In Focus: Adiabatic Cooling

Water and energy use are increasingly a concern for organisations for both financial and environmental reasons. Adiabatic cooling, twinned with intelligent controls, can play a significant role in reducing the consumption of both. Adiabatic technology also extends the range of cooling and refrigeration systems that use natural refrigerants and can help to future-proof cooling systems as global temperatures rise.

“There are significant benefits from using an adiabatic cooling system compared to a conventional cooling tower, particularly in the increasing number of regions where water scarcity is becoming an issue,” says Raúl Alanís, Projects Coordinator at Güntner. “Güntner has long been a leader in this field, and our technology provides excellent air-cooled heat exchanger or condenser and dry cooler performance with a small footprint and low operating costs.”


There are pressing reasons to try to cut down on both water and energy consumption.

Increasing demand, pollution, and, in particular, climate change contribute to a water shortage in many regions of the world. As a result, there is increasing regulatory and ethical pressure on companies to do all they can to cut water consumption. There is a financial imperative, too—the law of supply and demand applies to Earth’s most precious resource, and water prices are rising for many.

When it comes to energy, there are also powerful reasons for cutting consumption. Although countries around the world are attempting to switch to renewable sources of energy production on the road to Net Zero, only a handful currently rely solely on renewables. Fossil fuels, including coal, oil, and natural gas, still supply around 80% of the world’s energy, accounting for more than 75% of greenhouse gas emissions. Recent geopolitical events have also caused energy prices to spike, affecting a number of countries. Even places such as Brazil that rely heavily on hydropower have seen prices increase due to water shortages. In the years ahead, it’s likely that pressure on both water and energy resources will remain high.


Güntner’s Adiabatic Cooling System brings significant water savings and energy efficiency in comparison with a conventional cooling tower, plus other benefits.

Conventional cooling towers and evaporative systems use large amounts of water. An adiabatic cooling system, however, operates as a dry cooling system for most of the time, only using water when the ambient temperature is particularly high or demands on the cooling system as a whole are particularly heavy.

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Güntner has been a leader in adiabatic technology for more than thirty years. Its Adiabatic Cooling System with hydroBLU™ technology features cutting-edge heat transfer and controls technology, reducing water consumption by up to 90% compared to a conventional water-cooled system. Units are available in a wide capacity spectrum, from 40kW to more than 2,500kW. Wet when you need it and dry when you don’t, hydroBLU™ combines the reliability and ease of use of a dry cooler/condenser with the system efficiencies associated with water-cooled heat exchangers.

“The most important thing is that we developed this as a system,” says Herbert Schupfer, Head of Future Solutions at Güntner. “We didn’t just attach pads and start spraying a lot of water, which is what a lot of early solutions did. Our GHM controller has a patented algorithm that makes it possible to optimise the amount of water being used, taking into account environmental data such as air temperature and humidity, as well as how much water is available and how much can be evaporated. Then it’s up to the customer to decide how much water to use, or how much performance to gain or energy to save.”

Güntner experts will configure the cooling system specifically for the user’s preferences in terms of optimising either water or energy savings, taking into account historical weather data at the installation site. Once the system is in operation, the built-in smart control continually monitors all significant parameters and automatically adapts the operating mode to the prevailing requirements. This ensures that operating costs are kept low and individual units are optimised.


Güntner recently redeveloped its hydroBLU™ technology by introducing new, thicker pads, increasing the adiabatic process’s efficiency. The wetting system has also been revised, with all components easier to reach, making installation and maintenance simpler.

At a site in Montague, CA, Güntner was able to evaluate annual energy and water consumption with hydroBLU™ compared with a conventional evaporative cooling unit. The hydroBLU™ brought 45% annual savings in combined energy and water costs and showed an 80% reduction in water consumption: the evaporative cooler consumed a staggering 1.3 million gallons of water annually compared with 260,000 gallons by the dry cooler with hydroBLU™.

In addition to reducing water and energy consumption, there are other benefits from using Güntner´s adiabatic technology. There are few maintenance requirements, as no water treatment or chemicals are required. And in safety terms, the possibility of bacterial infestation is minimised, as there is no aerosol formation and no stagnant water accumulation. The heat exchanger coil remains completely dry, avoiding deposits on the fins.


Existing systems can be easily adapted, bringing a range of benefits

In Europe, Güntner offers a retrofitting service, adding hydroBLU™ to existing refrigeration and cooling systems. “It’s quite straightforward, it only takes a few days, and the existing system continues to run during the installation,” says Marco Baumann, Director of Service Europe in Güntner. “We can calculate in advance what the benefit will be and how long it will be before the customer gets a return on investment.”

Retrofitting is not just a way to cut down on water and energy consumption—it can also be used as a risk management strategy. If global temperatures continue to rise as predicted, systems that were first planned five or ten years ago may soon not have the capacity to cope during peak periods. Retrofitting with hydroBLU™ offers a low-cost way to future-proof a system.

