Designing Light and Air

But your building did cost more to build?
Payback period is how most people calculate it. The big factor in the Bank of America Tower is the cogeneration plant, which has the capacity to produce about two thirds of the building's annual energy requirements on-site, at almost three times the efficiency of using power from the grid. That was the most expensive technology, but the payback period, in reduced energy costs, is less than four years.

Daylight is a different factor: it costs energy, and we have floor-to-ceiling glass. There's solar-heat gain, and thermal loss in the winter. But from what we know about health and productivity, people do much better in a day-lit environment. So that's an example where you decide to spend energy to make a better place.

Isn ' t it important that the tower is close to so many subway lines?
People say, what's so green about a 2 million-square-foot skyscraper in Manhattan? The answer is that it is more green than 2 million square feet in the suburbs, because of mass transit. A subway car at rush hour gets the equivalent of 540 passenger miles per gallon. In an urban workplace, by our calculation, people use one twentieth of the energy, on average, using mass transit compared with people who drive to work.

Are architecture students today learning green design?
In the first wave, I think there was a lot of resistance in the good schools, seeing it as a kind of tree-hugger mentality. But what I see now is huge interest in the younger generation driving a change.

Aren ' t some other countries much more conscious of green building than the United States?
Yes. For example, green roofs are fairly novel here—our office in New York has one of the few. But in Frankfurt, Germany, there are green roofs everywhere. The Europeans have been way out ahead, partly out of necessity—fuel costs were way higher there—and partly culturally, because there's an idea about stewardship and investing for multigenerations. America is much more obsessed with the now. But I think we're changing very, very quickly.

© 2008