(It is
approximately equal to the amplitude of the
cyclic heat flow into the mass divided by its
surface temperature amplitude or swing.)
A good design strategy for building
orientation is to “tune” windows to admit
or exclude solar energy based on their
orientation. Generally, south-facing
windows should admit winter solar gain
and east- and west-facing windows should
exclude low-angle solar gain. Window
design strategies are discussed in more
detail later.
Another approach is control of solar gains
with motorized blinds, which are widely
used in airports, atriums and some
commercial buildings in Europe. Along
with other control technologies, such as
electrochromic coatings, motorized blinds
may soon become cost-effective. If active
solar control is taken into account in sizing
cooling systems, there may be significant
savings from reduced energy consumption
and reduced equipment sizing.