High above Harlem’s City College campus, a Solar Decathlon entry is being assembled on a rooftop overlooking the quad. Team New York, composed of students from City College’s Spitzer School of Architecture, Grove School of Engineering, and the art department are designing a sustainable house whose lifespan may extend beyond the biennial contest. The team’s “Solar Roofpod” entry addresses the problems of urban density and heat island effect while tapping into New Yorkers’ obsession with desirable real estate, namely the rooftop penthouse.

The Team New York proposal must meet the criteria for the Decathlon before delving into real estate opportunties. On a footprint that ranges from 600 to 1,000 square feet, the house must be affordable and attractive, supply energy to household appliances, provide adequate hot water, and produce as much or more energy than it consumes.

The Roofpod footprint measures 746 square feet and is prefabricated as two steel frame units. It sits on a modular frame that collapses or extends to accommodate the width of a midrise rooftop, be it a multi-unit apartment building or a cast-iron office tower. The collapsible frame distributes the weight of the Roofpod onto the buildings’ load-bearing walls while providing enough depth for containers to hold soil, thereby giving the building the potential to create a green roof. For the purposes of the contest, the frame must meet measurement regulations, but it’s easy to foresee how the system could extend to cover an entire rooftop.

The solar panels fixed one foot above the Roofpod house use both photovoltaic technologies and solar thermal collectors to provide electricity and heat water up to 150 degrees. Inside, the mechanical room measures a mere 4 feet by 8 feet, and interior details may be customized by residents. The multiple window configuration is also up to the client. While many windows may not foster energy efficiency, they’re key to making the product viable to a New York customer. “We have to consider the quality of life,” said professor Christian Volkmann, the program manager for the City College team. If mass-produced, Volkmann, said the Roofpods could cost about $250,000 each.

Inspired by New York’s water towers, which remain an important part of the city’s infrastructure and iconography, the Roofpods and their gardens are intended to help alleviate some of the strain on the city’s energy grid, though Volkman said that the surplus energy generated might only be enough to cool the average apartment lobby. If special zoning were encouraged by the city, scores of green roofs financed by Roofpods could become as ubiquitous as the city’s beloved water towers.