Palo Alto's new Mitchell Park Library & Community Center will attempt a LEED Gold certification. Here's some information about its structure and construction.

1. air All Our Energy Comes From the Sun
Whether it’s coming down daily in the form
of solar radiation in sunshine or it came down
thousands of years ago and was absorbed into
the plants and organisms which became the pe-
troleum of today, our energy all started as so-
lar energy. The one exception is nuclear power
which shares it power source with the sun itself
- the atom. How we capture, control or protect
this free, natural resource has enormous impli-
cations for our sustainable future.
Maintaining a comfortable temperature and man-
aging the amount of light we use makes the ma-
jority of power we use in our buildings. Keeping
cool requires a lot of electricity if we don’t take
advantage of Nature’s own mechanisms to move
energy like evaporation, convection, irradiation
and conduction.
Sunshades, Screens and Light Shelves
The light that comes from the northern sky is diffused, even and consistent in all types of weather. Direct
sunshine, on the other hand, is always changing, can be very hot, can cause intense glare making vision difficult
and, because of ultra violet raditation that comes with the visible radiation will damage fabrics, organic mate-
rials and give people sunburns.
Light Trespass Reduction Photovoltaic Panels Natural Daylighting
The light emitted from the building after dark can be a nuisance to neigh- A 6,000 sq ft array of PV panels on The light that comes from the northern sky is diffused,
bors when lights shine laterally across property lines. Special light fixtures, the Libary’s flat roof will provide even and consistent in all types of weather. Direct sun-
shown below can eliminate this situation. shine, on the other hand, is always changing, can be very
10% of the project’s elec- hot, can cause intense glare making vision difficult and, be-
tricity needs. The panels them- cause of ultra violet raditation that comes with the visible
selves also reflect heating solar ra- radiation will damage fabrics, organic materials and give
diation away from the roof surface people sunburns.
further aiding in keeping the build-
ing cool and comfortable inside.
Nighttime Light pollution Electric Vehicle re-charging
Lights in a building and in the landscape that shine upward have the cumu- Parking spaces and electric re-charg-
lative effect of eliminating darkness in urban areas which actually has nega- ing stations will be available in the fu-
tive impacts on animal species’ sleep patterns and some birds’ navigational ture. These will be available for both
behavior. It also makes astonomy difficult hindering the scientific research employees and the public. These are
of outer space and the atmosphere. another part of an effort by the City
Raised Floor Air
of Palo Alto to encourage alternative,
Why no wind turbines?
low energy means of transportation.
Palo Alto enjoys very calm wind conditions due to its position east of the
coastal mountains that block the prevailing on-shore winds.
Conditioning
Takes advantage of the natural tendency of cool air to
fall and warm air to rise. This system circulates chilled
Cool Roofs air below the floor closer to people it’s intended to cool
rather than trying to force cold air down from ceiling
The roofs of both the Library and the Community Center will be of a bright vents with energy-consuming fans. This also allows for
reflective color to further limit the amount of heat absorbed by the sun. the flexible placement of power and data outets through-
out the floor
Mitchell Park Group 4 Architecture Research + Planning - www.g4arch.com

