Case study on Ultraviolet C technology in the performance of an air conditioning system.
by UV Resources*
When competing to be one of the main office tenants in a high-rent market like South Florida, your building must have the best finishes and systems to stand out from the competition. That's the ongoing challenge that motivates Bunnie Willis, Vice President, Senior Property Manager at the 12-story BayView Corporate Tower in Fort Lauderdale. Built in 1973, the 412,000-square-foot Class A building owns 13 corporate tenants, including AT&T, Whole Foods and Landmark Worldwide.
Willis routinely looks for ways to improve the value of BayView and the other Florida commercial properties she manages for the New Boston Fund, Inc., a private real estate investment management firm worth billions of dollars. In July 2011, during a routine evaluation of the BayView Tower's mechanical systems, Willis learned that she could provide her tenants with cleaner, healthier air through moderate improvements to the building's HVAC systems. One such improvement also promised energy savings, a reduction in maintenance costs and the extension of the life of the equipment.
The use of ultraviolet (UV) lighting
A key component in the HVAC system improvements was the addition of ultraviolet C (UV-C) light lamps. Widely in use since the nineties to improve indoor air quality (IAQ) and later to improve heat exchange efficiency, increase airflow and reduce maintenance, UV-C wavelength eliminates, and further prevents, the accumulation of microbes and organic materials in cooling coils, air filters, duct surfaces and drainage trays of air conditioning systems.
However, it is the technology's ability to potentially reduce the energy consumption of HVAC systems by 10 to 25 percent that drives nine out of 10 UV-C installations, says Bruce Fontaine, Vice President of Business Development and Operations at Sustainable Management Solutions, a national energy efficiency consultancy specializing in commercial HVAC systems. reductions in the use of electricity and water, with offices in Pompano Beach, Florida. Fontaine's team recommended the sustainable UV-C solution, product selection and installation at BayView.
In the end, an independent audit documented an increase of up to 47% in the building's airflow levels following the installation of UV-C energy, which also resulted in a sufficient reduction in energy use to pay for the upgrade in just three months – a 90-day return on investment. The audit not only demonstrated an improvement in airflow, but also a reduction in the energy consumption of the ventilation and cooling system.
According to the U.S. Department of Energy (DOE), Willis isn't the only one focusing on using the HVAC system as a potential source of savings, given that this equipment equates to 30 to 50% of the building's total energy use: a figure that can be even more pronounced in southern climates like Florida.
In meeting the recommendation to add UV-C technology to BayView's air handling units (AHUs), Willis, a certified Real Estate Administrator and chair of the Fort Lauderdale/Palm Section of The Building Owners and Managers Administration, did her job of learning more about this technology.
Willis met with Chief Engineer Miki Minic, who had successfully used UV-C lamp systems in other buildings managed by New Boston Fund and Stiles Property Management.
"The benefits of UV-C energy are many," says Minic, who enthusiastically supported the installation of UV-C energy. "Most important of all is improving indoor air quality levels, so tenants can enjoy cleaner, healthier air. Absenteeism due to the spread of unsafe microorganisms through HVAC systems is almost eliminated. What's more, the life of the equipment is improved, the costs of downtime and preventive maintenance for cleaning the coils, drainage trays and the purchase of coils and drainage treatments, etc., are significantly reduced."
Willis of BayView also visited similar properties in the area with UV HVAC lighting installations and sought the opinion and experience of his peers about this technology.
"After my research and meeting with other commercial property managers who had installed the UV lighting, I bought the benefits of the technology," he added.
Installation in BayView
With two cooling towers, three chillers and 24 air handling units (two per floor), the UV installation at BayView Corporate Tower presented some challenges, says Darren Ambrosi, project manager at Sustainable Manager Solutions.
"The existing air treatment units were 25 years old and offered limited access to evaporators," says Ambrosi, regarding the refurbishment project that began in January 2012. "Due to limited access, we recommend UV Resources' deviceless, high-performance RLM Xtreme UV-C lamp system. This modern UV-C system installs in about half the installation time of conventional devices and offers flexible configurations like those required by BayView."
Minic, the building's chief engineer, had experience of the Xtreme RLM system and supported the product selection. As a result of the flexibility of installing the DEVICE-FREE UV-C lamp system, improvements were completed in just four days using only two installers.
After the installation of UV-C, efficiency consultant Fontaine was impressed with the increase in system performance.
"The overall transformation in terms of efficiency was incredible," says Fontaine, who estimates that the project's energy savings yielded a three-month return on investment. "Airflow levels increased by 47 percent in an air handling system, or about 10,000 CFM, the coils look like new and the condensation trays clean the air fantastically."
Return on investment
As with any major capital project, return on investment is a critical component that must be independently demonstrated. Willis commissioned an independent performance test to evaluate the success of the installation by HVAC consultant John Kneiss, president of K&P Mechanical Solutions, Inc., with offices in Dania, Florida.
"Our goal was to measure the performance of the cooling coils of the HVAC system before and after the installation of the UV fittings," explains Kneiss.
During the speed profile tests carried out before the RLM Xtreme installations, Kneiss discovered different speed levels, which indicated that some parts of the coils were much dirtier than others.
"It was easy to notice that some sections had high speeds and other sections low, indicating an accumulation of debris in the areas with the lowest speed," he said. "The velocity readings in our base measurements were not stable."
When Kneiss returned after the installation of the UV lighting system, he used the same instruments and test procedures, and found that the airspeed readings were much more stable, this time, on the entire surface of the coils.
"Our opinion after reviewing the results and differences was that the performance of the cooling coils improved significantly from the first readings," Kneiss recalls. "Coil velocities were more stable on all coils and there was also an improvement in dew points with the coils turned off. For us in South Florida, this is an important benefit."
BayView's Minic highlighted the improved efficiency of the individual HVAC system components and a drop in power consumption following the installation of the UV-C system.
And as far as Willis is concerned, she is so pleased with the results that she is planning the future use of UV-C technology and RLM-Xtreme.
"During the first month, we saw an immediate reduction in our energy costs, which has remained consistent since installation," Willis explains. "I believe so strongly in this improvement that we are preparing to introduce it at one of our other properties in Doral, Florida. We are very satisfied with the decision to install the UV lighting."
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Project Profile
Location: Fort Lauderdale, Florida.
Structure: Class A, 12-story office building covering an area of 412,000 square feet built in 1973
Air conditioning equipment: Two cooling towers, three coolers (250, 430 and 750 tons) and 24 air handling units (2 per floor)
System Presented: UV-C lamp system without RLM devices from UV Resources, Santa Clarita, Calif.
Benefits of UV energy: The germicidal wavelength of UV (UV-C) energy can reliably deliver cleaner, healthier air by preventing microbial buildup in the coils, drain trays, air filters, and duct surfaces of HVAC systems. UV-C energy also eliminates pathogens in airflows. Proper application of UV-C energy results in improved heat transfer to coils, reduced energy use, fewer odors, reduced cleaning downtime, and reduced damage. These effects can also reduce the incidence of airborne allergies, colds and flu, which can result in lower rates of absenteeism.
Engineer: Stiles Corporation, Fort Lauderdale, Fla.
Installation time: Four days, with two installers.
Project Manager: Sustainable Management Solutions, Pompano Beach, Fla.
End date: March 2012
* UV Resources (UVR) is a company specializing in education, design and innovative engineering of affordable ultraviolet-C equipment for various HVAC applications You can contact Dan Jones at email: [email protected]