Economic benefits of improved condenser features for air-cooled chillers serving an air-conditioned hotel

Abstract

Air-cooled chillers can take up around one-fourth of the total electricity consumption of an air-conditioned building. This paper evaluates the potential electricity cost savings of these chillers with improved condenser features of condensing temperature control (CTC), evaporative pre-coolers (EC) and variable speed condenser fans (VSF). A validated model for an air-cooled screw chiller was used to ascertain how the individual and mixed features influence the annual electricity consumption of chillers operating for the cooling load profile of a hotel. With regard to a chiller plant with a 15-year lifespan, the life cycle electricity cost savings are estimated at between HK$ 2,291,247 and 8,320,732, depending on the features used. The simple payback of the features could range from 1.07 to 3.32 years. These findings show how chiller manufacturers and building owners can profit from implementing energy efficient technologies for air-cooled chillers.