Going green makes economic sense. Here's just one more great example. Nearly 1,600 iron light fixtures spread throughout Central Park have gotten a makeover. Inefficient metal halide lights have been replaced with LED bulbs, which use far less energy and last longer. The bulbs, designed by lighting and semiconductor manufacturer Cree, last 75,000 hours and are expected to save New York City $30,000 a year in maintenance fees.
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