1999 ASHRAE Technology Awards: Ventilation in the Commercial Environment PDF

Refers to the JCPenney department store in Baton Rouge, Louisiana, a 125 000 ft² (11 613m²) building, in an area with high humidity and warm temperatures. The adoption of Standard 62-1989, leading to greater volumes of outdoor air, caused an increase in the HVAC equipment capacity needed for maintaining comfort conditions. Goes on to describe how the store has saved approximately 50 tons (176 kW) of cooling capacity using an evaporative cooling DX rooftop unit with an enthalpy heat wheel. The wheel, which consists of a heat-absorbing, moisture-absorbing matrix surrounded by an aluminium and steel casing with a motor to drive the rotation) removes moisture and heat from the outdoor air in summer operation and, through rotation, transfers it to the cooler, drier exhaust air from the store. In terms of electrical energy usage, the evaporative condensing system with a heat wheel saves approximately 7% in annual energy consumption and 17% in annual peak demand in comparison to the VAV rooftop system.