Yea you are getting it -

Honestly, think of it this way: your auto engine works on the same principles (minus the distributed networking). It burns fuel in order to provide propulsion, but the heat and the kinetic energy of the motor is captured to heat the occupants in the summer, cool them in the winter, and run all of the electronics housed in the vehicle. That's why we call the concept Exergy.

"In thermodynamics, the exergy of a system is the maximum useful work possible during a process that brings the system into equilibrium with a heat reservoir. When the surroundings are the reservoir, exergy is the potential of a system to cause a change as it achieves equilibrium with its environment. Exergy is the energy that is available to be used."