As more and more parts of the country become increasingly concerned about limited water resources, NIMBUS is ready with blue solutions. This eco-conscious technology reduces water consumption to help lessen demands on the water supply.
The NIMBUS Virga adiabatic cooling system maintains optimal operating temperatures for commercial HVAC equipment and industrial processes. Like cooling towers, these systems are designed to prevent overheating and damage to equipment. However, Virga adiabatic cooling technology uses much less water than traditional towers. Jerry Petit, Director of Business Development at NIMBUS, explains, “Virga introduces a conservative amount of fresh water into the cooling process only when necessary on those hot design days. This process eliminates the need for chemically treated water, costly maintenance programs, and the health risks associated with standing water.”
When a traditional cooling tower is working, it’s using water. In most parts of the United States, cooling towers run eight months out of the year. In warm climates, they run all year round. These cooling towers constantly use and lose water through evaporation and blowdowns. “In addition to the water needed to cool, outdoor air is also being pulled in to help separate the warm water from the cool water,” says Petit. “And with that outdoor air comes dirt, bugs, leaves, and more. All that extra debris eventually settles on the bottom of a cooling tower in the sump. When this happens, the tower uses blowdowns to clean it out.”
Blowdowns intentionally purge a portion of the circulating water from the system to reduce the concentration of dissolved solids and impurities in the water. Depending on the environment and the specifics of the cooling tower, blowdowns can happen a few times a week or once or twice a day. In every situation, large volumes of water are used to clean out the sump, and the dirty wastewater is returned to the municipal water system.
“Blowdowns represent a huge annual loss of water,” says Petit. “The bottom line is that when a tower is on, it’s losing water. Maybe it’s losing water from evaporation, blowdown, or drift, which means it’s also draining dirty water, and that water needs to be treated by municipal water authorities. That usually translates into expensive drain fees, which can be one and a half to two times the cost of water itself, so reducing those fees is an important step towards decreasing operational expenses.”
Virga Is the Blue Alternative
Virga Adiabatic Cooling is a water-saving, or “blue,” alternative to traditional cooling towers. Cooling towers and Virga adiabatic cooling systems both keep water temperatures at about 85 degrees Fahrenheit. But Virga primarily uses outside air to cool, while traditional cooling towers require substantial amounts of water.
In a traditional cooling tower, cool water goes to the bottom of the cooling tower into a sump. That water is then used to cool another piece of equipment. But adiabatic cooling technology works a little bit differently. In the Virga adiabatic cooling system, the process fluid used to cool is in a closed loop. It has fans that pull ambient outdoor air across a coil filled with the process fluid. This maintains the 85-degree fluid temperature. “That means that, for most of the year across the country, Virga’s adiabatic cooling technology uses nothing more than the outdoor ambient temperature to maintain its cool,” says Petit. “On the hottest days, or in the hottest climates, the Virga adiabatic cooling systems use a misting water spray to drive the ambient air temperature down as it’s pulled across the coils. The misting provides a heat rejection boost using a minimal amount of water. In almost every environment, using the Virga system saves substantial amounts of water, sometimes as much as 90 percent.”
In addition to using less water, adiabatic technology also protects against the spread of Legionella bacteria, which can cause Legionnaire’s disease. This potentially deadly respiratory condition can occur when the bacteria grow in stagnant water. While virtually all water has very low concentrations of Legionella bacteria, those levels can skyrocket when the bacteria multiply in sitting water.
This kind of sitting water can be an issue for cooling towers with open sumps. In traditional cooling towers, the sump water is often treated with chemicals. However, adiabatic cooling technology doesn’t allow any standing water, so it doesn’t require chemical sanitation, and it virtually eliminates the possibility of spreading Legionnaire’s disease. “Our process fluid is in a closed loop, so that’s never going to drain out,” says Petit. “When needed, the misting spray comes from a city water line. When the Virga stops spraying, the copper tubing automatically drains the water in the tubes, so there is no standing water in the lines.”
Virga is a Smart Choice for a Major Metro Hospital System
Eco-friendly operations combined with higher health standards make Virga an easy choice for healthcare engineers and contractors. A prominent New York City area hospital system recently committed to installing seven of the Virga adiabatic coolers to replace traditional dry coolers that were used for data storage.
This client noticed that when it got really hot in the summer, it was getting harder and harder to maintain the desired cool temperatures. In a data center environment, cooling is critical. When this hospital looked for better solutions for its essential cooling needs, it turned to NIMBUS for the appropriate technology. Virga adiabatic cooling systems can provide colder process fluid on even the hottest days of the year because of the misting feature that provides an extra heat rejection boost.