Condos go green

Green bona fides: Riverhouse has a geothermal system to heat and cool the building. The builders drilled eight wells through Manhattan schist bedrock to a depth of 350 feet.

Riverhouse also employs an innovative triple-pane window system, according to developer Chris Daly. In warm weather, the space between the innermost and the middle panes is vented, allowing cool air to circulate. In winter the vent closes, and the space between the panes acts as an additional thermal barrier against cold air.

Other green features: The roof is terraced with plants, which naturally reduce ambient temperatures and capture rainwater to reduce strain on the city's sewer system. Photovoltaic cells follow the sun's path through the sky and produce electricity that helps power the building's elevators and utilities.

Riverhouse also incorporates separate plumbing lines so that "gray water" (from baths, showers and kitchens) can be reused to irrigate gardens, while "black water" is treated and recycled.

The building uses co-generation techniques and high-efficiency hot water heaters. The builders used local products in construction whenever possible to cut down on fuel consumption.

Prices: From $835,000 for a one-bedroom to $8 million for a five-bedroom.

For more information: The Riverhouse