I am ordering these. the 4 bulb fixtures are the 8 footers. Do you have 2 or 4 fixtures per bay?
Not addressed to me but i think people need to keep in mind needs are different for an IBA, SS Bay, or tunnel.
Since the customer stays in the car in the IBA or tunnel, I think one 320 scots dale light on the ceiling every 15 feet or so, or a four footer on each sidewall in the center of a 25' bay may do it. Thisputs the light where needed in the area of the driver / center of the bay.
For a SS I don't think 2 lights, one on each sidewall will cut it. It won't illuminate the sides down low enough all the way to the fron & rear as well as the front and rear of the car for the customer to see what they are doing.
Some guys use 2 ceiling lights like 320 watt Scottsdales Kitty corner but have White covered FRP or some material giving great reflection. Others here started with one 8 foot tube on each sidewall and then had to add more.
I inherited a place with 4, four foot HO fixtures, two on each sidewall about 8 foot high, seperated by about 8 feet. Assume for the moment a 4 foot light will throw light 4 foot to either end, this gives a spread of 24 feet alongeach wall suffcient to fully illuminate the sides and ends of the car.
The double four foot HO fixtures give plenty of light and at 60w per bulb it's 120 per fixture and 480 per Bay.
So, your cost to operate is a little more than 2, four tube T5s which would be 216 watts each or 432 per bay, but the dispersion is better. less to operate than two 320 W Scottsdales at 640 Watts. More than some suggest with regard to 2 eight foot fixtures, but for an SS bay I don't see how you would get the dispersion. Both along the ceiling in line for an IBA or tunnel I could see.