Energy performance analysis of STILE house at the Solar Decathlon 2015: Lessons learned

West Virginia University and University of Rome Tor Vergata have partnered for the Solar Decathlon 2015 to present STILE (Sustainable Technologies Integrated in a Learning Experience), a house that merges Italian and Appalachian design concepts with innovative energy techniques. The aim of the work is the construction of a reliable and accurate dynamic building simulation model to perform a posteriori critical analysis of energy performance of the STILE house during the competition and to investigate the capability of the same house during a typical year in different locations. This was possible through the calibration of a dynamic simulation model of the house, using data gathered during the contest in Irvine, USA in October 2015. The work helped us to better understand the problems faced and to find optimized solutions that did not alter the original architectural concept. A 17% saving in the HVAC energy consumption for the period of competition was obtained by acting on shading, windows materials, and adequate floor insulation. The same model was also used to evaluate STILE behavior in different climatic conditions for a typical year. The study shows that the house has satisfactory thermal performance with mild and temperate climates, or whenever a benefit can be obtained by the use of the solar chimney.