TRILUX Luminaires - Proljus AB

Energy 65 % Maintenance 15 %
Investment 20 %
2.2 Portion of costs of public lighting
systems (not including structural systems
and wiring).
The cost accounting for value maintenance
(refinancing) of street lighting is based on
assumptions about the following mean life
expectancies
• 50 years for poles
• 25 years for luminaires
• 50 years for wiring systems and
• 40 years for the overall system of a
luminaire position on average.
The practical useful life is, however, considerably
longer in part, e.g. up to 40 years in
case of luminaires.
The procurement value of a luminaire position
including power supply and switchgear
varies significantly and is estimated at
€ 3,760.00 on average in Germany. Based on
a (costing-based) life expectancy of 40 years
for the luminaire position, this means a depreciation
of € 3,760.00/40 years = € 94.00
per year. In a major city with 50,000 luminaire
positions, that represents a mean
annual depreciation of € 4.7 million., which
must be covered (theoretically) by a renewal
budget. The general practice is, however,
different: On average, only € 21.00, i.e.
approx. 22 % of this needed amount, is invested
in Germany. From this it follows that the
systems have to be operated considerably
longer every year, which in turn results in
increasing maintenance costs. The conflict
can only be resolved by refurbishment
An example of road lighting in Germany Mean value
Road lighting part of power consumption 0.7 %
Part of total power consumed for lighting 6.2 %
Number of light points 10 Mio.
Connected wattage per light point 100 W
Time alight per year 4,000 h/a
Power consumption per light point and year 400 kWh/a
Annual energy costs per light point (at € 0.15 /kWh) 60 €/a
Total costs per light point and year incl. energy costs 135 €/a
Energy costs per German citizen 7.5 €/a
Calculative life expectancy
• Poles 50 a
• Cable 50 a
• Luminaires 25 a
• Lamps 4 a
Cost of a light point incl. cable and switchgear 3,760.00 €
Life expectancy of a light point 40 a
Depreciation (upkeep costs) of a light point per year 94.00 €
2.3 Example costs for street and road lighting in Germany.
measures with decreased energy and maintenance
costs (see fig. 2.4).
Costs for outdoor lighting may be reduced by
• Using lamps and luminaires with high
energy efficiency, low maintenance expenditure
and long service life, and
• Purposeful operation with regard to activation
times and the lighting level taking into
account the respective traffic situation.
125 %
100 %
75 %
50 %
25 %
0 %
Annual costs of road
lighting
Maintenance costs
Energy costs
Maintenance costs
Energy costs
Costs after
modernisation
5 10 15 20
Operating year
25 30 35
2.4 A significant increase in the annual costs due to insufficient maintenance as of the
20th year of operation and reduction of costs due to refurbishment.
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Technical information