Audubon Nature Center goes off-grid in Los Angeles, receives
highest LEED certification.
From Floor to Ceiling, Audubon Center at Debs Park in Los Angeles
Makes it Easy to Be Green
[ed note: read about the solar thermal cooling system further down
Los Angeles, CA, January 13, 2004 The National Audubon Society
is getting the new year off to a green start. The conservation
organization announced today that the Audubon Center at Debs Park
in Los Angeles has been certified as the nations most environmentally
friendly building. The Audubon Center received a Platinum Rating
the highest possible from the U.S. Green Building
Council, the nations leading authority on sustainable building
The Audubon Center at Debs Park is the first building in the nation
to receive the Platinum Rating under the Councils new LEED
(Leadership in Energy and Environmental Design) Green Building Rating
SystemTM 2.1. The achievement catapults Audubon to the head of the
pack of southern California buildings seeking LEED ratings, as well
as ahead of other buildings that were certified as Platinum under
LEEDs earlier, 1.0 pilot version.
Interior courtyard view: The solar panels on the
roof of the Discovery Room are visible. The Audubon Center at Debs
Park runs entirely on solar power, including heating, cooling, and
electrical systems, computer equipment, and the fountain in the
foreground. The building is the first in the City of Los Angeles
to function entirely off the electrical grid.
The design of the Audubon Center at Debs Park focuses on a number
of key environmental issues that are at the heart of sustainable
building, including renewable energy sources, water conservation,
recycled building materials, and native landscaping. The 5,023 square-foot
building is the first in the city of Los Angeles to be entirely
powered by on-site solar systems functioning entirely off
the grid. The building also uses significantly less water
than a conventional building of its size.
Audubon has been a leader in conservation for nearly a century,
said Jerry Secundy, executive director of Audubon California. The
Audubon Center at Debs Park continues that legacy. As our nations
cities and population grow, the environmental and economic advantages
of sustainably designed buildings will become increasingly important.
The role of the Audubon Center as a model of green architecture
will only grow more significant in years to come.
order to meet the requirements for the Platinum Rating, a building
must earn a minimum of 52 sustainability points out of an available
69. Points are awarded for everything from site selection and materials
used, to innovative design and indoor environmental quality. The
Audubon Center at Debs Park earned 53 LEED points, garnering particularly
high marks for its efficient water system, and renewable energy
In a city like Los Angeles, embracing sustainable design
is one of the most responsible actions you can take, said
Christine Ervin, President and CEO, U.S. Green Building Council.
As a premier example of green architecture, the Audubon Center
will provide inspiration and guidance for others looking to go green.
While energy and water conservation are major green features of
the building, Audubons commitment extended way beyond those
requirements. Virtually every aspect of the Audubon Center at Debs
Park from the floor to the rooftop was crafted to
adhere to the stringent LEED 2.1 requirements. Recycled materials
were used wherever possible, included melted down handguns and scrap
metal in the rebar that strengthens concrete blocks and floors.
The use of organic materials was also key, and is demonstrated in
everything from the carpeting of Mexican agave plant, to wheat board
and sunflower board cabinets and desks.
The LEED program also stresses the importance of using locally
harvested and manufactured materials, including wood, landscape
plantings, sheet metal, concrete, and paving materials. More than
25 percent of the building materials used in the Audubon Center
were locally harvested, and more than 50 percent of the materials
were locally manufactured in both cases an amount 2.5 times
that required to achieve LEED credits.
Located just ten minutes northeast of downtown Los Angeles, Ernest
E. Debs Regional Park is 282-acres of urban wilderness. Debs Park
hosts coyotes and 138 species of birds, yet is surrounded by some
of the citys densest urban neighborhoods. Within two miles
there are 50,000 young people, predominantly Latino, for whom the
park and The Audubon Center will provide a lifetime of outdoor discovery.
Audubon assembled a team of Green Building Council affiliates to
bring the Audubon Center at Debs Park to life. The building was
designed by EHDD Architects, and built by TG Construction. The LEED
documentation and submission was handled by Soltierra, LLC. BOVIS
Lend Lease acted as owners representative, and more than twenty
other firms provided design and construction services. Campbell
and Campbell created the architectural concept and landscape architecture
designs. The U.S. Green Building Council is the nations foremost
coalition of leaders from across the building industry working to
promote environmentally responsible design and construction. The
LEED rating system is a voluntary, consensus-based national standard
for evaluating high-performance, sustainable buildings.
Photovoltaic System: Solar Webb, Inc., a Kyocera Solar authorized
dealer, installed a photovoltaic (PV) solar system incorporating
208 Kyocera KC-125G solar electric modules, which generates up to
26 kilowatts of solar power. The system is engineered to provide
100% of the Audubon Centers electrical power needs.
