“Over the years we have struggled with conventional air conditioning,” Vary explains. “With our old system, you could feel the humidity in the store. Even though we were making the air cold, it wasn’t enough to make people comfortable. We had shutdowns where refrigeration would fail. Our utility bills showed the impact of hot and humid summers. At one point, we considered installing a desiccant wheel but it was too expensive and used too much energy, as well as would be costly to maintain. We also didn’t have the space for the large operating footprint.”
Vary sought a solution that would meet her store’s air-conditioning needs while providing a short payback for her upfront equipment investment. She also was committed to sustainability and energy reduction. Vary hired Intelligent Power and Air Solutions (IPAS) Inc., a firm with expertise in humidity and cooling with a goal of energy efficiency and productivity, to assess her store’s conditions and recommend options. IPAS positioned sensors to benchmark energy usage by mechanical and HVAC equipment, as well as monitor the store to determine specific areas of energy consumption. The store was monitored for almost six months.
The Solution
IPAS recommended liquid desiccant technology to resolve Bel Garden Bi Rite Supermarket’s humidity issues. Liquid desiccant technology features a non-toxic salt-brine solution that removes moisture from the air naturally while cooling a space. When heated, the liquid desiccant releases the moisture outside in the form of warm, vapor air, which eliminates condensation. The liquid desiccant is also a natural disinfectant, eliminating bacteria, microorganisms and odor from the air. (Click on the diagram for further explanation of how the system works.)
The system is comparable in size to traditional direct-expansion air conditioning and considerably smaller than dry desiccant systems. Additionally, the upfront costs are relatively the same as equivalent vapor compression systems and considerably less expensive than dry desiccant units while incurring minimal maintenance expenses.
The system uses 30 to 80 percent less energy than conventional air-conditioning systems. The moisture removal properties of the liquid desiccant allow the system to more efficiently regulate space conditions to the desired set point, eliminating the need for over-cooling or heating the air to remove humidity. Also, the system can be designed to take advantage of waste heat, geothermal and other renewable-energy sources to further enhance these systems’ operating efficiencies.
IPAS recommended a system that eliminates the potential for carryover; therefore, there is no corrosive element from the salt-brine solution introduced into the environment. Instead of atomizing the salt solution as legacy units have done in the past, the system IPAS suggested cascades the salt solution over a honeycomb filtration medium. The solution then creates a bond with the filtration medium, which is stronger than the velocity of air being introduced through the system. Further, steps have been taken to add additional filtration to ensure no salt solution exits the system.