Hale Zero: The Zero Energy Home
Hale is the
Hawai`ian word for home. This is a net zero energy
home. Is this possible without being slightly
unlivable, expensive, chic only to the eco-freak, and
exotic?
If we draw on the time-tested principles that made
homes livable before electricity, coupled with iconic
and efficient architectural design, and a few modern
technologies, a low or zero energy home can be
achieved. Read on for how these principles can make a
livable, economical, zero-energy home
today?
Gropius brilliantly designed the buildings to be oriented so the windows in each semi-arch face north, providing bright but indirect light all day but avoiding the “greenhouse effect” when windows get direct sun. While the semi-arched roofs face south to reflect hot summer sun and transmit little heat in the winter. The “post & arch” structure creates large open spaces which can be modularly constructed. Want a larger space? Add another frame.
These factories were abandoned in the 1980s but were quickly adopted by China’s artists because of their soaring, bright, and inspiring spaces. Today the Factory 798 complex, as shown below (complete with intact communist slogans on the ceilings), is the heart of the Da Shan Zi arts district.


Factory
798 today - restored into beautiful exhibition spaces
that preserve the original materials and
finishes.
These
concepts can be recycled and enhanced to make
beautiful, affordable LEED (leadership in
energy and environment design) qualified homes,
shops, offices - and dare we say, factories...
MATERIALS
At the heart, this is a naturally lightweight post
and beam design. The verticals can be fabricated from
recycled steel posts, reinforced concrete, or
recycled telephone poles. The roof arch beams
(rafters) can be steel or “glulam” type
laminated wood. A low-cost / low-tech. home can be
built by substituting a straight angled roof beams
at some compromise.
Because the structure is light, the foundation can be
too. It is well-suited to recycled concrete
(eliminates the
enormous amount of energy used in producing
cement) which can be colored and polished
for
attractive floor surfaces. Sustainable wood
flooring such as bamboo can be
“floated” on the foundation.
PASSIVE HEATING
& COOLING
The home is designed to eliminate the need for
heating and air conditioning in temperate and
subtropical climates via natural temperature
management. In extremely hot or cold climates such as
deserts, or high latitudes, the design will minimize
need for active heating and cooling.
Roof: The roof should be painted using reflective
and
insulative paint that minimizes heat
absorption on hot days, and minimizes heat emission
on cold days and at night.
Insulation fills the space between the roof arch
beams and a lightweight fabric dropped ceiling. For
warm regions that never receive snow, a light weight
“awning roof” of Sunbrella or similar
outdoor fabric can be suspended a few inches over the
solid roof to shade the “real” roof and
create an air gap that and reduces solar heat load by
up to 65%. (Mesh may be put around the edges of the
air gap to prevent birds nesting in the gap between
the roofs!)
The main heating & cooling mechanism is via
manual or thermostatically-controlledvent windows at
the top of the arch and low to the ground and window
treatments (e.g. blinds, curtains). Cooling is
accomplished by closing south facing blinds and
opening the upper & lower windows and creating a
convection draft through the space even if no wind is
present. The blinds and windows can be automatically
opened & closed by thermostatically controlled
small “servo”
motors.
Reversible ceiling fans cycle the air through the
space and create a cooling breeze on hot days.
In climates with extreme cold (such as Beijing),
radiant floor heat can be used.
Energy-efficient windows optimized
for the climate ensure the home
stays cool or warm.
POWER, WATER,
LIGHT
The semi-arched roof should face south to
efficiently orient solar
water heating
& electric for the building’s latitude
and time of day. In the mornings and evenings (and
in winter), the panels slide down tracks to face
the low sun, while during mid-day they move up to
face more vertically. The roof faces south which
is the optimum orientation for solar power. The
roof itself can painted using special
insulative paint that minimizes heat
absorption on hot days, and minimizes heat emission
on cold days and at night.
Power generated is stored in battery banks. Lighting
is by high-efficiency LEDs operating on a 12 volt DC
wiring circuit that eliminates losses when turning DC
from solar panels into AC house wiring and then back
to DC to power LEDs. Suspended X-shaped lighting
fixtures provide up-lighting for space and
down-lighting for tasks.
Solar heated hot water
is
stored in an insulated tank for domestic use and
space heating via radiators or in-floor pipes.
Rainwater is captured in cisterns for filtering
into drinking water and / or or gardening as we
used to do at my grandmother’s home in
London.
So that’s Hale Zero. Expect more on this topic!
What are your thoughts?