I will also say to anybody that claims they have "free electricity" to check the realities of of their situation. Somebody is always paying for the electricity they use, but they think it's free" because they have paid for a "normal" amount for their apartment, dorm room, or parent's basement. The key work here is normal, or expected usage amount. Beside the expectation of whoever is paying for the electricity, you will need to look at the capacity of your electrical service. Student dorm room might have a couple of outlets, probably all on the same circuit. When I went to college, there were serious restriction on things like "hot plates", other high power devices. That wasn't just to annoy folks, it was because the place wasn't wired to support more than some lights, a couple of computers, and maybe a TV. I seriously doubt that college dorms are wired that much better today to support a killowatt or two of Bitcoin mining hardware.
Same thing, on a slightly different scale for your apartment or parent's basement.
Think twice about using your employer's space and electricity for mining. While some may be cool with a small amount of mining that doesn't disrupt things, other employer's have zero tolerance Bitcoin mining on their dime as it were.
There is only one situation I would have felt decent with "free electricity". In student housing for university the apartments bragged about electricity included the most they could charge was a extra "peak charge" of 25 dollars no matter how high it truly was. I didn't mine there since I had 3 roomates and they would have gotten the charge to, so would have been a not so nice guy move.
If I would have went for the apartment rented out myself i definitely would have mined in one of the rooms. But most "free" I think parents or small landlord pays. Mine was unique it was multi-million dollar company that put in nice apartments in big university towns.
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