2. water
Water is Everywhere
Water connects us all and therefore plays a
central role in how a building and a landscape
relate to the natural forces around us. Be-
ginning with the rain falling onto the building
and site and continuing with the introduction
of recycled water, it can be harnessed to help
cool, heat & sustain the systems and spaces
in and around the building.
Many of these systems also depend upon and
provide benefits to the earth and air-related
aspects of the building.
Solar Water Heating Panels Extensive Green Roofs
Extensive Green Roofs are
lighter and require less main-
tenance than Intensive Green
Roofs. They can support a wide
variety of plant types while also
helping to clean and slow run-
off into the storm system. They
also provide valuable insulation
both from heat and the cold.
Bioswales & Infiltration Basins
As important as it is to control the buildings from overheating, there are still many needs for hot water. The sun Located in the middle of the parking
will help to raise the temperature of water to over 100 degrees, leaving very little energy needed to raise its tem- lot, these planted strips slow down the
perature to be appropriate for use in bathrooms, showers and in the kitchens. These solar hot water panels will be rate run-off flows back into the storm
on both the library and the community center roofs. drain and out to the bay. Special types
of permeable paving, engineered soils
and water-resistant plants allow the
water to slowly pass through and help
remove the pollutants the water picks
up from the air, roof and surface of the
parking lot.
Nightsky Radiant Cooling
This systems takes advantage of the nat-
ural behavior of all objects to irradiant
heat energy. This is especially powerful
at night when the sky is clear. Water
is sprayed onto the sloped roof of the Concrete and paving that allows water
library and as it runs down across the to flow through instead of across the
surface, it radiates its heat energy out- top is also cooler both to walk on and
ward faster than it absorbs heat from for the air around the building.
the roof surface by conduction. The
result is surprisingly cold water that is
then stored and used during the warm
days to cool air that is then circulated
throughout the building.
Porous and Permeable Paving
Library&
Library & Comm

3. earth
A Well Grounded Place
The City of Palo Alto and Group 4 Architects and
all the participants and supporters of this proj-
ect share the desire to create a place that is not
built and operated in a ecologically sustainable
and responsible manner, but also to contribute
to the community something that enriches the
lives of young and old alike. The most sustain-
able projects not only sustain nature, but also
sustain ourselves in learning, recreation, social
events and cultural experiences.
As all the energy used in our daily lives come
from the sun, all that we use to building and con-
sume comes from the earth. This project hopes
to communicate this truth. The materials and
landscape express this in numerous ways.
Intensive Living Roofs, in addition
Green Walls & Screens
to providing insulation, rain water
detention and filtering, they support
Intensive Green Roof a variety of plants including vegeta-
bles, lawns, trees and flowers.
One of the greatest benefits of plants on and around buildings are their simple beuaty.
Non- V.O.C. Materials Their presence also helps clean the air, control sound, reduce glare and support habitat
replacement.
The strong smell in new buildings comes from volitile organic compounds (V.O.C.s). They
are gases emitted from processed materials, glues and dyes that come out when carpets,
paints flooring and other building materials are installed and they are unhealthy. The
Mitchell Park Library and Community Center eliminates this health hazard by making use
of naturally produced and installed products.
Shade 50% of Parking Area in 15 years
The landscape design plays a very important role in managing the water treatment through
the site and contributing to the temperatures in outdoor spaces. Paved parking lots are
frequently the most overheated places because asphalt and concrete absorb and slowly
radiate heat back to the surrounding areas long after the sun goes down. By requiring
that trees are planted to shade at least 50% of the city’s parking lots, Palo Alto will assure
comfortable and visually pleasant facilities in the community.
Locally Produced Materials
Transporting materials from factory or mill to the building site consumes enormous
amounts of energy. By obtaining all the building materials and products used in the build-
ing from less than 500 miles away for Palo Alto, the project will save this energy and also
contribute to the local economies
Recycled Building Materials Energy Usage
It is often more efficient to re-use products and materials found on-site than it is to man- This diagram shows the diverse sources of energy used in this project and where they finally
ufacture, transport and buy new ones. for example, this project will re-use the concrete are used. As you can see, 10% of the electricity used in this building comes from the photo-
foundations and sidewalks of the exisiting library and community center by grinding it up voltaic panels on the roof. That’s free energy! HVAC is the top consumer of energy, so you
inito rubble that will become the rough aggregate foundation below the new driveways can see how important it is to keep cool. While this looks like a lot of energy being used, a
and sidewalks around the new buildings. Some wood from the exisiting buildings and typical building like this uses 3326.5 MBTUs/yr - 42% more energy. That’s a huge savings - and
trees that will be removed may become new architectural features inside the buildings. good for the environment.
unity Center Group 4 Architecture Research + Planning - www.g4arch.com