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Denver Lights Up Courthouse Energy Efficiency
Constructed in 1964, the Byron
G. Rogers Federal Building and
U.S. Courthouse in Denver is
home to 11 government agencies. Its
inefficient mechanical systems, however,
were undermining GSA’s efforts to keep
its carbon footprint in check.
Supported by $147 million in American
Recovery and Reinvestment Act money,
the agency has modernized the building
to achieve an aggressive energy goal of
less than 45. 1 kBtu per square foot per
year. Hitting this benchmark will reduce
energy consumption by approximately
55% in the 620,000-square-foot structure.
Rather than raze the facility and start
anew, GSA elected for an extensive
retrofit. According to the National Trust
for Historic Preservation, building reuse
typically offers greater environmental
savings over demolition and new con-
struction projects. It can take 10-80 years
for a new facility to overcome the climate
change impacts created by its construc-
tion even with efficient operations.
This courthouse now uses high-perfor-
mance systems while retaining its historic
character. Key strategies included:
n Daylighting increased approximately
25% from the original design.
n Solar panels were installed on the roof
to offset domestic hot water use.
n The building is primarily heated and
cooled through the use of an active
chilled beam system, which uses
significantly less air than conventional
n The facility is equipped with 100% LED
By cutting energy demands in half, the
courthouse will reduce its annual greenhouse gas emissions by more than 2,908
tons of CO2, which is the equivalent of
taking 612 cars off the road or providing
energy to 266 homes.
gas plant producing the same amount of
The analysis also shows that by calculat-
ing the benefits of distributed generation
from fuel cells, the price per k Wh could be
brought down as low as 5. 3 cents, over 18%
lower than the projected price of 6. 5 cents
per k Wh associated with conventional
natural gas. With current fuel cell stacks
only lasting about two years, the research-
ers will look to improve their lifecycle so
the systems could last at least six to eight
years to stay competitive.
While natural gas is already used
to power buildings of all types, a
new study shows that adding fuel
cells could provide reliable power outputs
while improving facility energy efficiency
and reducing greenhouse gas emissions.
The cost benefit analysis from researchers at Pacific Northwest National Laboratory shows that if fuel cell lifespans can be
improved through ongoing research and
enough systems are produced to reach
economies of scale, the cost of natural gas
solid oxide fuel cells to power facilities
such as hospitals and big box retail stores
could compete with conventional systems.
The fuel cells, which produce electricity by oxidizing fuel electrochemically, are
made of ceramic materials and stacked
together to reach the needed power output.
The design from PNNL includes anode
recycling, steam reforming, and pressurization to improve the efficiency of the system.
Additionally, the study shows that the fuel
cell stack system would cost almost one-
Natural Gas Fuel Cells to Power Large Facilities
CUT TING ENERGY BY 55% at this Devnver courthouse will be achieved by a mix of daylighting, solar energy for hot water heating, chilled
beans, and LED lighting. The goal is to use less
than 45. 1 kBTU per square foot annually.
FUEL CELLS designed by researchers from PNNL that use natural gas and are designed for large
facilities such as hospitals could produce a similar amount of power as conventional sources while
costing one-third less to build and install.