Environmental Engineering Reference
In-Depth Information
account for
% of energy use, respectively. To
have no growth between now and
% and
requires that we
reduce energy consumption by
Quads out of the
roughly
.
Better building design and more effective use of
existing technologies can greatly improve building effi-
Quads projected for
-
ciency without waiting for new inventions. Here are some
examples:
Better insulation can be installed to reduce heat loss in
winter and gain in summer (most residential buildings
are under-insulated);
Window coatings are available to reduce heat loss
though thermal transmission (heat in and out is in the
infrared band and can be blocked while letting all the
visible light in);
Improved furnaces and air conditioners can be built
(furnaces are fairly good now, but there is considerable
room for improvement in air conditioners);
White roofs can reduce heat absorption in summer and
radiation in winter (they can even help cool the planet
by re
ecting some incoming radiation back into space
just as the ice caps do);
More ef
cient lamps can be used (compact
uorescents
now and solid state lighting in a few years);
In commercial buildings lighting has been almost completely converted
to
fluorescents while in residences, there are many lights left to convert.
One of the mysteries to be left to the social scientists is why the
residential sector is so slow to change since compact
uorescents save
much money. A
watt compact
fluorescent lasts about
hours
while the equivalent in light output, a
watt incandescent, lasts only
hours. Over
hours the incandescent will use about
of
$
electricity while the
fluorescent will use
. In addition, over the same
$
