Summer arrived with full force in Tamil Nadu this April, leading to an immediate increase in power demand. Maximum demand reached 21,307 megawatts (MW) on 29 April. On the same day, the state witnessed a maximum power consumption of 471.45 million units (MU). This year, demand has regularly crossed 21,000 MW due to heat. Last year, the high demand was less than the 2024 requirement. The maximum demand recorded in 2024 was 20,830 MW on 2 May, and the highest consumption recorded was 454.32 MU on 30 April.
However, there have been no major power cuts this year, as happens when demand increases. However, there are complaints of low voltage and supply disruption in many areas of Chennai. The capital consumes about 5,000 MW, and the maximum demand reached 4,769 MW on May 31, 2024.
Network upgraded
Over the past few years, electricity managers have initiated projects to upgrade the transmission network. However, he says that despite the upgrades, disruptions occur due to punctures in the underground cable network or disruptions in overhead cables.
A senior official of Tamil Nadu Power Distribution Corporation Limited (TNPDCL) says that due to the heat this year, the demand for electricity in all the districts has crossed the previous maximum limit. But the power department anticipated the demand and prepared well: the state’s installed capacity is about 40,000 MW, including 17,000 MW of thermal power and 13,000 MW of wind and solar power.
In Chennai, people in the western suburbs of Avadi, Pattabhiram, Thandurai and Thiruninravur have been regularly affected by low voltage and disruptions. Residential areas in Avadi, which was upgraded as a municipal corporation, have grown in recent times. A proposal was made to underground the overhead cables for residents of Tamil Nadu Housing Board (TNHB) flats. But the work has not been started. Consumer activist T. Sadagopan says it has been more than five years since the work of upgrading the 110 KV substation to 230 KV in Avadi began. But the project is progressing at a slow pace, resulting in supply disruptions in nearby Pattabhiram and Thandurai. He points out that although the 110 KV substation at Pattabhiram was opened in 2007, the improvement work has not been done regularly. A massive fire broke out in the substation, causing supply disruption in Pattabhiram for more than 48 hours.
S Dharanidharan, a resident of TNHB area in Avadi, says Tidal Park in Avadi does not have the dedicated substation required to power the 21 floors. The Avadi-Poonamallee corridor has many multi-storey apartments and gated communities. But as promised, the gated communities do not yet have substations and transformers.
TNPDCL officials say they have planned well by purchasing 1,500 MW of medium term power to meet the peak demand and avoid buying expensive power from the exchange. The share of medium term power in the total available energy of 25,000 MW is 2,300 MW.
“Every year we expect a 5% to 6% growth in demand; but this year it has gone up by more than 7%,” says a senior TNPDCL official. The Central Energy Authority in its report has estimated that the state will reach a peak demand of 21,959 MW. In anticipation, TNPDCL set up substations in the city and outskirts and replaced conventional transformers with 5,500 ring main units (RMUs).
substation installed
The Energy Department has set up substations and upgraded existing substations from Virudhunagar to North Chennai and Coimbatore to supply electricity across the state. The 765-kV network will help reduce transmission losses, carry large amounts of power and ensure reliable supply. Augmentation work has been carried out on seven of the 400-kV substations, 11 of the 230-kV substations and 60 of the 110-kV substations.
In the Coimbatore region, which includes Coimbatore, Tiruppur and Nilgiris districts, demand has reached an all-time high of 3,109 MW this year. Summer demand is usually less than 2,700 MW. But this year it has gradually increased from 2,900 MW to 3,100 MW every month. Average daily consumption also reached 59.63 MU as against 57.39 MU in March. A substantial number of wind and solar power plants in the highly industrialized Tiruppur and Coimbatore districts have helped in providing steady and stable supply to the city.
Coming in handy: Solar panels are being installed on the roof of Dr. MGR Central Railway Station and Suburban Railway Station in Chennai in 2019. Solar power helps handle day time consumption. | Photo courtesy: B. Jyoti Ramalingam
In Erode, the average demand this summer reached 1,000 MW per day. The daily demand during summer at Erode and Gobchettipalayam averages 800 MW. TNPDCL officials say solar power generation supports day time consumption, while the surge in night time demand is being met with adequate supply.
Namakkal residents are unhappy with the delay in the completion of the 20-MW Kolli Hills Hydro Electric Project, estimated to cost ₹338.79 crore. Its foundation was laid in December 2018. Its commissioning was scheduled for April 2021. The work was halted due to the COVID-19 lockdown and after that it slowed down again. The project is still under implementation.
