How does the law of conversation of energy apply to machines

Yes

Explanation:

Let's use a fan as an example. So a fan will spin around as long as it is connected to power from a power outlet. Now, if your remove the fan from it's source of power, it will no longer have the force to resist other forces, such as gravity or friction. These other forces will cause the fan to come to stand still, as it cannot produce more energy than it started with, and it loses its energy to thermal energy from friction.