  We propose a method to continually monitor the energy of a quantum system. We
show that by having some previous knowledge of the system's dynamics, but not
all of it, one can use the measured energy to determine many other quantities,
such as the work performed on the system, the heat exchanged between the system
and a thermal reservoir, the time dependence of the Hamiltonian of the system
as well as the total entropy produced by its dynamics. We have also analyzed
how this method is dependent on the quality factor of the measurements
employed.
