Sports may be the focus here, but it shouldn't be the only option. Offices, stores, restaurants, bars, hotels, and condos have to be built in conjunction with the ballpark. The community is part of the design, giving the area as much life on nongame days as it has during a match.
NO PARKING ZONE
Noticeably absent: parking. Last year, 53% of visitors to Washington's Nationals Park came via the Metro, a trend that's expected to grow. Ideally, residents park off-site and ride light rail (or maglev trains, in this rendering), allowing better -- and more revenue-generating -- use of space than parking lots.
LET THERE BE LIGHT
A kinetic roof of strong but lightweight fabric will reduce the amount of energy -- and cash -- needed for arenas to use their retractable roofs. When closed, the space is insulated yet still lit, thanks to the translucent fabric. The stadium of the future also must be green: The photovoltaic roof generates electricity.
One minute you're looking into the stadium through large glass windows; the next, you're seeing a replay of that home run you just heard on a 120-foot-wide screen. The translucent LED screen will be built into the glass itself, allowing a seamless transition from window to display. Super Bowl party, anyone?
IN AND OUT
As field technology improves, movable turf will catch on. (An early example is already in use at Arizona's University of Phoenix Stadium.) And as seasons change, so do sports. Modular platforms like the tennis courts and skate ramp seen here can easily move and slide in and out of the space, giving the venue superior flexibility.