From The Wall Street Journal...
"Vornado Realty Trust, the largest owner of office property in the Pennsylvania Station area, is set to cut the ribbon this week on the city's largest power cogeneration plant.
Three yellow engines the size of small locomotives have been installed in the building. For the past month, they have been pumping out 6.2 megawatts of energy an hour, or enough to fulfill half of the energy needs of Vornado Realty Trust's 57-story skyscraper at One Penn Plaza.
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The new plower plant, on the skyscraper's 12th-floor setback, consumes natural gas to produce electricity, and then uses the byproduct of that process—heat—to fuel the building's boilers. It allows One Penn to be relatively energy efficient, and far less dependent on the city's sometimes unreliable power grid. Vornado executives also hope it will help attract tenants interested in burnishing their corporate images by locating in "green" earth-friendly buildings."