Final Report Lot 9: Public street lighting - Amper

perception of comfort according to: local climate (warm, cool, rainy, snow,..), colour of street
surrounding buildings, ...
Examples:
• CIE defines a chromaticity diagram and provides a sense of the visual appearance of the
light sources and an indication (colour temperature) of how visually a 'warm' or 'cool'
lamp appear (1976 CIE chromaticity diagram).
• (IEA (2006) p. 106): 'Lamp sales around the world reveals an apparent user preference
for 'cooler' light sources the closer the illuminated locations is to the equator.
• The high energy efficient High Pressure Sodium lamp have a warmer (gold) colour
compared to the energy inefficient High Pressure Mercury lamp ('cool white').
3.3.4 Lack of skilled work force
The proliferation of more advanced lighting energy saving techniques can require additional
skills that people responsible for design and installation might be lacking.
Examples:
• Especially lighting energy saving techniques where complex telemanagement
technologies are used (e.g.: traffic density and weather related dimming, fine tuning of
maximum power point according to real street lighting surroundings, special lamp
versus ballast requirements, ..).
• Optic systems that require fine tuning related to the real surroundings.
• Calculation programs, ‘easy to use’, give the impression that anybody can design street
lighting installations. This fact hides the lack of design skills, discernment and scrutiny
on the results.
• When urban architects are more involved in street lighting they need technical lighting
designer skills.
3.3.5 Influence of the road reflection on luminance
Description:
CIE 144(2001): Road surface and road marking reflection characteristics
Scope:
The luminance of the road surface depends on the optical characteristics of the road
surface. They are defined in standard CIE 144(2001) on 'Road surface and road
marking reflection characteristics'. This standard is required to calculate the luminance
value from illumination conditions for various types of surface. Please note also that
real road reflection can vary strong on local conditions (dust, wet, ..) from -40 % up to
60 % (Memphis project (2006)).
Applicable parameter:
Average luminance coefficient (Q0) as defined in CIE 144: 'A measure for the lightness of a
road surface being defined as the value of the luminance coefficient q averaged over a specified
solid angle of light incidence',
100