LANDSCAPING & EXTERNAL WORKS
BEST PRACTICE FOR LIGHTING SCHEMES
When planning lighting schemes for public spaces , often the ‘ less is more ’ approach is a good starting point . The cost of overilluminating a space isn ’ t just financial . Specifiers must consider negative impacts of light pollution on wildlife , as well as on human health . Variables such as colour temperature , intensity , glare and positioning all have an effect on biodiversity .
As a rule of thumb , warmer colour temperatures (< 4000K ) are the best option where wildlife is concerned . Nocturnal wildlife relies on darkness to survive . Bluer colour temperatures which mimic daylight are a huge disruptor of circadian behaviour , in humans and wildlife , producing up to 3 times more visual sky glow .
A common myth is that LEDs with warmer colour temperatures (< 4000K ) emit a lower light output than their ‘ colder ’ counterparts . However , innovation in LED technology means this is no longer the case . In fact , in Lumena ’ s professional solar ranges , the light output between the two is equivalent . Some luminaires even come with a remote control to adjust light output to a level that suits the task in hand .
Another important factor to consider is light distribution . What IS being illuminated compared to what SHOULD be illuminated ? Light should be kept to the areas where it ’ s needed , without encroaching onto sensitive spaces such as natural habitats . Most luminaires are fitted with glare shields to reduce large , unwanted spills of light . Designs with a downward light emission are extremely beneficial , only illuminating the required surface below , minimizing both obtrusive light and glare .
Huge care must also be taken around beam intensity . A high lumen output along a busy pathway at 5pm rush hour is helpful , but the same output at 1am is unnecessary , often causing more harm than good . To combat this , dimming sequences are common practice in high-end , public lighting . For example , Lumena ’ s solar-powered path lights operate a gradual dimming sequence from 100 % at dusk , down to 30 % during the early hours of the morning . This technique not only benefits the ecosystem but also saves energy .
Specifiers and suppliers have a responsibility to keep light pollution to a minimum . Referring to a luminaire ’ s photometric data ensures a light fitting has the desired distribution and intensity . ILP member , Lumena Lights , has this data available for much of their commercial lighting , including solar path lights and solar street lights , with more on the way . Contact them today with your requirements and they will be happy to help .
www . lumenalights . com
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