Feasibility of using silica aerogel as insulation for buildings

Abstract: For recent years, silica aerogel has attracted great attention and been extensively used in different technical fields owning to its remarkable properties in optics, mechanics, acoustics etc. especially in thermology. The thermal conductivity of a number of different insulation materials has been measured both by Transient Plane Source (TPS) and a new designed experiment−Guarded hot plate method respectively. It turns out that silica aerogel has the lowest thermal conductivity value of 0.0144 W/mK and accordingly the highest thermal resistance among all those common insulation materials which makes it a good choice in buildings insulation industry. Besides, the energy-saving and heating-cost of silica aerogel used as building insulations is calculated by the method of Life cycle cost analysis method (LCCA), and the result shows silica aerogel can help to reduce the annual heat loss of a building by 50.9% and also help to reduce about half of the annual heating costs when compared with other insulations. Due to the excellent thermal performances, however, silica aerogel has much higher selling prices (75.24 US$/m2) than the other normal insulation materials, and then a comparatively longer payback time (3.54 years) has to be taken than the other competitive solutions (0.22 years for EPS, 0.07 years for XPS, etc.). And the feasibility of using silica aerogel as building insulations is discussed.