Solar thermal cooling system: SUN Utility Network, Inc. and Bergquam
Energy Systems installed a 10-ton solar thermal cooling system.
The system, believed to be the first commercial solar air conditioning
system in southern California, is capable of providing air conditioning
and space heating for the Debs Park Nature Center, the National
Audubon Society's flagship urban nature center. Solar energy will
provide 100% of the power to the buildings on the site, and the
facility will operate entirely free of the city's power grid.
For photos of the Audubon Center at Debs Park, please visit:
Solar-Thermal HVAC Technology Debuts in Los Angeles at new Audubon
Urban Nature Center
Wright, Communications Director, SUN Utility Network 2004.2.3
Scant months after the Great Blackout of 2003, the Audubon Society
unveiled in Los Angeles a demonstration site of a prime solution
to the problems of the shaky electric grid and the relentless demand
for electric power: solar-absorption air conditioning, a technology
that runs completely on the free energy of the sun.
The Audubon Society has chosen Los Angeles's Ernest Debs Regional
Park, northeast of downtown L.A. and overlooking the Pasadena Freeway
(the first freeway built in the United States), as the site of the
organization's first urban nature center. The $15.5-million park
project will create the Los Angeles Audubon Nature Center on a 16-acre
parcel, which will house nature exhibits, an amphitheater and a
hummingbird garden, within the refurbished 282-acre Debs Park, which
will enjoy a new network of hiking trails leading up from the old
freeway and other new features. If successful, the Audubon Los Angeles
Nature "Discovery Center" -- a 5,026-square-foot facility
devoted to ecological experience, enjoyment and education -- will
be followed by some two dozen new urban nature centers in other
cities nationwide. The Nature Center represents about a third of
the park project's cost.
use of a fully solar-powered air conditioning system in a new urban
nature center meets several goals of today's broadbased environmental
movement, including the encouragement of clean energy technologies
and a greater big-city presence that brings nature to people who
cannot easily leave the cities to travel to nature. The Audubon
Nature Center, according to the solar AC system's designer, James
Bergquam of Bergquam Energy of Sacramento, will be the first completely
solar-cooled building in southern California and one of only a handful
in the world, the others being in Sacramento (where Bergquam has
built two demonstration systems), Germany, Japan and China.
The new $90-thousand, 10-ton Los Angeles system utilizes an 800-square-foot
array of 408 Chinese Sunda vacuum tube solar collectors, six-and-a-half-foot
(2,000 mm)-long and nearly four-inch (100 mm)-diameter glass tubes,
each enclosing a copper heat pipe and an aluminum nitride absorber
plate (with a selective coating) that absorb the solar radiation.
The Sunda tubes operate on a heatpipe principle: low-pressure water
always present inside the tubes is heated to a vapor that flows
up to the copper condenser section of the tube, a sleeve that protrudes
from the condensor section of the internal heat pipe. This heats
water flowing through the manifold that connects all of the tubes,
transferring thermal energy from the collectors to the 1,200-gallon
insulated high-temperature hot water storage tank. When the stored
water reaches a minimum of 180 degrees F. (it can reach 192 degrees
F.), hot water from the tank is pumped through the generator in
a Yazaki 10-ton single-effect absorption chiller. A lithium bromide
salt solution in the chiller boils and produces water vapor as a
refrigerant that subsequently is condensed; its evaporation at low
pressure produces the cooling effect in the chiller. This is transferred
to the interior of the Audubon Nature Center by chilled water that
is pumped through the evaporator in the chiller and then through
fan coil units in the building. The internal air in the building
is blown across the coils that contain the chilled water, providing
the interior cooling.
The system also will provide space heating in the winter on any
days cool enough to require that, and hot water throughout the year.
The 10-ton absorption cooling system costs approximately $90,000
or $9,000 per ton.
The third main component in the system is a Marley cooling tower.
For the chiller, the nominal generator temperature is 190 degrees
F., the cooling water inlet temperature is 85 degrees F., and the
chilled water outlet temperature is 48 degrees F.
A small amount of electricity is required to run the pumps that
move the chilled water and hot water, and run the fans -- and this
too is completely solar-powered, with some of the electricity from
the new center's 25-kilowatt (kW) solar-photovoltaic system (more
than 200 crystalline-PV panels) and battery bank that also powers
the building's lights and electrical equipment.
