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Solar Access: Using the Environment
<br />in Building Design
<br />By Mary-MargaretJenior, alcr
<br />More new buildings are energy efFicientthat at any time in our history..
<br />Yet most do little to use the environment in or-
<br />derto reach their real performance potential.
<br />About qo percent of our"end-use energy
<br />demand and overtwo-thirds of electricity
<br />demand is for buildings. A significant portion
<br />ofthat demand can be met usingthe sun if
<br />we team to design and renovate buildings
<br />to take advantage of access to solar energy. ,
<br />Further, buildings now produce about goper-
<br />cent of U.Scarbon emissions, another reason
<br />to take advantage ofsoler power.
<br />We know that more solar energy falls
<br />on our roofs than is required to meet the
<br />U.S. demand for electricity. However, our
<br />land-use policies and regulations discour-
<br />agethe use of this valuable resource. We
<br />need to do everythingwe canto encourage
<br />decision makers, the building industry,
<br />and building owners to think of buildings
<br />as energy producers. For our future well-
<br />being it isessential that we consider energy
<br />production and use as an integral partof
<br />building design for new construction and
<br />renovations alike. We needfo encourage
<br />builders, developers, designers, engineers,
<br />and owners to use the environmentto heat,
<br />cool, ventilate; daylight, and power our
<br />buildings. As planners we need to help edu-
<br />cate and promote changes in how we design
<br />and renovate buildings and to use land-use
<br />controls to enable that to happen.
<br />It can nolonger be an either-or choice
<br />between environmentally sensitive building
<br />design ordense developmentto achieve
<br />viable transit systems. It can and must be
<br />both. We cannotfavorone approach to re-
<br />ducingenergy use over another in making
<br />recommendations todecision makers. That is
<br />because the dominate fuel sources for build-
<br />ingsand fortransportationdiffer. At present,
<br />most energy for transportation comes from
<br />oil or biofuels. In contrast, coal is the primary
<br />energy source for buildings-with some riatu-
<br />ralgas, hydroetectric,nuclear, and wind sup-
<br />plemeotingthe grid. Of these energy sources,
<br />only hydroelectric, nuclear, and wind energy
<br />do not contribute carbon emissions. Concen-
<br />trated solarthermalplants may begin provid-
<br />ingelectricity Inthe nearfuture.
<br />According to Energy Information Admin-
<br />istration zoos survey data, an office build-
<br />ing uses about qo percent of its energy for
<br />heating, cooling, and ventilation; 3o percent
<br />for lighting; and t6 percentfoF office equip-
<br />men[ and other"plug' loads. A commercial _
<br />building built to American Society of Heating,
<br />Refrigerating, and Air-Conditioning Engineers
<br />(ASHRAE) Standard go.i (a standard com- .
<br />monly referenced in building codes) may use
<br />about zo percent of itr energy for heating
<br />and cooling, up to 7o percent and sometimes
<br />more for lighting, and the remaining for hot
<br />water, pumps, and equipment. Atypical
<br />home may use one-half its energy demand .
<br />forspace conditioning (heating, cooling, and
<br />ventilation), zo percent each for refrigeration
<br />and hot water, and the remainder for appli-
<br />ancesand electronics.
<br />It is crucial thatwe use all the opportuni-
<br />tieswe tan musterto design buildingsto meet
<br />their energy needs. We must begin to think of
<br />buildings~as being net energy producers-that
<br />is, buildings that can put energy into the elec-
<br />[ric grid insteadofjusttakingitout.
<br />How do we achieve such buildings?
<br />We begin by minimizingthe energy load pf
<br />the building itself. This is done by using ef-
<br />ficiencymeasures to conserve energy and
<br />.passive solar design strategies and other ~_
<br />solartechnologies to produce energy.
<br />The objective of passive solar-or.
<br />whole-building-design is to capture the
<br />natural environm ent using elements that
<br />are already employed in buildings and to
<br />do so at little or no increase in construction
<br />or renovation costs. The resulting buildings
<br />are more economical to maintain, aestheti-
<br />callypleasing, comfortable, and healthy:
<br />They are lightand airy, easierto sell and
<br />rent, and pleasant places to live, study, and
<br />work. Studies have shown that.employee
<br />absenteeism is reduced and performance
<br />improves when office buildings incorporate
<br />elements of solar design. Buildings that take
<br />advantage of solar buildi ng design are less
<br />dependent on fuel cost variations and can
<br />maintain comfort during power outages. ~-
<br />Theymay employ any architectural style
<br />desired and be of any buildingtype and use
<br />required-single or multifamily housing,
<br />institutional, commercial, or industrial.
<br />Passive solar buildings use asouth-fac-
<br />ingorientation (north-facing in the southern
<br />hemisphere) and building components (like
<br />windows, walls, and floors) to capture the
<br />benefits of the sun for heating and daylight-
<br />ing,and they use natural airflows and tem-
<br />perature gradients (the difference between
<br />daytime and nighttime temperatures) for
<br />ventilation and cooling.They use landscap-
<br />ingand overhangs for shading. In some
<br />climates they may use evaporative cooling
<br />or cooling towers, and soon, all climates
<br />may be able to adopt evaporative cooling
<br />technologies because of new research on
<br />desiccant technologies (materials capable of
<br />removing moisture from the air).
<br />Once the building's energy need is min-
<br />imized, owners may consideractive solar
<br />thermal for domestic hot water(DHW)and
<br />auxiliary heating and photbvoltaics (P~ for
<br />electricity. Fxcess electricity can be fed into
<br />the utility's grid forothers to use. ,_
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<br />ZONINGPRACTICE yso -
<br />PMERICAN PIANNING AGSeCIAiIONlpagea
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