It depends on the definition of OU.
The most useful I have come across is Patrick's: the ratio of the energy out divided by the energy YOU put in. (People are expected not to be so childish as to apply this to heat pumps and pv panels).
According to this definition a heat pump produces OU, but this is not what we want because a heat pump requires electrical energy which is not free. I suggest to keep this definition but on condition that we talk about "useful energy", that is to say energy that can be converted from one form to another without theoretical loss (potential, magnetic, electric, kinetic...). This includes all forms of energy EXCEPT thermal energy. If we have OU with these energies, then we can loop the system, while this is not possible with a heat pump. Thermal energy is a degraded form of energy, it is the one that represents the main losses of all the other forms of energy when we transform them. OU concerning thermal energy does not allow "free energy" unless the COP was really big (e.g. COP=10? to be specified), so we really have to differentiate thermal energy from others.
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"Open your mind, but not like a trash bin"
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