Page 40 - ZEB AnnualReport 2015

AEROGEL AND ARGON INSULATION IN WINDOWS

AEROGEL OG ARGONISOLASJON I VINDUER

Nicola Lolli (NTNU/SINTEF)

To overcome the low thermal resistance technologies applied as part of the energy air through various processes and the inal
of transparent surfaces, different types of retroitting of a housing complex located product can take the form of powder (granular
multi-glazed windows have been developed, near Oslo, Norway. The triple-glazing units aerogel) or be a monolith (monolithic aerogel).
of which a wide variety are available on with argon were partially substituted with Almost all metal or semimetal oxides, such as
the market today. Triple-low-energy-glass double-glazing units with either monolithic silica (SiO ), aluminium oxide (Al O ), titanium
2
2
3
windows with low-emissivity coatings and aerogel or granular aerogel. Building energy oxide (TiO ), and zirconium oxide (ZrO ) can
2
2
argon gas illing, for instance, represent an use and GHG emissions were calculated and contribute to a gel formation. Among these,
effective energy-saving solution. However, compared for the cases with different windows the SiO -gel is the one that has found the
2
these technologies have the drawback that technologies. widest application. SiO aerogels, like the
2
they drastically reduce the amount of solar other metal oxides-based aerogels, also
radiation that passes through the glass due Aerogels are extremely innovative materials have interesting optical properties. Since the
to the use of several coated layers. This that, among several applications in a variety of pores forming the gel networks are smaller
condition can be disadvantageous at northern different ields, show very interesting insulation than the visible light wavelength (380-740
latitudes (such as in Scandinavian countries) properties in both opaque and transparent nm), aerogels can be partially transparent.
where solar radiation in winter is low in terms building components. Aerogels have the For this reason, aerogels represent the
of both hourly availability and quantity. Glazing special characteristic of being highly porous most promising solution for achieving very
with an aerogel illing has been proposed as materials. The porous structure, constituting low insulation values in transparent and
a technology capable of providing daylight, the skeleton of the aerogel, is called gel. The translucent surfaces without compromising the
with the beneit of an insulation value higher gel is a three-dimensional sponge-like network daylighting conditions.
than that of classic triple and quadruple of particles made by condensing particles that
glazing solutions. The results presented here are dispersed in a liquid solution, called sol. A multi-glazed window with low-energy coating
compare and assess the greenhouse gas To obtain the inal product from this sol-gel and gas illing has an insulation value of 0,5
(GHG) emissions of three different glazing compound, the liquid part is substituted with W/m K-1 and a g-value of 0,50. On the other
2

40 ZEB annual report 2015