Meeting/Event Information

Oversized Air-Conditioning Systems and Overcooled Buildings in Hot and Humid Climates

GBCI Approved | 1 CE Hour | 0920020207

AIA Approved | 1 LU | OASOB19

Why are air-conditioned buildings in hot and humid climates so cold that one gets reminded of carrying a jacket when going to office?  Would raising the set point temperatures in these buildings do the trick?  What are the engineering challenges that necessitate a relook at the way air-conditioned buildings in such climates are designed?  This talk will review some of the fundamental issues of cooling and dehumidification facing the HVAC designer and the inevitable and inherent design of an oversized system and its undesirable consequences in terms of an overcooled indoor environment.  It will provide an understanding of the psychrometric challenges involved in cooling and dehumidification at peak and part loads in hot and humid climates. Possible solutions to creating a more thermally comfortable and healthy indoor environment that can also save energy will be discussed.

  Chandra Sekhar, Ph.D., Fellow ASHRAE, ISIAQ and Engineers Australia (FIEAust), is currently a Professor and Programme Director (MSc-Building Performance and Sustainability) in the Department of the Built Environment at the National University of Singapore. His research interests include thermal comfort, ventilation and IAQ, airborne infection control, energy efficient HVAC systems and building energy analysis. He has more than 300 publications in these fields in international journals and conferences. He has delivered several Keynote talks in international conferences around the world. He has been an ASHRAE Distinguished Lecturer since 2006 and is regularly invited as a speaker around the world. He has been recognised through several awards from ASHRAE, SHASE Japan, ASEAN, Singapore and India. He is currently ASHRAE Vice President and Board Member (2023-2025), a member of SSPC241 (Control of Infectious Aerosols) and TC2.1; and a consultant of Planning Committee and SSPC62.1. Within ASHRAE, he is past Chair of Environmental Health Committee, past Vice Chair of Residential Buildings Committee and member of many Position Document Committees. He has also served the ASHRAE Singapore Chapter in various capacities, including as its President during 2010-2011 and as a BOG member. He was involved in the Residential and Applications teams of the ASHRAE Epidemic Task Force. He was an Invited Member of the WHO Environment and Engineering Control Expert Advisory Panel (ECAP) for COVID-19. He is also actively involved in standardization activities in Singapore.