Laundry room - Need efficent washers and dryer recs

One of my buildings, a 30 unit, has a three washers and three dryers. I am trying to get the the expenses down, and the water/electric use for the building is pretty high. The dryers are electric, so I was going to update them to gas, however, I wanted to get some recommendations on a new set to buy. Also, I need them to be coin-operated as well.

In addition, does anyone know how to make parking lot light use more efficient? I find the four pole lights using quite a lot of electricity too.