the payback was about three years on the installation costs and the savings in electricity worked out to about $4500/month. The council argued on how to spend this "extra" money that was now available.
finally, After much discussion they decided to buy playground equipment and school book!
Change the lightbulbs and we could turn off ALL the coal fired plants!!! But heck why would we want to do that?
/sarc off!
LED traffic lights are awesome, my city is slowly converting to them as the regular ones burn out. Very bright, even in daylight, which I like.