Panaji: As the state government gears up to initiate the second phase of the national Ujala scheme under which around 1.66 lakh street bulbs will be replaced by white LED bulbs, the jury is still out on whether it is the right move as experts say that the illumination required on roads is more than what white LED bulbs may provide.
Eye specialist Dr Chandrakant Shetye believes that the yellow and warm light from the currently installed bulbs is more illuminating than the proposed white light of LED bulbs. “The move is beneficial if we consider the cost efficiency factor, as LEDs consume far less energy when compared to halogens, compact fluorescent lamps (CFL) and incandescent bulbs. The iris contracts and expands to allow the amount of light to enter the eye. Yellow light is too bright and the iris cannot expand as much as needed which in turn affects the eye. The white light generated by LEDs is optimal for indoor purposes such as reading and working at a computer. Yellow, warm light that is emitted from incandescent bulbs is too bright for such purposes, but is ideal for street lighting as the illumination provided is higher,” Shetye explained.
Incandescent bulbs use a wire that lights up after getting heated by electricity. Their drawback is that only five per cent of the electricity is used for illumination and the rest is lost as heat. Also, the average lifespan of an incandescent bulb is 1,200 hours whereas a CFL and LED usually last up to 8,000 and 50,000 hours respectively.
But, CFLs, which use one-fifth of the total energy consumed by an incandescent bulb, use mercury vapours to emit light. This makes their disposal a big problem as, if not done properly, mercury can be harmful to health.
With LEDs being perceived to be cleaner and more efficient at energy consumption, the government decided to make the shift, and distribute it in households across the nation as well as use them in streetlights. The programme was initiated by Prime Minister Narendra Modi on January 5, 2015.
While the installation of the white LEDs on the streets of Goa will be done over a span of six months and would cost 90 crore, the fear is that the illumination that will be generated will not be sufficient for the roads.
“White light does not give as much illumination as yellow light. Currently, we’ve observed that white light is being installed on streets, which is not ideal. Light from a LED bulb does not diffuse into its surroundings. Yellow light should be used instead as it can provide the required amount of illumination,” said Rahul, sales in charge of major electronics firm.
While agreeing that they will install white LED bulbs, state power department officials said the policy has been implemented all over India. “Around 20 to 30 small LED bulbs will be installed in each streetlight. The pilot project has already begun near Margao and after two months, we will initiate it across Goa. The illumination is good. There have been good reviews from other cities so far and most of all, the power consumption of these bulbs is significantly less than the current street light bulbs,” said superintending engineer and nodal officer for LED bulbs and streetlight fixtures, N N Reddy.