Metro Matters: Switch off needless lights to help Delhi sleep better

“What’ll we spot this evening?” Having already sighted multiple tigers, bears and crocs in the past 24 hours, I was pushing my luck in the rapidly fading lights of eastern Rajasthan last week.

“Something really rare,” said my host as we drove across a strip of farmland between Ranthambhore national park and Keladevi wildlife sanctuary. “I bet you never experience total darkness in your cities.”

The thought of no lights was enough to trigger momentary panic in a Delhiite like me who grew up during DESU’s blackout days. We spent the next hour walking in the fields without a torch. The glow from the crescent moon and numerous stars bathed the mustard and chilli fields. We spoke little and listened to our footsteps.

Walking that silent and dark landscape was indeed a rare experience. Even as citizens suffer from power outages, Delhi and suburbs find enough electricity to clutter the nightscape with neon billboards at roadsides, over-lit malls and buildings, and glass constructions that reflect and further magnify the effect.

Scientists call this misdirected, excessive clutter of artificial illumination ‘light pollution’. It not only interferes with astronomical observatories — making the stars less visible — but also disturbs life patterns. One would expect light pollution to be the developed world’s problem. But India is catching up on this global environmental hazard.

An international study published in Science Advances last month found that between 2012 and 2016, artificially lit areas across India have increased by 33% — over three times the global rate. The lighting growth is the most rapid in North India, the report said, linking the increase in night light emissions to rise in GDP and growing urban sprawls.

It is impossible — even undesirable — to keep large areas unlit because of the excessive population pressure in India. Well-lit streets and public places play an important civic function. They make roads safer for both motorists and pedestrians, while making citizens, particularly the women and the elderly, feel safer.

But while ensuring good visibility on the ground, we do not have to contaminate starlight. As the International Dark Sky Association puts it, “dark sky does not mean dark ground”. Shield lighting and bulb that face downwards on streets, roads, parking areas and other public places, can focus the light where it is required. It increases visibility while reducing distractions such as night glares confusing drivers or outdoor light trespassing into homes.

Our elected representatives should stop spending huge amounts of public money on installing extra-bright high-mast lights in public parks and gardens. If you live near one, you would have heard sleepless birds chirping through the night. And if a high-mast looks into your bedroom, you share the bird’s trauma daily.

Light pollution is now rated among the biggest stress factors in city life and it is not just the light outdoors to blame. Inside homes, you may turn the bedroom lights off when you go to bed but the flickering glow from your gadgets — television, set-top box, mosquito repellent, the air-conditioner etc — together emanate enough illumination to match a low watt bulb. Noise of gadgets have the same impact, ensuring that our living space is never silent.

We naturally follow the circadian rhythm, a sleep-wake pattern governed by the day-night cycle. Our bodies produce melatonin, a hormone, in response to circadian rhythm. Melatonin has antioxidant properties that induce sleep, boosts the immune system, lowers cholesterol, and helps the functioning of the thyroid, pancreas, ovaries, testes and adrenal glands. Night time exposure to artificial light suppresses melatonin production, warns the Dark Sky Foundation.

More lights also mean more demand for power. Delhi is already India’s highest power-consuming city, with the demand growing at 8% every year. The city cannot build new power plants because getting gas linkage has been next to impossible. Coal-fired plants are environmentally hazardous. As the cost of purchasing power will only grow, what Delhi needs is demand-side management.

The easiest way to reduce power consumption is to switch off the needless lights and manage the rest efficiently. The persistent smog may still not make it easy for the city’s stargazers, but reducing light pollution will certainly help Delhi sleep better.