  The mathematically sound theory of quantum open systems, formulated in the
70-ties of XX century and highlighted by the discovery of
Gorini-Kossakowski-Lindblad-Sudarshan (GKLS) equation, found a wide range of
applications in various branches of physics and chemistry, notably in the field
of quantum information and quantum thermodynamics. However, it took 40 years
before this formalism has been applied to explain correctly the operation
principles of long existing energy transducers like photovoltaic,
thermoelectric and fuel cells. This long path is briefly reviewed from the
personal author's perspective. Finally, the new, fully quantum model of
chemical engine based on GKLS equation and applicable to fuel cells or
replicators is outlined. The model illustrates the difficulty with an entirely
quantum operational definition of work, comparable to the Problem of Quantum
Measurement.
