Shine a light

Making things green and sustainable is usually an expensive process, but in some cases, the price of technology is dropping so quickly that it’s actually more cost-effective. LEDs are a good example.

I was an intern at the Massachusetts Department of Conservation and Recreation a couple summers ago, and one of the projects they undertook was replacing the incandescent bulbs of their streetlights with LED bulbs. (For some reason, the state parks system owns streetlights in Boston.) Even with the cost of installation and new materials, the agency’s electricity bill was reduced so dramatically that it made a return on its investment within the year.

There are other advantages to LEDs. For one, they last longer, which cuts down on the manpower and time to replace burnt out bulbs. Also, LEDs burn out slowly rather than going out completely, which is much safer when used in traffic lights.

Why isn’t every city doing this?

Currently, New York is testing LEDs, and even considering a redesign of the pole. NYTimes.com's Bits blog has a good summary of the advantages:

Not only will the city reduce its power usage 25 to 30 percent, but the bulbs will last 50,000 to 70,000 hours. Today’s sodium lamps are rated at 24,000 hours, which means at that point half of them are dead. The L.E.D. life rating actually means that the bulb will drop below 70 percent of its original brightness after 50,000 hours or so.

Some critics complain that LEDs don’t have the warm glow of an incandescent bulb. Whatever. It still might be a few years until LEDs become inexpensive enough to light our homes, but in the meantime, there’s no reason they shouldn’t light our streets.