CFL Street Lights win the day
Envirolight Street light with its patented reflector system and ultra long life compact fluorescent lamps evaluated as the most cost effective technology for residential street lighting in Nelson Mandela Bay Energy Efficiency Tender
The debate about the most cost effective technology for residential street lighting was finally brought to a head in the Nelson Mandela Bay energy efficiency tender.
In an effort to maximise energy efficiency and reduce operating costs the Nelson Mandela Bay Municipality (NMBM) appointed Consulting Engineers SSI to evaluate the residential street lighting tender. SSI www.stuartscott.com have extensive experience in environmental and energy resources.
In order to evaluate all technologies on a level playing field the energy efficiency tender was drawn up firstly to ensure that the lux levels of the luminaires offered by tenderers would meet the road standards, followed by an assessment of a present value full life cycle costing over a 15 year period based on the capital cost of the luminaire together with the energy and maintenance costs
Lux levels and Road Standards Compliance
In order to prove compliance with road specifications all tenderers were required to supply a luminaire for formal testing under controlled conditions on a road at the Nelson Mandela Bay University. The lux levels at various points both up and down and across the road in relation to the pole were measured and verified. Compliant luminaires went through to the second phase evaluation.
15 year present value life cycle costing
SSI, together with Nelson Mandela Bay Municipality, should be commended on their forward thinking in deviating away from the so called scheme pricing method of evaluating tenders. Scheme pricing is completely inappropriate as a means of measurement for energy efficiency as the methodology is aimed only at the capital cost and hence does not cater for
• Luminaires utilising differing lamp technologies and wattages.
• It fails to take into account the future energy cost
• It fails to take into account lamp life and future maintenance cost.
• It bases the evaluation on the distance between poles and hence has no bearing on a retrofit program where the poles are already in situ at a fixed distance.
The following table is indicative of the present value costs of different technologies over a 15 year life cycle and is clear evidence of the failings of the Scheme price methodology which would by its nature favour lower capital cost to the detriment of the overall cost to the Municipality. In fact had scheme pricing been applied the 70Watt HPS lamp would have been selected with more than 30% greater overall life cycle cost being incurred
