Active and passive storage

Nora Lockshin <misslockshin [at] yahoo__com> writes

>Can anyone clarify as to whether there is a consensus on the
>definitions "passive" storage vs. "active"? The terms originate in
>climate and microclimate control, but I see the term passive used
>much more often, but also in combination with using "active"
>materials such as Microchamber board, Silvercloth, zeolites, etc.

The terms "active" and "passive" do indeed draw their usage from
climate control in buildings.  In that usage, the distinction is
primarily between the use of refrigerative air conditioning on the
one hand, and a variety of "climate responsive design strategies" on
the other--where the "passive" design approaches may well
incorporate some minor active components such as fans.  The key is
that such devices consume a small amount of "parasitic" energy
compared to the energy use avoided in moderating large climate
variables.

In building design this usage is applied primarily to temperature
control, often by way of achieving enhanced ventilation and
humidification regimes, and by incorporating varying degrees of
thermal storage materials in construction.  It would therefore be
more useful if in Conservation circles the terms were refined to
"passive (or active) humidity control".  Of course, that would still
leave the problem of how much active intervention is legitimate in a
"passive" system.

Perhaps it should be remembered that in architecture there is a long
standing, but often ignored dictum: "passive architecture implies
active occupants".

Steve King
Associate Director
Centre for Sustainable Built Environments
Faculty of the Built Environment
University of New South Wales
Sydney 2052 Australia
+61 2 9385 4851
Fax: +61 2 9385 4507


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                  Conservation DistList Instance 16:32
                 Distributed: Friday, November 8, 2002
                       Message Id: cdl-16-32-002
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