A specially designed air-cooling (and heating) system using Earth Tube Heat Exchanger (ETHE) was installed in the dwelling of a 15-year old white tiger (Panthera tigris) named Mahesh at Kamala Nehru Zoological Garden, Ahmedabad (India) in October 2000. This was done to alleviate the stresses experienced by Mahesh in summer, which is long and hot; and in winter nights, which can be quite cold. Summer temperatures in Ahmedabad remain around 40oC for a long time and can reach as high as 45oC. Night temperatures in winter can drop to 10oC or below. The system does both--provide cooling in summer and warming in winter. In winter the system warms up the ambient (cold) air by as much as 10oC at night. In summer the system cools the ambient (hot) air also by as much as 8 - 10oC during the day.