ASHRAE Journal - July 2019 - 42

2019

ASHRAE TECHNOLOGY AWARD CASE STUDIES

The LEDs were arranged in four concentric circles on the
rotunda's ceiling, creating a larger-than-life replica of the
Olympic Park's logo in the stadium's main entranceway.

The capacity of the new hot water
network was seriously tested in
January 2018 during a long streak of
very cold temperatures. Two-thirds
of the capacity of one of the three
boilers (which were downrated from
their original capacity-below in
Operations and Maintenance) was
enough to supply the stadium when
no events were taking place. This
leaves plenty of capacity to meet the
heating load during events, with
redundancy to spare.
To implement the most cost-effective, yet highly efﬁcient hot water
network, some of the cooling network coils were reused in a switchover mode to provide heating during
the winter. These coils were perfectly sized to deliver proper heating
with the low hot water temperature
from the heat pumps and ﬂue gas
heat recovery system.
All new equipment was integrated
into the existing building automation system (BAS) and a complete
recommissioning was performed to
optimize the control sequences and
systems schedules.

Ventilation Improvements

Occupancy rates at the Olympic
Park are variable, so a complete optimization of the ventilation operating
schedules and control sequences
was performed to ensure ventilation
meets the occupancy requirements

ASHRAE JOURNAL

ashrae.org

without wasting energy at other
times.
In the stadium under the spectators' seats, gas-propelled vehicles
and carts travel along an indoor
roadway that circles the playing
ﬁeld. The old-non-operational-
carbon monoxide (CO) sensors were
replaced to better supply the roadway with fresh air when CO levels
exceed 50 ppm.
For the administration and ofﬁce
areas and sports training center,
carbon dioxide (CO2) sensors were
installed in most of the ventilation system return ducts, allowing
modulation of supply air to meet
proper air quality for the occupants.
In addition, in highly variable occupancy areas such as meeting rooms,
electronic thermostats including
occupancy sensors and CO2 sensors
have been installed. This allows for
better control of air supply, taking
into account both occupancy periods
and occupancy levels.
Before the project, the aquatic
sports complex was dealing with signiﬁcant air exﬁltration that caused
major discomfort for swimmers. The
complex is located at the base of the
tower and a big chimney effect was
present. Certain access corridors
had substantial air draft inﬁltration
from outside and from other spaces
within the stadium. During the project, a survey revealed some direct
connections between the pool area
and the tower. These openings were
sealed, which increased the humidity level to the comfort zone, and also
eliminated some colder spots in the
pool area.
Finally, pneumatic controls were
converted to electronic and integrated into the BAS in all ofﬁce
areas supplied by the multizone

J U LY 2 0 19

ventilation systems. It is now possible to accurately monitor ofﬁce
temperature levels and adjust the
multizone systems' setpoints accordingly, improving occupant thermal
comfort and reducing simultaneous
heating and cooling in the systems.

LED Lighting Conversion

A total of 44,000 tubes were
converted to LED in an extensive
lighting retroﬁt, which included
the underground parking lots (over
4,000 spaces) and the entire stadium, aside from the main playing
ﬁeld lighting. This generated energy
reductions of 70% while improving
the light intensity and uniformity in
many areas.
The stadium's rotunda has a central skylight that supplied ample
natural light. Counterintuitively,
this proved to be a problem: the
natural light was often intense,
making the surrounding artiﬁcially
lit areas appear much darker in
comparison. Rather than installing
new LEDs with exceptionally high
outputs, the project team decided to
offset this effect by adding shading
to the skylight to better balance the
indoor light intensity. This meant
that lower intensity LEDs could be
installed while still improving the
visitor experience.
Areas of the rotunda used for carrying out security checks before
events were designed with adjustable light intensity to provide additional clarity when required.

Operation and Maintenance

The measures were designed to
simplify operations and maintenance for the Olympic Park's staff. In
the lighting conversion, for example, the new converted ballasts use

https://www.ashrae.org/

ASHRAE Journal - July 2019

Table of Contents for the Digital Edition of ASHRAE Journal - July 2019