18 June 2026
Hindustan Times
Op-eds
After dark, India’s power systems are facing their hardest test. By the
time the evening news begins, the heat in Indian cities has still not eased.
Apartments, offices, and shop floors, continue to hold the day’s temperature,
keeping cooling demand elevated well after sunset. This is reshaping the
operating logic for our power infrastructure.
Across
much of India, very warm nights are rising faster than very hot days,
especially in dense urban districts where built surfaces trap heat through the
day and release it after dark. In Delhi, the summer of 2026 brought 45°C-plus
daytime heat and May nights that ranked among the city’s warmest in more than a
decade.
That extends the stress window beyond the afternoon peak into hours when networks, transformers and dispatch decisions are already under pressure. The next test of summer reliability will come after sunset.
Delhi
is the sharpest illustration of a national pattern. Extreme heat has spread
across the same districts that carry a large share of India’s population,
economic activity, and infrastructure demand. About 76% of the population,
already fall in high to very high heat-risk categories. In 2024, heat exposure
stripped 247 billion potential labour hours from the economy. The income loss:
$ 194 billion.
These
losses have found their way into productivity statistics. They arrive at the
power system through longer cooling cycles, higher local demand, and sustained
pressure on the distribution layer. India’s 2.5GW night time shortfall in May
2026, enough to power almost two million households, came to a total demand of
251GW. Reports of overload and fault-driven outages in Noida, Ghaziabad,
Mohali, and Mumbai point to this reality.
The
central challenge in summer power is the evening load shape, a dual peak, with
demand rising around solar hours and remaining elevated again between 9 PM and
11 PM. Last May, demand reached ~230 GW at 3 PM and still held at ~227 GW later
in the evening. Solar can manage the day; after sunset, the burden falls
entirely on storage, hydro, wind and thermal generation.
That is the gap India’s clean energy strategy needs to close. The opportunity lies in extending clean power’s reach into the evening through storage, hybrids, stronger transmission, and flexible hydro and wind, and in timing. Time-of-day tariffs already incentivise shifting demand into solar hours. Pre-cooling, demand response, and efficient cooling can move load into cleaner windows, shrinking the fossil-heavy tail.
A flatter peak and stronger evening supply give storage and hybrids more room, reduce coal-heavy balancing, and make the clean transition more resilient.
Buildings
are the hidden variable in India’s evening grid stress. In dense urban
districts, roofs, walls, pavements, and neighbourhood layouts absorb heat
through the day and release it slowly after sunset, turning every city block
into a slow-burning load on the distribution network.
Cooler
roofs, reflective materials, shading, and better ventilation lower indoor heat
and reduce the electricity required to maintain habitable spaces during the
hottest hours. The evidence is already there: cool-roof interventions in
Chennai’s Perumbakkam reduced roof surface temperatures by 9–12°C, lowered
indoor temperatures by 0.5–1.5°C, and delivered electricity savings of up to
12%.
India
already has the pieces—IMD district-level warnings, grid operators tracking
demand and reserves, DISCOMs managing local network stress. The opportunity is
to run them as one system: A shared framework that connects forecast signals, clean
energy dispatch, building performance and community response into a single
picture of where the night will be hardest. Three bold shifts make would make
this real.
· Seeing
your risk earlier: Right now, stress becomes visible only when it arrives in
the form of an overloaded feeder, a tripped transformer, an outage call.
Integrating forecast signals with operational data creates a live picture of
which districts, feeders and transformers are most likely to converge into
crisis during the 9 PM–11 pm window, giving grid operators, and municipal
authorities time to act before the system speaks for itself.
· Anchoring
the night with clean power: The evening window is where clean energy’s reach is
still incomplete. A shared operational picture means storage, flexible hydro
and wind can be dispatched precisely into the hours of highest pressure. This
is where the clean transition becomes an operational discipline, not just an
infrastructure target.
· Closing the loop on demand: Supply is only half the equation. Cooler roofs, better-ventilated buildings and shaded urban infrastructure reduce what the grid has to carry before the evening even begins. Paired with cooling shelters, water access and hospital preparedness in the most exposed neighbourhoods, the operating system reaches all the way to the people at the end of the line, reducing the load and protecting those who feel it most when it fails.
As
nights grow hotter and summers run longer, the measure of infrastructure will
have to shift with them. Cities and states that strengthen grids, reduce heat
in buildings, and carry cleaner power deeper into the evening will be better
prepared for the climate already here.
India’s
power system has learnt to survive the day. It now needs to learn to survive
the night, when demand remains high, resilience is tested in real time, and the
heat of the day is still lingering in the city. That is the next infrastructure
advantage: systems that keep performing after dark.
(The
views expressed are personal)
This
article is authored by Vaishali Nigam Sinha, co-founder, ReNew.
