Z E M C H 2 0 1 2 I n t e r n a t i o n a l C o n f e r e n c e
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When designing a building, the energy demand has to be reduced as much as possible
(passive strategies and energy efficiency), to keep its energy footprint (the surfaces
required for placing renewable energy generation systems) within its physical boundary.
This is important not only from an energy perspective, but from the practical design point
of view (existing building regulations), too. The development of new PV components will
have to consider the thermal features as parts of the new data-sheets.
When designing a cluster of buildings, the possible relationship between single buildings
has to be taken into account to design a Net ZEB balance for the cluster. The energy
boundary and the project boundary have to be in a close relationship which should be
from the architectural point of view not only a technical issue, but should also be
exploited as a design possibility.
It is easy to understand that in the future design as well the urban planning regulations
will have to consider the building’s energy footprint as a part of the design. It is a big shift
since the traditional architectural design is used to conceive in terms of design only the
space we live in. It does not conceive the energy requirements as an input for
architectural design, but rather a mandatory issue imposed by law.
Due to its features and potentialities, PV is to consider an indispensable technology
when design a new building, and when dealing with the renovation of an existing building
or district. Nevertheless, the use of PV has many challenges to face; among these it is
very important the ability of dealing with the design of Net ZEBs and cluster of buildings
not only at the architectural scale (energy generation in buildings footprint), but at the
site and landscape scale (on-site energy generation), too. This means considering the
cluster as a system, according to an ecological perspective.
Until now designing Net ZEBs has been possible mostly in the case of sites with a low
density, so that the available surfaces for PV can be commensurate on the building’s
energy demand. This circumstance seems to foster towards the development of new
“diffuse” cities. Nevertheless, pro and cons of dense and diffuse cities are very well
known, and it seems that dense cities present several advantages (more efficient urban
land use, transport and infrastructure). Furthermore, many European countries present
historical cities with a very dense pattern. Therefore it would be reasonable thinking of
the city and its peripheral areas as a whole system, where there is an energy generating
part (the external and diffuse part of the city), and an energy consuming centre.
Alternative solutions to the use of PV integrated or added into / onto the envelope have
to be conceived in the case of listed buildings, where no intervention is allowed on the
building’s envelope. One possible solution is conceiving the energy generation systems
as elements detached from the buildings, but in a formal relationship with them.
The authors would like to emphasize that none of these challenges can be taken up
without a trans-disciplinary approach, which overcome discipline boundaries and
barriers.
Acknowledgements
The authors of this paper would like to acknowledge all the members of IEA SHC Task
40 ECBCS Annex 52,
Towards Net Zero Energy Solar Buildings
, and the operating
agent Josef Ayoub.
References
[Bosco Scognamiglio 2005] BOSCO, A., SCOGNAMIGLIO, A., 2005,
Fotovoltaico e riqualificazione edilizia, Enea, Roma, IT, 2005.
