New Delhi: Soaring electricity demand and lower output from hydropower plants hit by weak rainfall have delayed annual repair and maintenance work on thermal power plants during the monsoon season, exposing the coal-fired generation units to the risk of breakdown.
State governments have asked utilities such as state-owned NTPC Ltd, India’s biggest power generator, to keep their plants running, said several people aware of the development.
Repair and maintenance work on thermal power units with combined capacity of producing 13,000MW to 20,000MW has been deferred against the backdrop of the massive power transmission failures on 30-31 July that left around 700 million people without electricity for many hours. The delay could impair plant efficiencies and result in power outages.
“There is a risk. While annual repair and maintenance of thermal power plants are carried out during the window provided by the monsoons, this year it has not been the case,” said a former official at the Central Electricity Authority (CEA), India’s apex power sector planning body, who spoke on condition of anonymity.
Pushed to limit: NTPC’s Dadri plant in Uttar Pradesh.
NTPC chairman and managing director Arup Roy Choudhury sought to downplay the issue and said that the company would meet the technical requirements regarding maintenance and added that, anyway, the annual shutdown for maintenance, would have affected less than 2% of the company’s power generation capacity. “It is no issue.”
The former CEA official disagrees.
“While it takes around 20 days for a regular annual maintenance, a capital maintenance as prescribed by the original equipment manufacturer such as Bhel (Bharat Heavy Electricals Ltd) has to be carried out once in every five years and requires around 45 days. Not carrying out both these types of maintenance work poses huge risk for the equipment.”
India has 217 thermal plants. The country also has 176 hydropower projects and six nuclear plants.
“There is no distinction between annual and capital maintenance as we bunch them together to reduce our generation losses,” said a senior executive at NTPC who spoke on condition of anonymity. “While the maintenance planned in April, May and June went as per schedule, in July the states requested for deferment of maintenance work due to a weak monsoon. As of now, there is no clarity on August maintenance work. Any deferment leads to higher damage, secondary damage, longer outage of unit and statutory violations.”
The NTPC units on which maintenance work has been put off include Talcher in Orissa and Ramagundam in Andhra Pradesh. NTPC generates about 39,174MW of electricity through its own projects and joint ventures.
A second senior executive at NTPC, who also didn’t want to be identified, said: “The risk of a breakdown is always there if repair and maintenance doesn’t take place. In any given year some units at a project will have to go for capital maintenance. The statutory bare minimum will be met. We will see when to make our units undergo maintenance work and that will depend upon demand-supply situation and hydropower generation capacity.”
“The annual maintenance of power plants involves various activities—proper checks, supervision, cleaning, tightening, necessary repair of the plant equipment (electrical, mechanical) and accessories,” said Amol Kotwal, deputy director of the energy and power systems practice for South Asia and West Asia at Frost and Sullivan, a consulting firm.
“Annual maintenance on timely basis is extremely important to ensure the equipment life and smooth running of the plants. A delay could potentially impact proper power plant running and could lead to a breakdown, besides affecting the equipment life and overall operations,” Kotwal said.
A.S. Bakshi, chairman of CEA, didn’t respond to repeated phone calls or to a message left on his cellphone on Friday.
“The units have been asked to defer maintenance,since there was lower hydro power production due to lack of rains,” said a power ministry official who did not wish to be identified. “However, this maintenance can’t be deferred indefinitely as the machines need to be shut down for maintenance. We are doing it in such a way that neither the power situation in the country suffers nor these machines risk breakdown. This maintenance will be taken up once the hydro power situation in the country improves. The units have been asked to defer maintenance by a month.”
India has an installed power generation capacity of 205,340MW, of which around 135,236.43 MW is thermal-based and 39,291.4MW is hydro-based. The country’s power demand during peak consumption hours—between 8am and 11am and 5pm and 8pm—is 124,995MW.
Hydropower generation in April and June fell 8.8% from last year, showed a research report from Barclays Capital that used data from the CEA.
The deficient monsoon rainfall has hurt hydropower generation significantly, putting more pressure on thermal power generators as demand for electricity rises from consumers for cooling needs and farmers for irrigation using electric pumps.
This is not the first time repair and maintenance work has been delayed. The Union government had directed utilities such as NTPC not to shut thermal power plants for repair and maintenance in 2008, when, too, hydropower generation fell short of expectations.
The June-September monsoon accounts for nearly 80% of the country’s annual rainfall and is vital for the economy, being the main source of water for agriculture and hydropower generation.
During the monsoon, when there’s a rise in hydroelectric generation, thermal generation units are usually shut for maintenance. With hydroelectric generation remaining stagnant because of the poor rainfall, there is no other cushion to meet the growing demand for power.