Limits to supply, rising demand: Behind Keralam’s electricity crisis

Why in the News

The Keralam State Electricity Board (KSEB) has instituted power cuts lasting between 30 minutes and an hour to manage peak hour demand, including cuts at night. Average daily demand in September 2026 reached about 5,000 MW against 3,794 MW in September 2025, and only 4,200 MW has been met. The shortfall arrives at the hour when the state’s largest renewable asset stops producing, because rooftop solar output ends at dusk and the state has no storage in service. The tension is that a state that leads the country in rooftop solar cannot use any of it against the demand peak that is actually breaking its system.

How does a State draw power from the Central pool?

1. What a Central Generating Station is: Central Generating Stations (CGS) are large power generating stations owned centrally rather than by a state utility.
2. How allocation works: The Union Ministry of Power periodically allocates generation capacity to states from its pool of unallocated quota in those stations.
3. Who has jurisdiction over electricity: Electricity is a subject on the Concurrent List of the Constitution, so both the Centre and the states have jurisdiction over it.

How large is the shortfall?

1. Demand has risen sharply in a year: Average daily demand in September 2026 was about 5,000 MW, against 3,794 MW in September 2025.
2. Supply has not kept pace: The state has met only 4,200 MW, leaving a daily shortage.
3. Own generation and the Central pool draw: Keralam produces only 1,650 MW and draws 1,500 MW from the Central pool.
4. The structural position: The state generates only 25 per cent of its actual requirement from all sources including hydel, solar and wind, against 86 per cent for Andhra Pradesh and 50 per cent for Tamil Nadu.

Why has hydropower been throttled?

1. The monsoon failed: The southwest monsoon was weak through the June to September period, with Keralam recording a 26 per cent deficit in seasonal rainfall till 11 September.
2. The El Nino effect: The El Nino effect, meaning the abnormal warming of surface waters in the equatorial Pacific Ocean that can suppress the Indian monsoon, has been witnessed this year.
3. Reservoir water storage: Water storage across all KSEB reservoirs stood at only 63.75 per cent of the maximum storage level as of 10 September.
4. The Board is rationing water, not power alone: KSEB has throttled down hydropower generation deliberately, holding storage against the withdrawal of the monsoon and higher temperatures in the weeks ahead.

Why does rooftop solar not close the night gap?

1. The state leads on rooftop capacity: Keralam’s solar production hit 2,508 MW by the end of May, with the vast majority of it rooftop panels.
2. The scheme behind the build: Under PM Surya Ghar, Keralam has 2.96 lakh installations covering 3,03,531 households.
3. The output arrives at the wrong hour: Solar power does not help meet the nighttime demand, because the state has no options to store it.
4. The storage is contracted but not running: KSEB has lined up a slew of Battery Energy Storage Systems (BESS) that are yet to become operational.

What is a Battery Energy Storage System?

1. The battery and its grid electronics: A bank of rechargeable cells with power electronics attached to the grid. It charges when generation exceeds demand and discharges when demand exceeds generation, so energy produced in one hour is delivered in another.
2. Time shifting of solar output: Solar output peaks near midday and ends at dusk, while the demand peak sits in the evening. A battery moves the midday surplus into the evening block, which is the only route by which a daytime resource serves a night peak.
3. Ramping, not only energy: A battery responds within seconds, so it also covers the sunset ramp, the period when solar falls away faster than thermal or hydro plants can raise their output.
4. The limits of stored duration: A battery holds a fixed quantity of energy and delivers it for a defined duration, commonly a few hours. It shifts a peak rather than adding generating capacity, and it supplies nothing that was not generated and stored first.

Why is night demand rising?

1. The consumer mix loads the evening: Domestic consumers make up 75 per cent of the state’s power connections, so demand rises at night rather than during working hours.
2. Temperatures are abnormally high: The state disaster management authority has put Keralam on alert for an unusual rise in temperature, with a departure of up to 4 degrees Celsius from normal.
3. Cooling load runs longer: Rising night temperatures are driving long duration air conditioner usage.
4. Electric vehicle charging: KSEB has found that nighttime demand is also rising owing to the charging of electric vehicles.

Challenges to Keralam’s power supply security

1. Buying from the exchange fails when the scarcity is national: A deficit state can outbid others only when surplus exists somewhere, and this September the shortage is countrywide. Eg. India is witnessing an unusual surge in electricity demand this September, with peak power demand nearing the level recorded during peak summer, driven by a poor monsoon and low coal stock at power plants.
   The Fix: Contract firm capacity ahead of the season under medium term agreements, so the state is not bidding into a national spot market at the moment of scarcity.
2. The coal fleet has no headroom to absorb the gap: Thermal plants are the swing capacity a deficit state usually leans on, and they are already running close to their limits. Eg. The plant load factor of most imported coal based plants is around 70 per cent or above, leaving no thermal plant that can be asked to raise generation.
   The Fix: Shift a defined share of the evening block onto demand response contracts with large consumers, so the peak is reduced rather than sourced.
3. Nothing firm replaces solar at the evening ramp: The system loses its entire solar output within an hour of sunset, which is also the hour demand rises, and only fast ramping capacity can bridge that. Eg. Nationally, generation from gas based plants rose 80.3 per cent during 1 to 9 September over the same period last year, with the Centre relying on 4.5 to 5.5 GW of gas based capacity to meet the evening shortfall.
   The Fix: Bring the Board’s contracted battery systems into service against a dated commissioning schedule, since they are the only asset that can move midday solar into the evening block.
4. Distributed solar weakens the utility that must still serve the peak: A rooftop consumer exports at midday and draws at night, so the utility recovers less revenue while carrying the same obligation to supply at the peak. Eg. Keralam’s rooftop capacity is concentrated in domestic connections, which are the same consumers driving the night peak.
   The Fix: Move rooftop settlement from net metering to net billing with a time of day price, so midday export and evening drawal are valued at what each is actually worth to the system.

Conclusion

The immediate crisis will ease when the monsoon withdrawal passes and temperatures fall, and the Board’s rationing is calibrated to hold storage until then. What will not change on its own is the structural position, because a state generating a quarter of its own requirement is buying the rest in a market that tightens in exactly the months it needs power most. The measurable marker is the commissioning of the contracted battery systems, since until they run, every additional megawatt of rooftop solar adds to the state’s daytime surplus and nothing to its evening deficit.

Back2Basics: PM Surya Ghar Muft Bijli Yojana

1. PM Surya Ghar: Muft Bijli Yojana: A central scheme under the Ministry of New and Renewable Energy to install rooftop solar systems on residential buildings.
2. Coverage target: One crore households, with free electricity of up to 300 units a month for the households that install under it.
3. Household financing route: Central financial assistance is credited directly to the beneficiary’s bank account, alongside access to collateral free low interest loans for the balance cost.
4. Capacity building component: The scheme carries a capacity building component covering training in installation, operation, maintenance and repair of rooftop systems at the local level.

Matching Previous Year Question

“[2025] Consider the following statements about ‘PM Surya Ghar Muft Bijli Yojana’: I. It targets installation of one crore solar rooftop panels in the residential sector. II. The Ministry of New and Renewable Energy aims to impart training on installation, operation, maintenance and repairs of solar rooftop systems at grassroot levels. III. It aims to create more than three lakhs skilled manpower through fresh skilling and up-skilling, under scheme component of capacity building. Which of the statements given above are correct? (a) I and II only (b) I and III only (c) II and III only (d) I, II and III ANSWER: (d)”