Your a little late to the party. We installed LED lighting about 4 or 5 years ago. Saved us around $45 a month on the light bill, we leave our lights on 24/7. It cost us around $1100 to re-lamp the car wash with LED lights so we've gotten our money back.
Did it almost 3 yrs ago. Our Elec Co had a rebate plan. Cost was $7,000, of which I had to pay approximately $2500. Saves us OVER $200/mo!!! So payback for me was 12 mos!!
Last wash I bought was a complete rehab but a couple things I didn't get around to, lighting was one of them. Will be doing that soon as I have already replaced the lighting at my other locations
I bought lights over a year ago and still haven't installed them all. Replacing because old ones are too dim and use four times the electricity and give off half the light as what I'm putting up in their place.
As Ballasts Blow on my HO 2 tune 4 foot Fluorescents I am not replacing ballasts. If fixtures are good I am replacing ballasts and replacing tunes with LEDs. If Fixture is bad I am replacing with LED fixtures. LEDs last longer and are cheaper to operate.