Bounds Green Light Maintenance Depot
When Network Rail decided to refurbish the high bay lighting at its Light Maintenance Depot (LMD) in Bounds Green, London it opted for Holophane's Prismalume luminaires and HOLOS 2 digital controls. This combination gave Network rail significant saving in energy consumption, compared to the previous lighting, combined with a vastly improved lighting scheme and greater visual comfort for the workforce - with the added advantage of extended lamp life.
Bounds Green LMD had a long association with Holophane and originally installed a Holophane high bay lighting scheme some 25 years ago. About 5 or 6 years ago this lighting was replaced with a low-cost product under a design and build contract.
This installation proved to be inadequate for the depot's needs and another refurbishment was initiated using Holophane luminaires and controls.
The Holophane solution
Prismalume luminaires
The Prismalume high bay luminaires now installed at Bounds Green LMD use a unique prismatic glass reflector that both reflects and refracts the light to achieve efficient distributions. Key benefits include:
- High light output ratio of up to 95%
- Tailored light distributions enabling the use of fewer luminaires, reducing capital cost, installation, maintenance and energy costs
- Enhanced visual environment
- Superior vertical illuminance
- Optional versatile controls (see below)
Advanced control
Bounds Green LMD is also making use of Holophane's Optimised Lighting Operating System (HOLOS 2), which enables full control of high intensity discharge light sources.
At Bounds Green this functionality was initially used to dim the lighting in relation to natural daylight levels and variable daylight levels as rolling stock enters and leaves the depot – based on assumed reflectance's.
However, when the rolling stock livery began to change from dark blue to bright silver (during the commissioning phase) there was a significant effect on the reflected lighting level monitored by the photocell– with no way to predict which livery might enter the depot at any time. So a re-think was required.
Thankfully the inherent flexibility of HOLOS2 enabled dimming and raising light levels to be linked to presence detection, rather than reflectance's, using Holophane's dual purpose photocell/PIR sensor.
The Holophane solution for Bounds Green LMD has created a highly responsive and significantly more efficient lighting installation with an improved visual environment for the workforce.
Whereas the previous lighting was simply 'on' for 24 hours a day, the new Holophane luminaires are able to respond automatically to changes in demand at a very local level.
For example, only around 25% of the track is in use at any one time, requiring maximum light levels. Therefore approximately 75% of the track is only illuminated to the minimum requirement of 50%, for security and safety. This results in an approximate 38% reduction in power consumption, compared to uncontrolled lighting.
In addition, the use of high efficiency luminaires, with advanced controls, ensures that high lighting levels are only used where they are needed while using high frequency electronic ballasts has the added advantage of significantly extending lamp life and reducing luminaire maintenance costs.
This project, we believe, illustrates the importance and added value to the end client, tailoring a lighting design to meet the specific needs of the project while providing the inherent flexibility to respond to changes – even at a very late stage of the project.
This prestigous project has been shortlisted for a Lux Live Award - Ecolight 2011, please visit our Events page for more information.
Visit the Prismalume S product page
Visit the Holos 2 product page
Visit the Events page to find out more about the Lux Live Awards
July 2011
