Now, I thought about this last year some time and decided against it. I know for one that if I was renting an apartment for a holiday and then found I had to pay for electricity, it would be a non starter and discarded. Of course, it the ad "forgets" to mention the fact electricity isn't included, that could open another can or worms! Remember the "good" old days at Butlins/ Pontins, et al when you had to take your stash of 50p's with you? That was left behind a long time ago.
Is the idea that rental rates will be cheaper as electric isn't supplied? Could still cqtch unwary punters out! It may be a consideration if you were only to add it to the air conditioning for example, but then you would need the provide fans as an alternative. At the end of the day, you have to set your rates to cover your costs and hope that guests don't abuse the situation too much. There are gadgets available that will switch off the air con for you if the room is empty for periods of time, I have one in my apartment.
On the other hand, if it is for long term renters it isn't such a bad idea. Too many stories on various forums of tenants not paying utilities, so better safe than sorry.
Just my opinion.
Mark