Comfort Early Analysis in High Density Urban Context
This case study is also
The solar tools presented here are included in the TOWNSCOPE II software developed
by the LEMA-ULg.
TOWNSCOPE II is a computer system devoted to support solar
access decision-making in a sustainable urban design perspective.
consists of three-dimensional urban information system coupled with solar evaluation
tools (but also morphological and wind risk analysis tools not quoted here). A
special attention has been paid to numerical results interpretation which is all
arc, but trivial in complex built environments. As it is a crucial aspect in decision
making, especially for current negotiated urban design practices, these visual
instruments have been developed in order to unveil the geometrical mechanisms
lying , behind the final results.
These tools differ from the existing ones
by the attention they pay to the three-dimensional geometry of open spaces. They
effectively bring back any urban formal amendment built to the evaluation of its
impact on the quality of space in open space. The problem relates then to the
representation and the evaluation of the not-built urban form: open spaces.
preliminary stage before any solar calculation is the construction of a virtual
model of the studied site. These models can be produced very quickly because they
involve masses and the full-vacuum ratios import more than the architectural details.
According to the problem considered, one can modify the models to present various
Ground direct radiation Stanislas Place, Nancy, France
the model is completed, the data-processing tools could calculate the direct,
diffuse, transmitted and reflected energy radiation on any point or face (frontage,
portion of ground, etc) defined by the user.
On the basis of stereographical
projections, the masks of shade and thus the sunshine duration can also be evaluated
for any specified point.
Frontage direct solar radiation on June 15th Sainte-Margherite,
renewed interest of general public for the city and the quality of life downtown
has caused particularly complex passionate debates to emerge. Indeed each one
gives, without reserve, his argument and amidst these very firm standpoints it
sometimes becomes impossible to defend a point of view.
Broken dialogues, missed
urban debates, building sites stopped a thousand times, constructions demolished
before they can be exploited, licences to build cancelled, waste lands, etc. are
many alarming situations for which these tools try to give a solution. Better
management of environmental (natural and urban) resources, better participation
of the population and better information of decision makers are the underlying
Ground total solar radiation on April 15th Sainte-Margherite,
- Based on stereographical projection
for any defined point
Shade mask and sunshine duration
Based on spherical projections or any defined point and surface
Solar paths on a sterographical projection & numerical
output of solar computation (direct and diffused radiation) at on analysis
point Ilot Saint-Micel, Liege Belgium
In 1992, the inhabitants of Pierreuse neighbourhood in Liege complained to
the State Council about the supposed consequences of the Law Courts extensions
construction, and particularly their fear of being overshadowed by them.
should be known that, at end of the XIX century, the railroad opening isolated
the Pierreuse urban area from the city centre but also gave it, as an another
outcome of the important destruction, a natural sunshine and incomparable views.
Law Courts extensions project - Global virtual model
The Law Courts extension project
proposed to heal this part of the city by recreating missing connections. This
large scale project carried by a public initiative posed considerable problems,
including the appreciation of the changes the modifications would bring to the
environment. As a result of the lodged complaint, during the year, the State Control
over Public Buildings asked the LEMA-ULg to carry out a study to analyse the shading
effects of the planned building. The impact of shade masks on solar energy received
by the neighbourhood was consequently analysed and, compared with the original
situation and also with a characteristic local one (Place du Marche, Liege).
Frontage solar radiation - Pierreuse, Liege, Belgium
results were used during the lawsuit between the residents and the authorities.
The judgement concluded that "The harmful effects called upon cannot be regarded
as abnormal or exceptional in an old and significant city and, in all cases, they
do not seem to seriously compromise the quality of life of the applicants" The
lawsuit was closed and although two other complaints were lodged by the residents
the question of " Sunlight" was never on the agenda again.
Solar paths on sterographic projections calculated for
a point defined at the centre of Pierreuse's place in Liege
Solar paths on sterographic projections calculated for
a point defined at the centre of Place du Marche in Liege(benchmark data)
though this experiment is not particularly positive, it has a lot to teach us
(we also have to mention that a part of the project decreased in height during
the studies). In fact, it tends to highlight the requirement need to create a
common reference frame that will lead to a better comprehension of the situation
for the decision-makers and for all the stakeholders. Three great principles of
sustainability are in background of this experiment: citizen solidarity (whether
one is a high decision maker or simple inhabitants), precaution (to question oneself
a priori) and the participation (active of each one rather than an interminable
continuation of sterile arguments).
