DeSigN StrategieS for LOW
BuilDiNg EMISSIONS
Operational energy, which includes heating and cooling, has the most impact on emissions and should be a priority to address. This can be accomplished with energy-efficiency strategies and good old-fashioned passive solar. Project by P. La Roche, F. Mustieles and I. Oteiza
PaBlo la Ro CHe PH.d.
44 May 2010 SOLAR TODAY solartoday.org
Buildings are the single-largest contributor of global greenhouse gas (GHG) emis- sions. The energy used to operate buildings in the United States accounts for as much as
50 percent of total carbon dioxide (CO2) emissions and 76 percent of electricity consumed,
according to architecture2030.org. In addition,
buildings generate CO2 and other GHGs during
their construction, through water usage and in
generating waste. Transportation to and from
the buildings raises emissions even further. The
bottom line: If we are to have any real impact on
climate change, it’s critical to address emissions
from the building sector.
Fortunately, web-based carbon calculators
offer designers tools for significantly reducing
emissions in new and existing buildings. Based
on data from these carbon calculators, the chal-
assessing the Carbon-Counting Tools
a building’s carbon footprint typically is an
estimate of the carbon dioxide emissions for
which an individual building is directly respon-
sible over a given period of time. Some defini-
tions include life-cycle analysis. The Carbon
Trust ( carbontrust.co.uk) describes carbon
footprint as “a methodology to estimate the total
emission of greenhouse gases (GHG) in carbon
equivalents from a product across its life cycle
from the production of raw material used in its
manufacture, to disposal of the finished product
(excluding in-use emissions).”
Carbon footprint calculators are available
online to determine personal carbon emissions.
While not directly applicable in the architectural
design process, these calculators can assist the
designer in getting a feel for the numeric rela-
tionship between lifestyle, consumption patterns
and emissions. Most carbon-counting tools can
be used to determine emissions from energy
usage in buildings or from transportation. Some
can determine emissions due to water, waste or
construction, and a handful can even be used to
calculate the carbon impact of the food we eat.
In this analysis, our team compared several
lenge of designing a truly carbon-neutral home
is evident: Emissions from the average-sized
single-family dwelling must be reduced from
as much as nearly 20,000 lb ( 9.07 metric tons)
of CO2 equivalent per year to zero. However,
simple design decisions, from a better building
envelope to passive heating and cooling strategies, can dramatically reduce emissions — and
utility bills.
