Why does an electric motor at steady state have zero du/dt and dS/dt?

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wynnl
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For the following question, the solution manual sets du/dt (change of internal energy) = 0. Moreover, it also set the change of total entropy to zero. Why is that?

An electric motor under steady load draws 9.7 amperes at 110 volts; it delivers 0.93 kW of mechanical energy. The temperature of the surroundings is 300 K. What is the total rate of entropy generation Sg ? What is its origin ?
 
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wynnl said:
For the following question, the solution manual sets du/dt (change of internal energy) = 0. Moreover, it also set the change of total entropy to zero. Why is that?

An electric motor under steady load draws 9.7 amperes at 110 volts; it delivers 0.93 kW of mechanical energy. The temperature of the surroundings is 300 K. What is the total rate of entropy generation Sg ? What is its origin ?
Energy is conserved. I would expect some entropy generation (the problem statement even asks for its amount!), however.