Tunnel illumination of the newly-inaugurated Mumbai Coastal Road Project (MCRP) – India’s first undersea road tunnel – was undertaken by Bajaj Electricals. We have Rajesh Naik, Head – Lighting Solutions Business, Bajaj Electricals Ltd, in this freewheeling conversation with Venugopal Pillai, taking us through the finer details of this landmark project. Naik discusses the execution challenges, whilst asserting that the successful commissioning of this project has empowered Bajaj Electricals to undertake even more challenging and complex projects in future.
In what way is the Mumbai Coastal Road Project unique to Bajaj Electricals?
We have been doing tunnel lighting but, frankly, the Mumbai Coastal Road Project was the most complicated project for several reasons. For one, this was the first submarine (under-sea-level tunnel project done completed us. Secondly, it presented unique constraints stemming from its unconventional geometrical features.
When you approach the tunnel, there is a sky roof. Then, you have a rectangular roof surface and then the circular tunnel. In all these different orientations, we had to maintain the lux (luminosity) levels – we had to consider the disparate light reflections between rectangular and circular surfaces. Similarly, while exiting the tunnel, we needed to maintain the lux level. This is mainly because with the changing in lighting in the tunnel and the bright sky in the day, it is crucial to enable drivers’ visual adaptation.
For instance, the light reflection from a rectangular surface will be very different from that of a circular surface. We had to think about all these factors before deciding on the precise lighting products to be used.
To maintain the same lighting effect for different geometries was the real challenge, but we could successfully overcome it!
For the MCRP, we have gone for Tunnel Sync Suite (TS2) logic”. For instance, we illuminated the Mumbai-Pune Expressway that has a number of tunnels. In this expressway, we could make do with standard illumination technology as the tunnels were much shorter in length. In the Mumbai Coastal Road Project (MCRP), we used tunnel sync suite (TS2) addressing issues like varying the lux levels depending on the time of the day (natural illumination) or depending on the vehicular traffic at a particular time, etc.
To implement this innovative approach, we collaborated with a Slovakian firm renowned for their expertise in the field and their comprehensive range of tunnel lighting solutions. However, we did not deploy the full suite of solutions as it was not expected in this project.
What features could have formed part of the full suite of solutions?
Through the tunnel sync suite (TS2) of our Slovakia-based partner firm, one could potentially integrate the PA (public address) system, air ventilation system, etc. The capability is there. If the MCRP project owner, which is Municipal Corporation of Greater Mumbai (MCGM), feels that more elements need to be integrated in the MCRP’s tunnel sync suite (TS2) system, it can be done.
What care was taken for safety of motorists given that there would be no natural lighting in the tunnel?
Yes, as I mentioned, the illumination requirements do change as we move along the tunnel due to its geometry. Further, is not just about the lux levels, it is also about the reflection caused by that particular portion of the tunnel. We needed to carefully understand this. For example, the reflection pattern for a concrete road will be different from that of a tar road. We also had to see the reflection coming from the surrounding, which in the case of MCRP, is the tunnel itself. All these factors were considered in great detail before arriving at the optimum solution.
Can you give us an idea of total physical size of the tunnel illumination for MCRP?
Considering the twin tunnels — north- and south-bound — we have deployed around 1,800 lighting devices.
Was Bajaj Electricals the sole supplier for MCRP’s tunnel lighting?
Yes, for the tunnel lighting scope, we were the only vendors. There are two approach roads whose lighting was handled by a different entity. For the tunnel lighting, we worked in close partnership with AECOM – the main project consultant. AECOM appointed a UK-based consultant who is a specialist in Tunnel Lighting Construction and Operation lighting. There was extensive discussion with this lighting consultant who even specified the use of certain fire-retardant material in the polymers (plastic) used in the LED lighting equipment!
UK standards are generally followed across the globe for tunnel lighting, and the MCRP also follows the same.
Do you also have an O&M contract for MCRP?
Our large projects, for instance the illumination of Delhi Metro, usually come with an O&M contract but in the case of MCRP, there is no O&M mandate. MCGM will be maintaining the tunnel lighting. However, all our lighting products used in the project come with a five-year warranty.
At what stage of project did Bajaj Electricals come onboard? Was it at the drawing board stage?
The Mumbai Coastal Road Project (MCRP) was conceptualized by MCGM around 4-5 years ago. AECOM was given the project consultancy mandate. That was the time when we started discussions with AECOM. After MCGM’s tendering, Larsen & Toubro (L&T) was appointed as the EPC contractor who offloaded the tunnel illumination contract to us.
We started work on the illumination after the tunnel was concretized. The tunnel illumination, in fact, started 3-4 months ago.
Does the tunnel illumination rely on grid power alone, or is there a back-up arrangement?
It is designed to run completely on grid power. However, 40 per cent of the light equipment is on an uninterrupted power supply (UPS), such that in an event of a grid power failure, the lighting stay on for safe evacuation and transit of motorists.
The MCRP has given us tremendous confidence and credibility that we will be able to design and deliver solutions, customized for a particular tunneling project. In India so far, tunnels have traditionally been of 1 km or 1.5 km, now we are talking of future tunnels that will be as long as 15-20 km.
Having handled the MCRP successfully, we are confident of delivering expected levels of lighting and quality for more complex tunneling projects in future.
In Uttarakhand, for instance, there are many tunnels that are coming up. We are working with project agencies from the ground-level in terms of what should be the specification for tunnel illumination.
Do you think this is the most complex project that you have handled so far?
As of now, yes! And it has given us experience and the confidence to work with consultants (or specifiers) where they (the consultants) do not have exposure to international standards. We can communicate what is required as per international standards because we have worked extensively on international lines. Such communication will increase their understanding in terms of what are the safety features that have to be considered. Having incorporated these international features, we would definitely give us an edge over competition.
How does the MCRP enhance your capabilities whilst bidding for domestic and international projects?
We are not focusing too much on international projects as there is plenty of opportunity in India, thanks to the massive infrastructure push.
Bajaj Electricals is more known for its outdoor lighting expertise, be it stadiums, roads, bridges, highways, etc. We have good presence in national highway projects by NHAI (National Highways Authority of India). Several NHAI projects are getting expanded by addition of more lanes, and we will also have tunnels coming as part of certain highways.
The tunnel illumination of MCRP gives us a big advantage. Now, we will be able to offer NHAI a complete package for highway projects comprising outdoor lighting, tunnel lighting as well as O&M.
All project photographs seen in this interview pertain to tunnel illumination of the Mumbai Coastal Road Project.
