The Greenest Skyscraper Complex : WTC -ENERGY CONSERVATION AND PRODUCTION

One means of achieving these goals is "Daylighting"—which thankfully involves neither Bruce Willis nor Cybill Shepherd. Instead, as Del Valle points out, "if enough daylight is coming into the window it automatically dims the interior lights. It's all about reducing energy consumption. Every space within 15 feet of the facade will be equipped with dimming devices."

This practice not only benefits the WTC complex's energy consumption, but the occupants of the towers as well, increasing productivity and reducing the rate of minor illnesses, as well as promoting bone health and increase the activity of natural killer cells simply by improving the quality of light. Because humans require exposure to UVB light in order to synthesize Vitamin D, the dimming of artificial lights and use of ultra-clear glass to allow more natural light in.

When the sun isn't shining, the WTC complex employs hydrogen fuel cells to provide approximately 1.2 megawatts of power and steam turbines which, according to DelValle, "take the wasted steam that happens during steam generation and converts that into electricity."

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