Manufacturer Reports

Liquid Desiccant Cooling and Dehumidification Cuts Energy Costs

September 21, 2009
/ Print / Reprints /
/ Text Size+
The DuTreat units cool and remove humidity from the air, providing comfortable conditions in the warehouse while allowing the air conditioning thermostat to be set to 82° so that it rarely operates. (Click on the image for an enlarged view.)

MIAMI - Duty Free Americas Inc. (DFA) reduced warehouse electricity costs 25 percent and eliminated moisture-related damages to goods by installing DuCool’s desiccant cooling and dehumidification systems. The installation of two DuTreat Model DT800/4 desiccant cooling systems alongside two existing conventional air conditioning units made it possible to maintain constant conditions of 76°F and 52 percent relative humidity even in the hot Miami summer when the outdoor temperature and humidity are extremely high and loading dock doors are frequently opened. According to DuCool, energy costs have been reduced because the DuTreat systems are more efficient in handling the heat load and the air conditioning rarely operates.

“Since the DuCool units were installed, the indoor air is cool and dry, we haven’t seen any humidity related product spoilage, and we feel much more comfortable,” said Duty Free Americas operations manager Lorenzo Lorenzo.

DFA operates stores in major international airports that sell items without duties or taxes to passengers who are leaving the country for a minimum period of time. The company’s warehouse in Miami stores goods sensitive to temperature and humidity levels such as tobacco, watches, candy, chocolate, and cosmetics. The large doors in the loading dock area are frequently opened to load and unload products. In the past, the two existing air conditioning systems were set to 60° and operated nearly continuously, consuming large amounts of electricity. The air conditioning units reduced temperature and humidity but could not effectively handle the significant latent load. The high humidity levels and the water dripping off the air conditioners caused damage to expensive products, causing management to take action and find an alternative solution.

DFA evaluated several alternatives and selected the DuTreat system, which uses an innovative liquid desiccant process to cool and remove humidity from the air using minimal energy. In the DuTreat unit, the liquid desiccant is cross flowed with the air from the building, absorbing the humidity from the air while cooling it. The moisture collected from the air is then ejected to the outdoors in vapor form. An embedded heat pump is used to cool the air and the liquid desiccant. The heat extracted in the cooling process is then used for ejecting the moisture collected from the air. Using both the evaporator and condenser sides of the heat pump significantly improves the overall energy efficiency of the system.

Two DuTreat units each process 800 cfm of air. Moving the air from the DuTreat units through the existing air conditioning systems made it possible to utilize the existing ductwork, reducing the cost of the installation. The DuTreat units cool and remove the humidity from the air, providing comfortable conditions while allowing the air conditioning thermostat to be set to 82° so that it rarely operates. The DuTreat units take in return air at a temperature of 76° and 52 percent relative humidity and provide treated air at 71° and 29 percent relative humidity.

The workers in the warehouse are very happy about the improved indoor air quality and say that the air inside the warehouse feels like “mountain air.” The DuTreat units keep ducts dry to eliminate fungus and bacteria growth. The lower humidity level in the warehouse reduces moisture-related damages and prevents growth of mold and mildew.

For more information, visit

Publication date: 09/21/2009

Did you enjoy this article? Click here to subscribe to The NEWS Magazine

You must login or register in order to post a comment.



Image Galleries

2014 Energy Efficiency Forum

Highlights from the 25th annual Energy Efficiency Forum in Washington, D.C.


NEWSMakers: Jeremy Begley

Jeremy Begley, home-performance specialist and Web and social media manager with National Heating and Air Conditioning Co. in Cincinnati discusses how and why you should add home-performance philosophies to your contracting repertoire. Posted on Sept. 12.

More Podcasts


NEWS 09-15-14 cover

2014 September 15

Check out the weekly edition of The NEWS today!

Table Of Contents Subscribe

Venting R-22

The NEWS reported that a man received prison time for venting R-22. Should EPA step up enforcement?
View Results Poll Archive


2014 National Plumbing & HVAC Estimator

Every plumbing and HVAC estimator can use the cost estimates in this practical manual!

More Products

Clear Seas Research


Clear Seas ResearchWith access to over one million professionals and more than 60 industry-specific publications, Clear Seas Research offers relevant insights from those who know your industry best. Let us customize a market research solution that exceeds your marketing goals.


Magazine image
Register today for complete access to Get full access to the latest features, Extra Edition, and more.


facebook icontwitter iconyoutube iconLinkedIn i con