Because energy is needed to separate the molecules in a liquid, the working fluid absorbs heat from the environment when its liquid form evaporates into a gas.
(energy; is needed; ) (its liquid form; evaporates; L:into a gas) (the working fluid; absorbs; heat; from the environment; T:when its liquid form evaporates into a gas)
energy its liquid form the working fluid
is needed evaporates absorbs
L:into a gas
heat from the environment T:when its liquid form evaporates into a gas