One of Europe’s leading supermarket chains has already gone down this road. In 2021, when the cooling system at one of its stores in France was having difficulty during heatwaves, Güntner solved the problem by retrofitting hydroBLU™. Impressed by the result, the company subsequently retrofitted many other locations in France, Hungary, Germany, and Cyprus. And having seen the benefits of an adiabatic system, the chain now installs hydroBLU™ as a matter of course for new projects or refits in warm regions. Retrofitting of hydroBLU™ can also be a convenient and cost-effective solution if national regulations require a reduction in energy use.

“There were recent regulation changes in France that obliged companies to improve the overall energy efficiency of their buildings,” says Schupfer. “A lot of companies had already introduced energy-saving measures for both financial and sustainability reasons, so they were looking for a way to make further reductions. Retrofitting offered a non-invasive and relatively low-cost solution.”


Adiabatic systems can be used across a wide range of industries, particularly in air-conditioning, process cooling, refrigeration, and data centre applications.

When a discount store company decided to renovate the comfort cooling at its 24 distribution centres across the US, reducing water usage was a major consideration. For that reason, they chose to use Güntner High Density Ammonia Condensers with hydroBLU™. “They realised they could reduce their water usage by between 60% and 90% compared with conventional cooling towers,” says Neil Boucher, National Sales Manager for Güntner in the USA. “We’re talking about millions and millions of gallons of water saved.”

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One of the leading manufacturers of household appliances in Mexico needed to reduce water consumption in its plants nationwide and settled on Güntner’s V-shape VARIO Dry Coolers with hydroBLU™ as the best option for the cooling system of its air compressor rooms, due to its ease of installation, capacity, and a great variety of configurations.

In Zhangjiakou in northern China, a data centre run by one of the country’s biggest ecommerce companies uses a new technology that’s recently been gaining ground in the sector: immersion cooling. This means the servers are hermetically sealed inside a special, non-conductive liquid, which evaporates and then condenses at a cooling spiral at the top of the chamber. The heat is dissipated by four Güntner’s V-shape VARIO Dry Coolers with hydroBLU™ on the exterior of the building. The centre saves around 95% of cooling energy and 80% of cooling costs compared to those using conventional cooling systems.

Cryptocurrency mining uses huge amounts of energy, so companies tend to migrate to where costs are lowest. For one company, that meant a remote area of Texas—but unfortunately, water was not in plentiful supply. It chose an adiabatic solution of 40 Güntner’s V-shape VARIO Dry Coolers with hydroBLU™ that would allow it to operate at peak efficiency while using minimum water.


Güntner has long championed the use of natural refrigerants, in particular carbon dioxide, ammonia, and hydrocarbons. Adiabatic cooling has benefits for all systems using natural refrigerants, but in particular, it allows CO2 systems to operate more efficiently in transcritical mode in warm and hot climates.

German wholesale chain Metro Cash & Carry plans to use natural refrigerants in its stores worldwide by 2030, wherever it is economically feasible. This includes China’s first transcritical CO2 plant at the company’s Beijing outlet. Peak summertime temperatures in the city can reach 104°F, but thanks to a Güntner V-shape VARIO Gas Cooler with hydroBLU™, the temperature of the air that reaches the coil is significantly lower, improving COP by up to 50%.

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The stated aim of the Olympic and Paralympic Winter Games that took place in China in 2022 was to make the huge event as environmentally sustainable as possible. For that reason, the 129,167ft2 ice surface at Beijing’s new National Speed Skating Oval, known as “The Ice Ribbon,” is maintained at a constant temperature by means of a transcritical CO2 cooling system. The biggest CO2 project in China, it includes six V-shape VARIO Gas Cooler with hydroBLU™.

The largest transcritical CO2 refrigeration installation in Mexico operates with the help of two Güntner V-shape VARIO Gas Cooler with hydroBLU™. A distribution centre in Mexico City with cold storage and food processing areas needed a system that combined low water consumption with a natural refrigerant with low global warming potential and maximum efficiency.

Water shortages are common in Mexico City, where the huge underground aquifer that serves the local population is being drained more quickly than it can refill. When local infrastructure solutions provider Arcosa planned a new cold storage and flash freezing plant for one of Mexico’s leading fast food franchises, the answer was Güntner V-shape VARIO Gas Cooler with hydroBLU™ in a single cooling system using ammonia as the refrigerant for both the old and new plant, saving on both water and electricity costs.

A meat processing brand in America was concerned with meeting not only customers’ flavor standards but also the highest quality and safety standards in the industry. It chose to operate a low-charge ammonia system combined with a Güntner V-shape VARIO Gas Cooler with hydroBLU™, resulting in low operating costs and easy maintenance.