As heat rises, how Indian bedrooms are pushing the power grid to limits
Concrete absorbs heat to keep homes warmer at night, prompting indiscriminate AC use. The next day begins on a warmer baseline, creating a never-ending heat cycle
The number is only half the perspective; the real story is that this demand was not coming from added industrial production contributing to the country’s economy but from urban bedrooms.
For decades, India’s power load was shaped by factories and farm pumps. Of late, Uttar Pradesh, a state with no comparable industrial base, sits at the top of the demand table. Six of the top 10 demand-driving states on May 21—UP, Tamil Nadu, Bihar, Odisha, West Bengal and Andhra Pradesh—are not considered as industrial powerhouses. They are simply hot, humid and increasingly air-conditioned regions.
In Delhi, where AC penetration is the highest in the country, a discom official estimated that air-conditioning alone accounts for 30-50 per cent of the domestic and commercial power consumption.
Rapid urbanisation, which modifies Land Use and Land Cover (LULC), is behind the elevated temperatures in cities and towns; and this creates the phenomenon known as Urban Heat Island (UHI). This UHI effect translates into kilowatts of additional power consumed.
Here is how it happens: concrete, asphalt and glass absorb solar radiation through the day and release it long after sunset. Built-up areas in India run 2 to 10 degrees Celsius hotter than the rural land they replaced. UHI is now the primary driving factor of power demand. While industrial power demand has remained relatively stable in several regions, residential demand has surged sharply because cities are becoming significantly hotter. ACs, which are projected to cover up to 40 per cent of households by 2030, pump heat back onto the streets, warming cities further.
According to the 2011 Census, nearly 31 per cent of India’s population resides in urban areas, contributing 63 per cent to the country’s Gross Domestic Product (GDP). By 2030, approximately 40 per cent of the population would likely reside in urban areas and contribute 75 per cent of the GDP. According to a 2024 study by the Indian Space Research Organisation (ISRO), 32 cities show significant increases in urban temperatures and heatwaves, particularly in the Indo-Gangetic Plains, largely due to land cover changes from non-built to built-up areas.
Humidity tightens the trap. The body cools itself by evaporating sweat; when the air is already saturated, that mechanism fails. Heat index—the ‘feels-like’ temperature—can run several degrees Celsius above the thermometer reading. People do not switch on ACs because of what the thermometer says. They switch them on because of what the air does to their skin.
The night used to be the grid’s reprieve. It isn’t anymore. Concrete that has stored heat all day radiates it back through the small hours; bedrooms that once cooled by midnight now stay warm till 4 am. Cooling appliances run longer, the next day starts from a warmer baseline. According to data by the Council on Energy, Environment and Water (CEEW), night temperatures have risen by about 0.21 degrees Celsius per decade since 2010, affecting 35 states and Union Territories. Sikkim has the strongest recent nighttime warming signal. West Bengal, Andhra Pradesh, Karnataka, Goa, Uttarakhand, and Bihar also show relatively strong increases.
The severity of UHI associated with heatwaves and heat stress-related mortality is now one of the major concerns, particularly in densely populated cities. The observed UHI intensity varies across the country between 2 and 10 degrees Celsius, with northwest India seeing a more pronounced temperature gradient.
Can power supply keep up? On paper, yes. India’s installed capacity crossed 533 GW by March 2026, with non-fossil sources around 53 per cent of the total. But installed power is not the same as available. At the April 2026 peak, solar and hydro met 30 per cent of demand and coal was pushed to the edge of its technical flexibility floor of 55 per cent, with gas covering the ramping gap at high cost.
The 80 GW of solar power that cushioned the afternoon disappears at sunset, just as residential cooling load is climbing into the evening, and that load now stretches past midnight, the very hours when renewables are absent and the grid leans hardest on coal. Resource-adequacy modelling by the Central Electricity Authority (CEA) projects unserved energy by 2034 of up to 14.9 per cent in Uttar Pradesh, 11 per cent in West Bengal and 30 per cent in Assam—assuming all planned capacity is built on time. Storage at scale is the missing piece, and is years away.
Which leaves behaviour, the cheapest, fastest lever, still available. Most Indian households set their ACs at 18-21degrees Celsius, a habit, not a need. The Bureau of Energy Efficiency’s comfort range is 24-25 degrees Celsius. Raising the setting from 20 to 24 degrees Celsius cuts power use by about 24 per cent, and each 1 degree Celsius rise saves roughly 6 per cent.
If half of India’s AC users moved to 24 degrees Celsius, the country could save 10 billion units a year. Pair the AC with a ceiling fan and 28 degrees Celsius feels comfortable room temperature. Pre-cool the room before peak hours and switch off by 11 pm. Service the unit so the compressor isn’t running blind through dust. Use heavy curtains during the day so walls don’t soak in heat. The thing is, the power grid can be expanded but at a cost, whereas changing consumer behaviour brings huge savings for households as well as the nation.
