|
|
Energy savings At an altitude of 5,280 feet above sea
level the city of Denver is subjected to
extreme cold in the winter and severe
heat and sun in the summer. As a result,
buildings have a huge need for heat in
the winter and absorb excessive heat
in the summer, which in turn requires
cooling systems to work longer and
harder. At the same time, the sun’s glare
and ultraviolet rays create an uncomfortable
and hazardous work environment.
Solar energy, a composite of electromagnetic
wavelengths, is responsible
for fading of furnishings, excessive heat
gain, sun glare, waste of energy and
skin damage.
To cope, city officials authorized the
fitting of solar control window films on
most of the City’s properties. Because
of this and other ongoing energy
conservation efforts The Environmental
Protection Agency honored the city and
county with a Certificate of Merit for
Innovative Technology.
Dr. Darryl Winer, Denver’s Director of
Utilities, supervised the project and
awarded the contract to CPFilms whose
professionals had recommended Vista
Ambiance VE 35 Low-E (low emissivity)
Film. Emissivity is a measure of the
thermodynamic ability of a surface to
absorb heat and to reflect it. The lower
the emissivity, the less radiant heat is
absorbed by glass and the more interior
heat is retained.
Additionally, the Low E
film, which eliminates 99.9% of harmful
ultraviolet radiation, to protect furnishings,
fabrics and carpets, will reject 69% of
the exterior solar energy that reaches
windows — most of which is heat —
thus yielding substantial savings on air
conditioning in the warm months of
the year.
Commenting on the selection of the
film Dr. Winer said, “We needed a film
that produced good energy savings and
which had good solar properties.
Glazing was too expensive and we
couldn’t go with an off-the-shelf product.
We didn’t want to use films that have
highly reflective properties or distinct
tinting on government buildings
because we look to blend into our
environment, not stand out.”
Vista Ambiance Film was installed as a
retrofit item on the interior of glass. The
film and installation is expected to pay
for itself through energy savings in less
than four years. By the end of 1999,
more than 125,000 square feet of film
has been installed in 60 city and county
buildings. And the film carries a five-year
warranty against thermal breakage.
“Annual savings are expected to be
$41,250 or about 33-cents per square
foot,” says Dr. Winer, “We’re big on
energy conservation out here. With
Denver’s elevation, radiation from the
sun is a big issue. The film helps
minimize that”.
|
