High Performance Buildings Zion Visitor Center
— A Model of Energy Efficiency

The energy-efficient design of the new Zion Canyon Visitor Center and Transportation Center at Zion National Park in Utah saves money, reduces the buildings' impact on the environment, and brings more of the outdoors inside. The building and Zion's new bus transportation system debuted on May 26, 2000.

Buildings energy experts from the National Renewable Energy Laboratory, with support from DOE's Office of Building Technology, State and Community Programs, provided cutting-edge technologies for the visitor center complex—the hub of the park's new transportation system.

The shuttle bus system carries visitors from Springdale, Utah, to the new visitor center and from there into Zion Canyon. More than 2.5 million people a year visit the park, overwhelming the scenic canyon with traffic, frustrating park-goers with noise and air pollution, and damaging natural resources. The bus system was designed to relieve this frustration and enhance the visitor experience.

Most park-goers will pass through the visitor center, where energy-efficient features will save about $14,000 a year. Energy-saving measures at Zion include Trombe walls, daylighting, natural ventilation, and a passive downdraft cooltower. In addition to the energy-efficient features, much of the visitor center's electricity comes from photovoltaic (PV) panels on the roof. These solar panels convert sunlight directly into electricity, some of which is stored in batteries. Any excess electricity from the PV system is sold to the local power company. Some of the energy is stored in the batteries for use during power outages.

Trombe walls: Most of the heat for the center comes from a Trombe wall. Heat from the sun is trapped between a pane of glass and a black coating. A masonry wall stores the heat for release into the building later in the day. Daylighting: The primary source of light for the building is daylight, which comes in through clerestory and other windows. When there is not enough sunlight, the building's energy management computer adjusts electric light to provide only the amount of additional light needed. Natural ventilation: The visitor center was designed so that overhangs and the building's configuration block most of the windows from the summer sun. When the clerestory windows are open, cooler air naturally flows through the building, forcing the warmer air out. The energy management computer automatically opens the clerestory windows when the building is too warm. Passive downdraft cooltower: When natural ventilation is not enough, cooltowers reduce the temperature at the Zion National Park Visitor Center. Water is circulated over pads at the top of the tower. As the water evaporates, it cools the air. The cool air "falls" through the tower into the building.