How much combustion does a modern city need to function? Every winter, Delhi’s skyline disappears behind a familiar grey veil. We measure the smog and debate its sources, but must also examine the energy systems behind it. Vehicles and diesel generators burn fuel within the city, while fossil-fuel-based generation supplies part of the electricity used by homes and businesses. While much of this combustion remains unseen, its consequences do not. Delhi’s monitoring and emergency measures remain essential, but cleaner air requires reducing the combustion that produces pollution.
India’s renewable-energy transition creates a pathway to do so. In Delhi, the appetite for cleaner energy is already visible. India’s renewable-energy transition offers that opportunity. This year, by mid-October, applications to Delhi’s rooftop solar programme had crossed 88,000, including interest from rural areas and unauthorised colonies. These applications indicate demand, not yet installed capacity or pollution reductions. The opportunity is to turn that interest into working systems that enable citizens to build cleaner energy and, where polluting generation is displaced, cleaner air.
Delhi’s air-pollution challenge has no single source. A 2026 assessment found that transport accounted for 23% of winter PM2.5 concentrations and industry and thermal power plants 9%. Another 27% comprised secondary particulates formed from emissions linked to transport, industry, power generation and other sources. How we move, produce and power economic activity shapes the air we breathe. Therefore, clean air is not only an environmental issue, but also an energy-system issue.
Renewable energy cannot address every source, but it can reduce the combustion behind many of them. Solar and wind can replace fossil-based electricity; rooftop solar, storage and stronger grids can reduce diesel use; and cleaner electricity can power transport and industry. The benefits become particularly important where pollution and people meet: nearly one in four urban Indians lives within 500 metres of a highway.
{{/usCountry}}Renewable energy cannot address every source, but it can reduce the combustion behind many of them. Solar and wind can replace fossil-based electricity; rooftop solar, storage and stronger grids can reduce diesel use; and cleaner electricity can power transport and industry. The benefits become particularly important where pollution and people meet: nearly one in four urban Indians lives within 500 metres of a highway.
{{/usCountry}}This is why location matters. Replacing a diesel generator in a crowded neighbourhood or electrifying buses on a busy corridor can reduce combustion where people live, work and travel. Replacing fossil-based power elsewhere in the grid supports the wider transition to cleaner electricity. Both matter, but their benefits are felt differently. One cleans the air close to home; the other helps clean the system that powers the city.
The rooftop solar movement is already expanding beyond India’s largest metropolitan centres. By July 2026, Lucknow district had installed more than 124,000 rooftop systems under PM Surya Ghar, followed by Nagpur with over 100,000 and Surat with close to 94,000 installations. These are hundreds of thousands of individual energy decisions, made rooftop by rooftop and neighbourhood by neighbourhood.
Cities are also integrating renewable energy into public infrastructure. Chandigarh’s solar installations had generated more than 270 million units of electricity by May 2025, avoiding an estimated 186,000 tonnes of carbon emissions. In 2021, Surat Municipal Corporation reported renewable energy capacity of 35% of its annual electricity consumption.
These examples show clean-energy adoption across cities. Delhi’s air-quality challenge also requires coordination within its own regional airshed, because air does not follow municipal boundaries. In the winter of 2022–23, nearly a third of Delhi’s PM2.5 comprised secondary particles, such as sulphates and nitrates, with 84% of this component linked to emissions outside the city. A city may govern within a boundary, but it breathes within an airshed.
The foundations of a cleaner urban energy system are already taking shape, from household rooftops to municipal infrastructure. The opportunity is to connect these individual points of progress into a wider clean-air ecosystem.
The first opportunity is to build on rooftop solar by making cleaner air a more participatory endeavour. Households often adopt solar to lower electricity costs and gain greater control over energy use; reliability depends on how solar is combined with battery storage, grid supply and backup arrangements. Community solar, storage and cleaner backup systems can extend participation to residential associations, schools, small businesses and commercial establishments.
City authorities, distribution companies and industry can make participation practical by coordinating accessible finance and technical guidance for households, residential associations, schools and small businesses. The objective should be affordable, reliable systems that reduce dependence on polluting backup generation, not simply a higher number of adopters.
The second opportunity is to direct clean-energy investment where it could displace the most polluting combustion. Pollution boards and city authorities could help identify high-emitting areas, working with distribution companies and sector agencies to explore cleaner alternatives. Priorities might consider the fuel displaced, people exposed and cost of action, rather than pollution readings alone.
Solutions could then respond to the source. In commercial areas, solar, storage and reliable grids could reduce diesel-generator use. On busy routes, electric buses could eliminate tailpipe emissions from the vehicles they replace. In industrial clusters, electricity could replace fossil fuels in suitable processes. Progress might be tracked through diesel saved, diesel vehicle-kilometres replaced and industrial fuel displaced, while assessing local air-quality benefits separately over time.
The third opportunity is coordinated action across regional airsheds. The Commission for Air Quality Management is already developing finer-grained maps of Delhi-NCR’s pollution sources and could bring pollution boards, municipalities, distribution companies, transport agencies and industry together around shared priorities. Pollution boards could use these findings to identify priority areas, while municipalities, distribution companies and industry assess viable clean-energy projects.
Projects could be compared by fuel displaced, particulate and nitrogen oxide emissions avoided, and populations potentially benefiting. Ambient air-quality monitoring would remain essential, but no individual project should be credited with a citywide AQI improvement without evidence.
India’s energy transition is already changing how citizens, businesses and cities use electricity. Connecting this progress with air-quality priorities is the next opportunity. Success should reflect not only clean-energy capacity added, but polluting fuel replaced and emissions reduced where people live and work.
(The views expressed are personal)
This article is authored by Vaishali Nigam Sinha, co-founder ReNew.