Arena Of The Future

SI asked SmithGroup, one of the nation's leading architectural firms and experts in ecological design, to create a self-sustaining, carbon-neutral arena (i.e., one that would not emit carbon dioxide). SmithGroup--under architect Russell Perry--came up with a complex that would be built in the downtown of a major U.S. city. The cost of constructing the 17.4-acre development, including its 20,000-seat green arena, would be prohibitive today, but someday soon, it won't be.

LAND The arena is located in an urban center for easy access to public transportation and existing utility infrastructure. There are stores at street level and an elevated park that rises from the sidewalk to the rooftop and is supported by struts and beams. Beneath the ramp, a bowling alley, a market or a movie theater is housed. The park also serves as the grand walkway to a hotel, built above the arena, with rooms that look out on the city or onto the public green.

TRANSPORTATION

There is a subway station under the arena, but no on-site parking. The waterfront has been cleaned up and redeveloped, and native trees, bushes and grasses that pull contaminants from the soil--through a process called phytoremediation--are planted along the riverbank. A pier has been constructed to house a ferry terminal, reclaiming the river as the transportation route it once was.

ENERGY Through sun and wind, the arena and hotel capture and store the energy they need. In all but the southernmost latitudes of the U.S., the sides of buildings that face south are effective receptors of solar radiation. Except for where the stores are located, the southern facade of the arena is covered in photovoltaic cells that capture energy from the sun's rays and convert it into electricity. The photovoltaic array is composed of energy-collecting crystals applied to glass. Even with the most efficient crystals, though, some of the sun's energy produces heat--a by-product that generates hot water for the arena.

The hotel forms a horseshoe around the rooftop park, which is open to the south. To maximize the capturing of solar radiation, a large array of photovoltaic collectors on the inner facade of the hotel is set on a track so that it can follow the path of the sun throughout the day. As the array passes in front of the guests' rooms, which are shaded from direct sunlight by the array, the angles of the cells change to leave the views from the rooms unobscured. At dusk the array faces the setting sun. The array is then raised above the roofline, becoming an 80-by-240-foot-wide screen on which events are projected through light-emitting diodes embedded in the surface. Fans who aren't inside the arena can watch the game from the park.

Meanwhile, the tall buildings of the city funnel wind through urban canyons of glass and steel. The hotel above the arena captures some of that wind through horizontal slots between floors of the hotel, where, within the hotel's structure, turbines await the gusts.

AIR The consistently cool temperature of the ground beneath the city is used to meet one of the greatest energy demands of the arena--cooling its occupants. Within the foundations of the arena is a labyrinth of passages lined with masonry. Air taken from roof level--well above the exhaust of the street--is sucked into the labyrinth through ducts and loses its heat to the masonry; the air continues on into the arena vent system at something close to ground temperature, about 55�. This cool air is supplied to the crowd as needed: Vents beneath the seats open when the seats are flipped down, releasing cool air and assuring a direct relationship between the number of fans in the stands and the air needed to cool them.

STRUCTURE Triangular planes of lightweight, high-strength carbon fiber cover the outside of the building. (A new method of producing carbon fiber--still on the drawing board--will capture carbon from the burning of fossil fuels and sequester it within reusable building materials such as beams.) The arena is designed to be easily disassembled, and is made out of materials that can be reused in another facility.

DRAINAGE Rain washes particulates from the air and off hard surfaces such as roofs, roads, sidewalks and parking lots. In many cities outdated storm sewers are choked by even a half-inch of rain, causing raw sewage to flow into the city's adjacent river or lake. Designed as a public gathering space, the park is carpeted in grass with the perimeter of the seating area and much of the slope up to the roof covered in native vegetation. The plants retain and clean rain as it drains off the roof. Whatever water flows from the site is stored in a pond at the base of the slope, then used for the toilets within the arena.