Energy Efficiency Case Studies
BIGHORN HOME IMPROVEMENT CENTER
in 2000, the 43,000 square foot BigHorn Home Improvement Center in Silverthorne
was designed to be 60% more efficient than an identical building built to the
ASHRAE Standard 90.1-89. Daylighting via skylights accounts for a 79% reduction
in total lighting energy use, and works in conjunction with compact fluorescent
lights and motion sensors.
of technologies monitor and control occupant comfort. Windows on the roof and at
lower levels are computer-controlled to allow warm air to escape and cool air
in. A transpired solar collector on the south side of the building heats
ventilation air that is drawn into the building with fans. The building also
features a radiant heat floor system and widow overhangs that provide shade in
the summer. It has no air conditioning units.
The building features an energy-efficient envelope with double-layered
Styrofoam walls and R-34 insulation in the roof. A 9kW integrated photovoltaic
system can provide up to 25% of the building's total electric demand, with
excess electricity sold to the utility. While the energy-efficient design
resulted in a 10% increase in design and construction costs, the utility bill
savings will pay back the extra first cost in five years.