Solar power has come as a big relief to the electricity department to manage the peak hour demand in the Tiruchi region, which includes Tiruchi, Dindigul, Perambalur, Ariyalur and Pudukkottai districts. The region recorded the highest demand of 1,760 MW in the first week of May. Demand in April and May will generally be around 1,500 MW-1600 MW.
According to official sources, there is no power cut in the area during peak demand season, except during times of heavy rain. Private solar power units in various parts of the region have helped power managers meet demand during peak hours. “We have an installed capacity of 661 MW of solar power by private companies. The bright sunshine helped them utilize the infrastructure to maximize production. This has helped us manage the daytime power demand,” says a senior TNPDC official in Tiruchi.
rain to the rescue
Even though power managers are confident about managing demand in the delta districts, sudden rains have helped reduce demand. The official says that with the arrival of the south-west monsoon the demand will gradually reduce.
TNPDCL officials also hope that wind power generation, which has remained stable so far in May, from an installed capacity of over 9,000 MW, will increase in the coming months. In Tirunelveli and Tenkasi districts, where there are more than 15 lakh electricity connections, the demand has reached 500 MW this summer. The saving grace is the supply from coal-based thermal power plants in neighboring Thoothukudi. There is sufficient stock of coal in these plants. Hence there is no hindrance in generation. A senior official of TNPDCL in Tirunelveli says wind power generators in the southern part of Tirunelveli district will start production from the end of May with the onset of south-west monsoon in Kanniyakumari district and neighboring Kerala.
lack of components
However, officials are concerned about the shortage of components, including electric poles and transformers, as well as the large number of vacancies for maintenance workers. A senior official of Tirunelveli circle says more than 70% of the posts of wiremen and helpers are vacant in Tirunelveli and Tenkasi districts. But the department is handling the situation with the available manpower and contract workers. However, any delay in filling these vacancies could lead to problems in resolving power disruptions, in addition to revenue loss.
Kanniyakumari residents want the pumped storage project at Velimalai to be expedited. The government announced the project in the 2025 budget. As of now, only the tender has been issued for selection of developer for the 1,000-MW/6,000-MW Velimalai Pumped Storage Hydro-Electric Project.
net loss
According to power managers, the total loss of the power department has crossed the ₹1 lakh crore mark due to the 200 units of free power announced by the new government and the burden will get worse. With the new scheme, the annual tariff subsidy for domestic consumers alone is estimated to exceed ₹10,100 crore this financial year.
The state is known for its impressive performance in human development indicators. But due to poor financial management, the condition of the energy sector remains poor. As a result, the power sector has become dependent on grants and subsidies for generation and transmission projects.
According to the energy department’s demand for 2025-26 tabled in the Assembly, tariff subsidies and grants had crossed the ₹30,000 crore mark for 2024-25 and now stand at ₹31,849 crore. Subsidies and grants have tripled to ₹10,834 crore for 2016–17.
revenue determination
Navneeraj Sharma, an independent consultant, says Tamil Nadu has the potential to become an “electro-state” by combining real industrial depth with some of the strongest renewable energy endowments in the country. But its power sector is in urgent need of revenue generation.
Mr Sharma says the problem for TNPDCL is not in providing free power, but in poor demand forecasting, power purchase planning and designing tariffs. Errors in load forecasting force discoms to buy short-term power at higher prices, leading to operating losses and increased dependence on government funding. He says much of the domestic tariff structure benefits middle-class and upper-middle-class families, not those who actually need support. This makes it difficult to justify the fiscal burden. He says as Tamil Nadu’s renewable energy share grows, accurate consumer-level data – especially for agriculture – will be essential for reliable long-term planning.
Power managers say that when the government allows big industries to set up captive power units, the grid condition worsens. Large industrial units avoid paying high industrial tariffs by setting up their own captive units, thereby forcing smaller units to pay higher tariffs. Daytime pricing that rewards load-shifting in the solar-rich afternoon will give the industry a reason to stay on the grid rather than leave it.
(M. Soundarya Preetha in Coimbatore, SP Saravanan in Erode, Rohan Premkumar in Udhagamandalam, M. Sabari in Namakkal, C. Jayasankar in Tiruchi, P. Sudhakar in Tirunelveli, and B. in Kanniyakumari. With inputs from Shankari Nivethitha.)
