Tohono O’odham Reservation: Energy Efficient House
Course: 22.423 - Capstone
Semester: Spring 2009
Instructor: John Duffy
Partner:Tohono O’odham Reservation, AZ
The heating demand is met by direct solar gain through window glass. The high thermal mass in adobe brick absorbs heat during the day and releases it at night, which encourages comfortable interior temperatures throughout day and night. The cooling demand is met by a systematic night ventilation schedule, which takes advantage of cooler night temperatures of the high desert. Monthly average interior temperatures were simulated for an entire year. Conservative assumptions were made to ensure the actual cooling and heating performance would meet predictions. Photovoltaic panels were used as a source of renewable energy to provide electricity to the house. A grid-tied and a stand-alone system were designed to accommodate any building location. A home design was developed to combine theoretical performance with practical functionality. The majority of the house was modeled with CAD software to be incorporate design parameters from the thermal and passive solar models. A stress analysis was performed on the structure to ensure its stability from seasonal wind loads common to the area. Building materials used in the house were carefully chosen; most of which are indigenous to the area, renewable, and provide excellent thermal properties.
The design was well received by the faculty and students at TOCC. Plans are to construct a prototype house on the new campus of the TOCC in the near future.