This experiment put in evidence the significant choice of relevant
benchmark data. Indeed, the urban development of a city, cannot be called in question
by the existence of an advantageous and exceptional situation concerning only
a very limited number of people. The judgement pronounced by the State Council
constitutes, in that, an unique case. If the solar needs and requests are obviously
different in Lisbon or in Copenhagen for example, the urban development possibilities
and the local premises layout must also be taken into account; the conclusions
could not be the same in a town Centre of the Middle Ages or in a Seventies suburban
study was commanded by the Liege's direction of the State Control over Public
Buildings following the complaint lodged by the Pierreuse's inhabitants.
the main driver of this type of research is, in fact, the numerous and complex
concrete cases met where the lack of references and rational arguments lead to
social, economic and environmentally unfavourable consequences.
Today there is a significant renewed interest for the quality of
life downtown. Buildings cannot be considered any more from simple technical and
economic points of view, the whole economic-social-cultural development has to
be considered, a sustainable balance between the exploitation of the existing
and the development of new dynamics has to be found, the large notion of accessibility
has to be explored deeper, etc...
All these ideas become fortunately come
to the forefront of planning but in practical terms the dialogue between all the
parties often remains sterile and prevents them taking all these ideas into account.
The elaboration of a pertinent content and its representation mode appears then
as a priority.
The tools have been developed to be applicable at any urban site. Of course,
the virtual model has to be constructed on the basis of each situation and we
emphasis again, the importance of relevant benchmark data to make comparison.
These indicators have already been used to analyse different situations in
various European city centres : Lisbon (Portugal), Metz (France), Nancy (France),
Arras (France), Compiegne (France), Pec (Hungary),etc
Modifications should be surely brought for typical cities where
completely new characteristics are to be taken into account (coastal cities, for
IMPACT ON SUSTAINABlLITY
Environmental: Medium (natural but also urban resources management)
Social: High (better comprehension, active participation, social cohesion)
Economic: Medium (indirect economic consequences of an harmonious development
of the city centre)
Institutional: Medium (force transversal work and participation,
state local norms and acceptable values)
Prof. Albert Dupagne LEMA-University of
LEMA-University of Liege Chemin des Chevreuils , 1 (bat 85213)
des Chevreuils , 1 (bat 85213) 4000 Liege
4000 Liege Belgium
+32 04 3669367
tel: +32 04 3669394 fax. +32 04 3669562
Albert. Dupagne@ulg.ac. be
- TELLER J., AZAR
S., TOWNSCOPE 11- A computer system to support solar access decision-making,
to be published in Solar Energy Journal, Elsevier, (1999)
A. , TELLER J. , Spherical projections as a communication instrument for morphological
decision-making in urban design CE-DG XII, COST -UCE-C4; Internal workshop on
"Groupware for Urban planning", Lyon, Feb. 1998
A., "Energyas an Environmental Criteria for Urban Planning", Proceedings of
the Seminar "Energia e Ambiente na EXPO'98", EU-CE.DG Xll-programme THERMIE, Lisboa,
A., LECLERCQ P .' La climatologie comme facteur modifiant du pro jet urbain
I Actes du 8eme Colloque International de Climatologie Publications de I'AIC,
Universite de Liege, Paris, 1995
A., LECLERCQ P .' Etude d'ensoleillement du quartier Pierreuse a Uege, rapport
public, Ministere des Communications et des Entreprises publiques, Regie des B8timents,
Direction de Liege, LEMA-ULg, Liege, 1992.
LEMA-ULg: Laboratory of Architectural
Methodology -University of Liege
to air, water and soil within the restrictions set locally and internationally?
Are the emissions decreasing?
||Is the cost/effectiveness
and/or cost/benefits of the system reasonable compared to other systems?
Compared to other needs in the city and to political goals?
||Has the planning
and decision-making for the infrasystem been done in a democratic
and participative way?
||Cost of a preliminary
||the purpose of
the case: development of a participative method to help the decision
|Is the use of
natural resources reasonable compared to other comparable systems?
Is the use decreasing? (e.g. fossil fuels, water, phosphorus, potassium)
||Are the citizens
willing to pay for the services offered? Are the services affordable
to all citizens?
||Is the function
and the consequences of the system transparent to and accepted by
the citizens? Is the system promoting a responsible behaviour by the
preliminary studies don’t use any natural resources but could
avoid a non suitable construction.
||Should be easily
affordable to all citizens (public service)
||The methods is
free of access, everyone could obtain details.
|Is the system
allowing a reasonable bio-diversity with regard to the kind of area
studied? Is the bio-diversity increasing?
||Is the organisation(s)
that finance, maintain and operates the system effective?
||Is the system
safe to use for the citizens? (hazards, health, well-being)
|Not really directly
||The cost should
not be prohibitive for public finances
|Is the system
more or less sustainable than a conventional system regarding ecology?
||Is the system
more or less sustainable than a conventional system regarding economy?
||Is the system
more or less sustainable than a conventional system regarding social