New York, NY – July 13, 2012 – (RealEstateRama) — Nassau County Executive Edward P. Mangano today announced the completion of a major initiative to install energy efficient Light-Emitting Diode (LED) traffic signals at more than 1,300 intersections throughout Nassau County. The project, funded by a grant by the New York Power Authority (NYPA), will save an estimated $1.1 million annually for taxpayers.