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The number is only half the perspective; the real story is that this demand was not coming from added industrial production contributing to the country’s economy but from urban bedrooms.
For decades, India’s power load was shaped by factories and farm pumps. Of late, Uttar Pradesh, a state with no comparable industrial base, sits at the top of the demand table. Six of the top 10 demand-driving states on May 21—UP, Tamil Nadu, Bihar, Odisha, West Bengal and Andhra Pradesh—are not considered as industrial powerhouses. They are simply hot, humid and increasingly air-conditioned regions.
In Delhi, where AC penetration is the highest in the country, a discom official estimated that air-conditioning alone accounts for 30-50 per cent of the domestic and commercial power consumption.
Rapid urbanisation, which modifies Land Use and Land Cover (LULC), is behind the elevated temperatures in cities and towns; and this creates the phenomenon known as Urban Heat Island (UHI). This UHI effect translates into kilowatts of additional power consumed.
Here is how it happens: concrete, asphalt and glass absorb solar radiation through the day and release it long after sunset. Built-up areas in India run 2 to 10 degrees Celsius hotter than the rural land they replaced. UHI is now the primary driving factor of power demand. While industrial power demand has remained relatively stable in several regions, residential demand has surged sharply because cities are becoming significantly hotter. ACs, which are projected to cover up to 40 per cent of households by 2030, pump heat back onto the streets, warming cities further.
According to the 2011 Census, nearly 31 per cent of India’s population resides in urban areas, contributing 63 per cent to the country’s Gross Domestic Product (GDP). By 2030, approximately 40 per cent of the population would likely reside in urban areas and contribute 75 per cent of the GDP. According to a 2024 study by the Indian Space Research Organisation (ISRO), 32 cities show significant increases in urban temperatures and heatwaves, particularly in the Indo-Gangetic Plains, largely due to land cover changes from non-built to built-up areas.
Humidity tightens the trap. The body cools itself by evaporating sweat; when the air is already saturated, that mechanism fails. Heat index—the ‘feels-like’ temperature—can run several degrees Celsius above the thermometer reading. People do not switch on ACs because of what the thermometer says. They switch them on because of what the air does to their skin.
The night used to be the grid’s reprieve. It isn’t anymore. Concrete that has stored heat all day radiates it back through the small hours; bedrooms that once cooled by midnight now stay warm till 4 am. Cooling appliances run longer, the next day starts from a warmer baseline. According to data by the Council on Energy, Environment and Water (CEEW), night temperatures have risen by about 0.21 degrees Celsius per decade since 2010, affecting 35 states and Union Territories. Sikkim has the strongest recent nighttime warming signal. West Bengal, Andhra Pradesh, Karnataka, Goa, Uttarakhand, and Bihar also show relatively strong increases.
The severity of UHI associated with heatwaves and heat stress-related mortality is now one of the major concerns, particularly in densely populated cities. The observed UHI intensity varies across the country between 2 and 10 degrees Celsius, with northwest India seeing a more pronounced temperature gradient.
Can power supply keep up? On paper, yes. India’s installed capacity crossed 533 GW by March 2026, with non-fossil sources around 53 per cent of the total. But installed power is not the same as available. At the April 2026 peak, solar and hydro met 30 per cent of demand and coal was pushed to the edge of its technical flexibility floor of 55 per cent, with gas covering the ramping gap at high cost.
The 80 GW of solar power that cushioned the afternoon disappears at sunset, just as residential cooling load is climbing into the evening, and that load now stretches past midnight, the very hours when renewables are absent and the grid leans hardest on coal. Resource-adequacy modelling by the Central Electricity Authority (CEA) projects unserved energy by 2034 of up to 14.9 per cent in Uttar Pradesh, 11 per cent in West Bengal and 30 per cent in Assam—assuming all planned capacity is built on time. Storage at scale is the missing piece, and is years away.
Which leaves behaviour, the cheapest, fastest lever, still available. Most Indian households set their ACs at 18-21degrees Celsius, a habit, not a need. The Bureau of Energy Efficiency’s comfort range is 24-25 degrees Celsius. Raising the setting from 20 to 24 degrees Celsius cuts power use by about 24 per cent, and each 1 degree Celsius rise saves roughly 6 per cent.
If half of India’s AC users moved to 24 degrees Celsius, the country could save 10 billion units a year. Pair the AC with a ceiling fan and 28 degrees Celsius feels comfortable room temperature. Pre-cool the room before peak hours and switch off by 11 pm. Service the unit so the compressor isn’t running blind through dust. Use heavy curtains during the day so walls don’t soak in heat. The thing is, the power grid can be expanded but at a cost, whereas changing consumer behaviour brings huge savings for households as well as the nation.
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