A survey of member cities conducted by the US Municipal Solid State Lighting Consortium has confirmed that failures after 5+ years of installed LED street lighting luminaires are less than 1%.
This compares with an HPS luminaire failure rate of 10% cited by the City of Los Angeles in support for the first phase of its city-wide LED retrofit of 145,000 street lights that it completed in 2013.
The survey, conducted earlier this year, showed that LED public lighting luminaires are meeting expectations for long-term reliability.
Of the total failures, averaging 0.96% of all luminaires, 0.16% were “out of the box” failures caused by shipping damage or other issues encountered prior to installation.
The longer-term failures (0.8%) could be divided into three causal categories:
- Human-caused failures – 19.9% (vandalism, accidents, pinched wiring, etc)
- Nature-cause failures – 8.1% (lighting strike, storm damage, etc)
- Component failures – 71.8%
The most common reason for component failures was the luminaire power supply (LED driver) which, at 67.2% of the total failures, occurred in only 0.4% of luminaires overall. Individual LEDs failing to light were responsible for only 8.3% of component failures, meaning this fault occurred in only 0.05% of installed luminaires overall.
The Municipal Solid State Lighting Consortium (MSSLC) is a US Department of Energy funded organisation with 360 municipality (council) members that combine resources and knowledge to assist with LED public lighting and controls systems deployments in US cities and towns.
Editor: The MSSLC data refers to installed luminaires that have undergone a rigorous evaluation process prior to selection, so may not be representative of all LED luminaires ‘on the market’ in the US.
This story has been reproduced with permission from the October 2015 edition of Public Lighting Today.