Indoor Air Quality
And Thermal Comfort
Excellent indoor air quality is maintained throughout the year by using
air-handling units with desiccant-based dehumidification, a dedicated
outdoor air system (DOAS), and
proper control of the quantity of outdoor air based on CO2 concentration.
The minimum quantity of outdoor air,
which is taken through the air han-
dlers, is supplied to the space above
the radiant ceiling panels. This air is
continuously returned at the floor level
and is then returned to the rooftop
air handlers. Figure 6 shows indoor
CO2 concentration data on the verti-
cal axis, which was measured by floor
and time of day when the air handlers
were in operation, and the average
temperatures of each season (summer,
shoulder seasons, and winter) on the
horizontal axis. CO2 concentration
detects an occupant’s presence, and
the power is automatically turned off
when nobody is present.
Earth-to-air energy exchange occurs
using an underground trench in the
seismic isolation layer to preheat or
precool outdoor air. In addition, well
water for direct thermal exchange is
used as an untapped natural resource
in the lower level air handlers.
Together, this zoned approach provides for a very efficient distribution
of both energy and comfort.
Other energy-reduction strategies
include active plug-load management and geoexchange. Each desk is
equipped with an electric outlet or
receptacle capable of showing electricity consumption for that desk. It
is also equipped with a sensor that
just before the operating
phase, using 400 black
lights for the heat load.