Since the 1970s it has become common practice for lights to be left on whenever trains are in service. This removed the need for guard control and allowed the use of fluorescent tubes, which have a long start-up time. However, many trains have large enough windows to allow sufficient ambient light to enter the vehicle which means lights are on only to cope with tunnels and bridges. There is therefore the opportunity to make savings if this issue can be addressed.

Porterbrook Leasing Company Ltd (“Porterbrook”), working with EAO and supported by LED supplier MARL has now addressed this issue by fitting a 3-car class 323 unit with Bright Ambient Sensing Interior Lighting or BASIL for short. 323 205 is now in service with LED lighting which adjusts its output depending on the ambient light level. LED technology offers lower power consumption for lighting and a very long “bulb” life such that they would only require replacement once in the vehicle life. Dimming the lights to only 7 watts per fitting when they are not needed means the life of the LEDs is extended so they will now last the life of the vehicle.

The objective of this trial is to prove the system which will then be available for sale across any suitable fleet. A trial was essential to arrive at accurate energy saving figures and to test public reaction to the new light colour. The prototype installation can be adjusted to optimise the savings while causing no disturbance to the passenger. This is because the Marl Saloon Ceiling Lighting or ‘Sci-Light’ system is constantly monitoring the ambient light level through the vehicle with sensors that operate independently of the LED lighting. Software then decides the light requirements and adjusts the LEDs accordingly. Running the train in service has shown the concept to be very successful as it takes considerable concentration to notice that the lights have changed at all. When the train enters a tunnel the lights go to bright faster than the human eye can adjust so no change is noticed.

The fleet fitting cost cannot be justified simply on electricity savings but the system has other advantages which make it attractive to the train operator.

The existing diffusers have to be taken down, cleaned and replaced regularly while the new system only requires the surface to be wiped over. There is therefore no longer the requirement to change and dispose of fluorescent tubes, along with the problem of carcinogenic waste (Mercury) which they produce. There is a significant improvement in the quality of light and passengers report that this makes them feel safer, especially on late night trains.

As a demonstration of the environmental benefit if the entire Class 323 fleet could be fitted at the forthcoming overhaul it would save 129 tonnes of CO2 per year thereafter.

These advantages mean that any train operator considering new lighting for aesthetic reasons or wishing to reduce his carbon footprint needs to consider this system. For new build there is a clear business case for specifying the Marl Sci-Light system.

Photographs are available by contacting Karen Jackson on 01332 262405 or by email to Karen.jackson@porterbrook.co.uk.