The cooling is typically obtained through a refrigeration cycle, but often evaporation or free of charge cooling is applied. Air conditioning programs can also be manufactured depending on desiccants (chemical substances which take away moisture through the air). Some AC programs reject or retail store heat in subterranean pipes.[2] 1288439 https://docs.google.com/spreadsheets/d/1sFkX-195bzbspltn6kI7pJAwHC_IWJIWy0giWMghe84