Not trivial if they a bunch of chargers. I work for the state in California and we have chargers at work but are charged for them around $.29/kWh which is cheaper than Tesla I think.
Are they fast DC chargers or level 2 chargers? If it's the former, then that is cheap. If it's latter, then that is some expensive electricity.
I'm in Washington where electricity is cheaper, so 29 cents per kWh is not much cheaper than Tesla's superchargers. The closest one to me is 31 cents in the middle of the day and goes as low as 20 cents per kWh at night. I pay 8 cents per kWh at home, which is where I charge (at much slower speeds) unless I'm on a road trip.