The most significant aspect of fully solar-powered air conditioning
is its capability of providing the service most in demand on the
very hot days that most tax the electricity grid without using the
grid: interior cooling. The same high solar insolation and hot weather
that makes air conditioning the greatest contributor to peak electricity
demand (and the occasional subsequent brownouts and blackouts) provides
the greatest amount of energy to the solar AC technology. "The
matter of peak-load power demand should be a top priority of every
politician following the wake-up call of the big blackout of 2003,"
suggested Ken Bergquam, a member of the Bergquam Energy team, as
he looked down from the nature center's roof as he and two colleagues
neared the completion of the Audubon installation.
The unique aspect of the solar air conditioning system is that
it displaces 15 kilowatts of peak demand for a 10-ton system. The
comparative advantage over an electric compression HVAC system is
that the energy is paid for upfront as part of the package; therefore,
the Center is not affected by rising peak-demand energy cost. The
Audubon Center's electric energy cost rates are fixed for the life
of the system -- the energy is free. The system uses only .4 kW
per ton of electricity to operate compared to the 1.6 kW-per-ton
electricity consumption of compressor-type air conditioning -- very
significant since air conditioning consumes 40 to 60 percent of
the energy used in buildings. An added bonus: the solar panels provide
added insulation to the roof, while also reducing the air conditioning
load by 20 percent and extending the life of the roof.
Les Hamasaki, president of SUN Utility Network of Los Angeles,
the western-U.S. distributor of Sunda Tubes, whose strategic alliance
with Bergquam brought the solar AC technology to Audubon's attention,
elaborated, "Peak-load demand is the critical part of assuring
reliable energy supply, and air conditioning is the critical part
of peak demand. The only thing connected to the grid here at the
Audubon Center is the water, necessary to conform to the local fire
regulations. The key to energy security is distributed, onsite self-generation;
this will make our state and country more independent from rising
energy costs and will lessen the load on the electric grid. The
public sector should be an integral part of the overall 21st-century
strategy of solar energy as the backstop of the traditional electricity
"Solar thermal, especially used for air conditioning, should
have a buydown rebate similar to the solar electric photovoltaic
buydown program. When comparing the cost of solar-electricity versus
solar-thermal air conditioning, one producing electricity and the
other displacing the electric load, solar AC would come out as more
cost-effective even without rebates," Hamasaki continued. He
has proposed to the Los Angeles Department of Water and Power that
solar air conditioning, since it displaces peak load demand, should
receive the same rebates as photovoltaics. "The same 15-kW
photovoltaic system would cost approximately $150,000 or $10 per
watt installed. The 15-kW displacement achieved by use of solar
AC costs approximately $90,000. With a $6,000-per-kW rebate, or
80% of the installed cost, the system would cost only $18,000."
Bergquam Energy in Sacramento has used other kinds of solar collectors
for solar HVAC applications, including a 1,600-square-foot array
of flate plate solar collectors driving a 10-ton single-effect absorption
chiller on a 10,000-square-foot commercial building, in continuous
operation since 1985, and a 1,200-square-foot array of parabolic
trough, one-axis tracking collectors driving a 10-ton single-effect
absorption chiller on an 8,000-square-foot commercial building,
installed in 1995 on a contract with the California Energy Commission
(reinforced since 1998 by the addition of a 1,100-square-foot array
of direct-flow 336 vacuum-tube collectors). Bergquam's experience
with these collectors has demonstrated that the direct-flow vacuum
tube solar collectors are the superior technology for solar HVAC
applications, offering a combination of high-efficiency, simplicity
and freeze and over-temperature protection. Flat plate collectors
generally are not suitable in these applications, due to their low
efficiencies, and because their freeze protection is expensive and/or
not reliable. Parabolic trough collectors have high enough efficiencies,
but their tracking mechanism is an added expense, and there are
maintenance and service requirements for both the tracking device
and keeping the reflecting surfaces clean. A nice feature of the
vacuum tubes is that they can be removed and replaced without affecting
the operation of the array.
The Audubon Nature Center has just received from the U.S. Green
Building Council (www.usgbc.org) the highest -- i.e., the greenest
-- 'Platinum' LEED rating for "Leadership in Environment and
Environmental Design." The Audubon Nature Center in Los Angeles
is a U.S. Green Building Council LEEDTM (Leadership in Energy &
Environmental Design) 'Platinum' building, because it is 100% solar-powered,
uses 80% less water than a conventional building of the same size,
incorporates an on-site waste water treatment system, and utilizes
other sustainable technologies, strategies and designs, including
passive solar "bioclimatic" architecture. The Audubon
Center is located at 4700 North Griffin Avenue in Los Angeles (use
the Ave. 43 exit of the 110 Freeway between downtown Los Angeles