dehumidifier Is Designed for Greenhouse Conditions

Some dehumidifiers, marketed as greenhouse humidity control solutions, aren’t really made for horticulture. Rather, they’re designed for various industrial needs. So, while they may be powerful, or boast a large treatment capacity, they’re actually far from optimal for greenhouse use.

Greenhouse growers should opt for dehumidifiers that presents design conditions similar to those of a greenhouse.

For example, a dehumidifier that presents an extraction rate of 50 liters per hour, at 26°C, or at 100% relative humidity, won’t be able to reach these results in a greenhouse. Real greenhouses are, on average, much colder, and should never reach 100% relative humidity.

Under these conditions, the dehumidifier in our example will extract much less than 50 liters per hour.

On the other hand, if the design conditions are more realistic, such as DryGair’s design conditions of 18°C and 80% RH, efficiency can only go up. If it’s ever warmer, or more humid, the dehumidifier will simply extract more water.

Another very important factor to consider is dew point condensation, one of the leading causes of mold development. Cool air can hold less moisture than warm air, so condensation usually occurs when temperatures drop. For this reason, it’s important to choose a greenhouse dehumidifier that can handle low temperatures.

 

Capacity Is Crucial When Comparing Greenhouse Dehumidifiers

Airflow, or capacity, determines how much air a dehumidifier can treat. This has a huge impact when comparing dehumidifiers.

Airflow is measured in terms of volume – square feet, or cubic meters (m3). However, what’s important is the volume of air it can treat in a given time period. Most dehumidifier manufactures present capacity as either m3/hour or CFM (cubic feet per minute).

Dehumidifiers with insufficient capacity won’t just take longer to treat the greenhouse. They may not keep up at all, impacting plant growth and health.

Using multiple dehumidifiers to reach the same capacity is somewhat possible. But it’s important to consider that each unit requires its own space, maintenance, and energy. So, one high-capacity dehumidifier is better than several lower-capacity units.

 

Air Circulation Improves Greenhouse Dehumidifier Efficiency

Most dehumidifiers expel dry air in one direction. So, air in different areas of the greenhouse will experience different humidity levels. This means that even if a dehumidifier has sufficient capacity, it may still fail to keep humidity down all around the greenhouse.

DryGair’s dehumidifiers come equipped with a unique air circulation mechanism. So instead of sending dry air in one direction, they do so in all directions, keeping the entire greenhouse dry.

The humid microclimates that form when conditions aren’t uniform, are where molds like botrytis first develop. They then spread throughout the greenhouse, despite having low humidity levels. So, it’s extremely important to maintain uniform conditions and avoid microclimates.

 

A Greenhouse Dehumidifier Should Match Your Needs

Every greenhouse is unique, and so are their dehumidification requirements. Some of the parameters that affect your dehumidification needs are:

Determining a greenhouse’s dehumidification needs is complex. So, it’s extremely important to choose the right dehumidifier.

DryGair only develops dehumidifiers for horticulture, based on research from Volcani Center. We also employ a team of agronomists solely for the purpose of matching the right solution to each greenhouse, and guiding growers on how to optimize their energy usage.

DryGair extracts 45 liters/hour (12 gallons) at common greenhouse conditions of 80% RH and 18°C (64°F).

Running on only 10 kW, DryGair is highly efficient – extracting 4.5 liters (1.2 gallons) of water vapor per kWh.