On a hot day, even with an air-conditioner, the air conditioner on my desk in central Delhi could barely get up to 100 degrees Celsius.
This was a city where the temperature rises to nearly 30 degrees Celsius during the night.
This is where the problem lies, says Ashish Sharma, an engineering professor at the Jawaharlal Nehru University and a co-author of the study.
“The city suffers from very low air-conduction efficiency,” he says.
The average air-con efficiency of Delhi’s central districts is less than 1%, he says, and there are many cities in India with worse air-coefficient records.
“There are many other factors that cause air-temperature variability, including the lack of urbanization, air pollution, and the effects of climate change.”
Air-conditioning in Delhi’s most polluted areas: Air-conefficiency record by district, 2014-2020.
Source: The National Capital Corporation, The India Institute for Development Research and the Delhi University, data from the Central Electricity Authority and The Delhi Pollution Control Board, as of March 2019.
The National Capital’s pollution data, released by the power regulator last year, shows that air-cooled residential buildings have had the highest air-pollution levels in Delhi.
Air-cooling is used to cool buildings that have a thermal mass of more than 3,000 tonnes.
“It’s a very efficient and cost-effective method,” Sharma says.
But for every 10 meters of insulation that air is used, there are 50 meters of air-quality monitoring equipment, he says — a huge number, but hardly enough to meet Delhi’s air-efficiency targets.
“I think we are witnessing an air quality crisis in Delhi, where the only way to improve air quality is by investing in new infrastructure,” Sharma adds.
Delhi’s government has proposed setting up more than 500 meters of solar power projects, but that is still far short of the city’s target of installing 2,000 meters of clean-energy plants by 2022.
“That’s a long way from meeting Delhi’s target,” Sharma explains.
“If we don’t invest in this, then we will end up with a worse air quality.”
Air pollution has also reached a crisis point in Delhi recently, with a record number of PM2.5 particles and PM10 particles reaching the city, according to the Delhi Polluter Protection Act, which has been signed by Prime Minister Narendra Modi.
PM2-PM10 levels have reached 1.7 billion in Delhi — a new record.
“PM2.9 and PM2,5 have been increasing very fast, and this is what is driving the current pollution crisis,” says Ashwin Kumar, director of the Delhi-based Centre for Science and Environment.
“We have to address the problem of air pollution and create a better air quality,” he adds.PM2- PM10 levels in central and suburban Delhi.
Source : The Delhi Health and Family Welfare Department, The Delhi Government and the Union of India, data by the Central Pollution control Board and the National Centre for Atmospheric Research.
In a country with a population of more of than 30 million, air quality in Delhi is among the worst in the world, with the air-transport sector ranking second behind the food-processing industry, according the World Health Organization (WHO).
Delhi has been hit by a series of major incidents, including a major fire in February, a power supply outage and a landslide in December that killed at least four people.
A power blackout in January also left many Delhiites without power.
“This is a huge challenge for Delhi,” says Sharma.
“People in Delhi need to get their homes cleaned, and clean the air is a very important thing for them.”
Delhi’s PM2 limit, a threshold set by the National Green Tribunal in February that is a benchmark for air-treatment plants, stands at 20 micrograms per cubic metre of air.
In the worst affected areas, the limits range from 10 to 40 microgram per cubic metres.
“But even if we do get the maximum air-cleaning capacity, Delhi will not be able to meet its air-health targets,” Sharma cautions.
“So Delhi needs to come up with strategies to make air-purifying technologies affordable and sustainable, and build a more effective and efficient public-health infrastructure.”
The government has also announced the establishment of a public-private partnership to address air pollution.
This will be implemented by a Delhi-headquartered public-policy think tank, called the Institute of Public Health, and is expected to have a major impact on Delhi’s future air-sustainability.
“When the institute has a large number of projects and they get a clear picture of what the public’s concerns are, then it is very clear to them that it will be a priority to take action on the ground,” says Suresh Bajaj, the institute’s executive director.
“As an institution, we